back to indexAlien Debate: Sara Walker and Lee Cronin | Lex Fridman Podcast #279
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I don't know what it's like to be an alien.
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I would like to know.
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Two alien civilizations coexisting on a planet,
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what's that look like exactly?
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When you see them and they see you,
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you're assuming they have vision,
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they have the ability to construct in 3D and in time.
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That's a lot of assumptions they're making.
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What human level intelligence has done is quite different.
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It's not just that we remember states
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that the universe has existed in before,
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it's that we can imagine ones that have never existed
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and we can actually make them come into existence.
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So you can travel back in time sometimes.
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You travel forward in time to travel back.
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The following is a conversation
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with Sarah Walker and Lee Cronin.
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They have each been on this podcast once before
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individually and now for their second time,
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they're here together.
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Sarah is an astrobiologist and theoretical physicist.
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Lee is a chemist and if I may say so,
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the real life manifestation of Rick from Rick and Morty.
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They both are interested in how life originates
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and develops both life here on earth and alien life,
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including intelligent alien civilizations
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out there in the cosmos.
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They are colleagues and friends
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who love to explore, disagree and debate
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nuanced points about alien life.
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And so we're calling this an alien debate.
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Very few questions to me are as fascinating
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as what do aliens look like?
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How do we recognize them?
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How do we talk to them?
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And how do we make sense of life here on earth
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in the context of all possible life forms
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that are out there?
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Treating these questions with the seriousness
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and rigor they deserve is what I hope to do
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with this conversation and future ones like it.
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Our world is shrouded in mystery.
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We must first be humble to acknowledge this
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and then be bold and diving in
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and trying to figure things out anyway.
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This is the Lex Friedman podcast.
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To support it, please check out our sponsors
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in the description.
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And now, dear friends, here's Sarah Walker and Lee Cronin.
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First of all, welcome back Sarah, welcome back Lee.
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You guys, I'm a huge fan of yours.
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You're incredible people.
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I should say thank you to Sarah
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for wearing really awesome boots.
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We'll probably overlay a picture later on,
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but why the hell didn't you dress up, Lee?
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No, I'm just kidding.
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This is me dressed up.
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You were saying that you're pink,
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that your thing is pink.
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My thing is black and white, the simplicity of it.
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When did the pink, when did it hit you
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that pink is your color?
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I became pink about, I don't know, actually, maybe 2017.
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Did you know me when you first?
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I think I met you pre pink.
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Yeah, yeah, so about 2017, I think.
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I just decided I was boring
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and I needed to make a statement
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and red was too bright, so I went pink, salmon pink.
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Well, I think you were always pink.
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You just found yourself in 2017.
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There's an amazing photo of him
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where there's like everybody in their black gown
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and he's just wearing the pink pants.
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Oh, that was at the Waggonen University.
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It's totally nuts.
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100 year anniversary, they got me to give the plenary
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and they didn't find that outfit for me,
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so they were all wearing these silly hats and these gowns
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and there was me dressed up in pink
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looking like a complete idiot.
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We're definitely gonna have to find that picture
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and overlay it, big full screen, slow motion.
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All right, let's talk about aliens.
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We'll find places we disagree and places we agree,
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life, intelligence, consciousness, universe, all of that.
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Let's start with a tweet from Neil deGrasse Tyson
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stating his skepticism about aliens wanting to visit Earth.
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Quote, how egocentric of us to think that space aliens
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who have mastered interstellar travel across the galaxy
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would give, pardon the French,
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would give a shit about humans on Earth.
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So let me ask you, would aliens care about visiting Earth,
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observing, communicating with humans?
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Let's take a perspective of aliens, maybe Sarah first.
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Are we interesting in the whole spectrum
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of life in the universe?
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I'm completely biased, at least as far as I think right now
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we're the most interesting thing in the universe.
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So I would expect based on the intrinsic curiosity
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that we have and how much I think that's deeply related
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to the physics of what we are,
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that other intelligent aliens would want to seek out
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examples of the phenomena they are
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to understand themselves better.
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And I think that's kind of a natural thing to want to do.
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And I don't think there's any kind of judgment
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on it being a lesser being or not.
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It's like saying you have nothing to learn
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by talking to a baby.
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You have lots to learn, probably more than you do
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talking to somebody that's 90.
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So yeah, so I think they absolutely would.
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So whatever the phenomena is that is human,
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there will be an inkling of the same kind of phenomena
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within alien species and they will be seeking that same.
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I think there's gotta be some features of us
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that are universal.
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And I think the ones that are most interesting,
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and I hope I live in an interesting universe,
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are the ones that are driven by our curiosity
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and the fact that our intelligence allows us to do things
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that the universe wouldn't be able to do
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without things like us existing.
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We're gonna define a lot of terms.
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One of them is interesting.
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That's a very interesting term to try to define.
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Ali, what do you think?
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Are humans interesting for aliens?
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Well, let's take it from our perspective.
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We want to go find aliens as a species quite desperately.
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So if we put the shoe on the other foot,
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of course we're interesting.
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But I'm wondering and assuming
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that we're at the right technological capabilities
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to go searching for aliens, then that's interesting.
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So what I mean is,
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if there needs to be a massive leap in technology
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that we don't have,
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how will aliens prioritize coming to Earth and other places?
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But I do think that they would come and find us
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because they'd want to find out about our culture,
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what things are universal.
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I mean, I'm a chemist.
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I would say, well, is the chemistry universal, right?
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Are the creatures that we're going to find
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making all this commotion,
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are they made of the same stuff?
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What does their science look like?
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Are they off planet yet?
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I guess there's, so I think that Neil deGrasse Tyson
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is being slightly pessimistic
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and maybe trying to play the tune
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that the universe is vast
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and it's not worth them coming here.
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I don't think that,
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but I just worry that maybe we don't have
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the ability to talk to them.
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We don't have the universal translator.
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We don't have the right physics,
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but sure, they should come.
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We are interesting.
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I want to know if they exist.
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It would make it easier if they just came.
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So again, I'm going to use your tweets
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like it's Shakespeare and analyze it.
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thinking about aliens, thinking about aliens.
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So how much do you think aliens
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are thinking about other aliens, including humans?
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So you said, we humans want to visit.
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Like we're longing to connect with aliens.
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Can you introspect that?
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Is that an obvious thing that we should be,
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like what are we hoping to understand
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by meeting aliens exactly?
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Asking as an introvert, it's like,
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I ask myself this all the time.
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Why go out on a Friday night to meet people?
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What are you hoping to find?
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I think the curiosity, so when I saw Sarah put that tweet,
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I think I answered it actually as well,
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which was we are thinking about trying to make contact.
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So they almost certainly are,
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but maybe there's a number of classes.
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There are those aliens that have not yet made contact
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with other aliens like us.
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Those aliens have made contact with just one other alien
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and maybe it's an anticlimax and slime, right?
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And aliens have made contact
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with not just one set of intelligent species, but several.
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That must be amazing actually.
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Literally there are some place in the universe,
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there must be one alien civilization.
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Let's not make contact with not one,
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but two other intelligent civilizations.
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So they must be thinking about it.
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There must be entire degree courses on aliens,
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thinking about aliens and universal cultural norms.
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Do you think they will survive the meeting?
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And by the way, Lee did respond saying,
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that's all the universe wants.
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So Sarah said, thinking about aliens, thinking about aliens.
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Lee said, that's all the universe wants.
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And then Sarah responded, cheeky universe we live in.
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So cheeky is a cheeky version of the word interesting,
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all of which we'll try to define mathematically.
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Cheeky might be harder than interesting.
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Because there's humor in that too.
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I think there's a mathematical definition of humor,
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but we'll talk about that in a bit.
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Yeah, sure there is, yeah.
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So if you're a graduate student alien
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looking at multiple alien civilizations,
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do you think they survive the encounters?
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I think there's a tendency to anthropomorphize
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a lot of the discussions about alien life,
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which is a really big challenge.
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So usually when I'm trying to think about these problems,
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I don't try to think about us as humans,
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but us as an example of phenomenon
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that exists in the universe that we have yet to explain.
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And it doesn't seem to be the case
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that if I think about the features,
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I would argue are most universal about that phenomenon,
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that there's any reason to think
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that a first encounter with another lineage
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or example of life would be antagonistic.
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And I think there's this kind of assumption,
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I mean, going back to Neil deGrasse Tyson's quote,
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I mean, it kind of bothers me because there's a,
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I mean, I'm a physicist,
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so I know we have a lot of egos
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about how much we can describe the world,
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but that there's this like,
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because we understand fundamental physics so well,
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we understand alien life and we can kind of extrapolate,
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and I just think that we don't.
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And the quest there is really, you know,
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really to understand something totally new
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about the universe, and that thing just happens to be us.
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There's something else more profound.
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I think Neil was just being, again,
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he's just trying to stir the pot.
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I would say from a contingency point of view,
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I want to know how many ways
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does the universe build structures, build memories, right?
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And then I want to know if those memories
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can interact with each other.
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And if you have two different origins of life
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and then origins of intelligence,
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and then these things become conscious,
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surely you want to go and talk to them
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and figure out what commonalities you share.
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And it might be that we're just unable to conceive
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of what they're going to look like.
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They're just going to be completely different,
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you know, infrastructure,
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but surely we'll want to go and find out a map.
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And surely curiosity is a property
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that evolution has made on earth.
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And I can't see any reason
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that it won't happen elsewhere
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because curiosity probably exists
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because we want to find innovations in the environment.
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We want to use that information to help our technology.
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And also curiosity is like planning for the future.
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Are they going to fight us?
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Are we going to be able to trade with them?
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So I think that Neil's just, I don't know,
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maybe, you know, I mean, give a shit.
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That's really, I think that's really down on earth, right?
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How would aliens categorize humans, do you think?
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So let's put it the other way around.
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Maybe, no, no, no.
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Maybe we could, the thing is a bit odd, right?
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Look at Instagram, Twitter,
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all these people taking selfies.
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I mean, does the universe
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is the ultimate state of consciousness,
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thinking beings that take photographs themselves
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and upload them to an internet
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with other thinking beings looking at each other's photos.
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So I think that they will be.
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What's wrong with that?
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I did not say there was anything wrong with it.
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It's consciousness manifested at scale.
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Selfies, Instagram.
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It's like the mirror test at scale.
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Yeah, I do think that curiosity
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is really the driving force
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for why we have our technology, right?
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If we weren't curious, we wouldn't go out, left the cave.
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so I think that Neil's got it completely wrong, in fact.
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Actually, of course they'd want to come here.
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It doesn't mean they are coming here.
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We've seen evidence for that.
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I guess we can argue about that, right?
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But I think that we want,
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I desperately, and I know that Sarah does too,
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but I won't speak for you, you're here.
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I desperately want to have missions
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to look for life in the solar system right now.
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I want to map life over the solar system.
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And then I want to understand how we can go
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and find life as quickly as possible at the nearest stars,
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and also at the same time do it in the lab,
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just to compensate, you know?
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Yeah, just one more point on this.
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If you think about sort of what's driven
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the most features of our own evolution as a species,
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and try to map that to alien species,
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I always think like optimism is what's gonna get us furthest.
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And so I think a lot of people always think
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that it's like war and conflict is gonna be the way
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that alien species will expand out into the cosmos.
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But if you just look at how we're doing it
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and how we talk about it,
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so is our future in space is always, you know,
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built from narratives of optimism.
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And so it seems to me that if intelligence does get out
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in the universe, that it's gonna be more optimism
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and curiosity driving it than war and conflict,
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because those things end up crushing you.
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So there might be some selective filter.
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Of course, this is me being an optimist.
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I'm a half full kind of person, but.
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Is it obvious that curiosity, not obvious,
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but what do you think?
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Is curiosity a more powerful force in the universe
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than violence and the will to power?
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So, because you said you framed curiosity as a way
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to also plan on how to avoid violence,
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which is an interesting framing of curiosity.
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But I could also argue that violence
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is a pretty productive way to operate in the world,
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which is like, that's one way to protect yourself.
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The best defense is offense.
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I'm not qualified to answer this, but I'll have a go.
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I think violence, let's not talk about violence.
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That's the summary of this podcast.
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I would, yeah, maybe, I would, let's not call it violence,
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but I call it erasure.
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So if you think about the way evolution works,
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or the way, obviously talk about assembly theory,
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So if you say you build,
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curiosity allows you to open up avenues, new graphs, right?
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So new features you can play.
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The ability to erase those things allows you to start again
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and do some pruning.
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So the universe, I think curiosity gets you furthest.
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Curiosity gets you rockets that land.
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It gets you robots that can make drugs.
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It gets you poetry and art and communication.
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And then, I often think wouldn't it be great in bureaucracy
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to have another world war, not literally a world war now,
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please no world war, but the equivalent
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so we get remove all the admin bureaucracy, right?
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All the admin violence, get rid of it and start again.
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Do you know what I mean?
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Because you get layers and you get redundant systems built.
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So actually a reset, let's not call it violence,
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a reset in some aspects of our culture
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and our technology allows us to then build
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more important things about the,
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because how many cookies do I have to click on?
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How many extra clicks do I have in the future of my life
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that I could remove and a bit of a reset
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would allow us to start again.
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And maybe that's how I suppose our encounter aliens will be.
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Maybe they will fight with us and say,
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oh, we're not as excited by you as we thought.
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We'll just get rid of you.
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So they might want to reset Earth.
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To be like, let's see how the evolution runs again.
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This seems like they've, there's nothing new happening here.
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They're observing for a while.
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This is just not, let's keep it more fun.
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Let's start with the fish again.
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I like how you equated violence to resetting your cookies.
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I suppose that's the kind of violence.
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In this modern world where words are violence,
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resetting cookies is the kind of violence.
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I don't know where that came from.
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I'm completely, yeah.
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That's poetic, really.
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Okay, so let's talk about life.
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What is the line between life and non life?
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And maybe at any point,
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we can pull in ideas of assembly theory.
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Like how do we start to try to define life?
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And for people listening,
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so Sarah identifies as a physicist
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and Lee identifies as a chemist.
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Of course, they are very interdisciplinary in nature
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in general, but so what is life?
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I love asking that question
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because it's so absurdly big.
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I know, I love it.
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It's my absolute favorite question in the whole universe.
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So I think I have three ways of describing it right now.
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And I like to say all three of them
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because people latch onto different facets of them.
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And so the whole idea of what Lee and I are trying to work on
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is not to try to define life,
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but to try to find a more fundamental theory
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that explains what the phenomenon we call life.
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And then it should explain certain attributes
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and you end up having a really different framing
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than the way people usually talk.
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So the way I talk about it three different ways.
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Life is how information structures matter
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across space and time.
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Life is, I don't know, this one's from you actually,
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simple machines constructing more complex machines.
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And the other one is the physics of existence,
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so to speak, which is life is the mechanism
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the universe has to explore the space of what's possible.
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That's my favorite.
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So can I, yeah, yeah, can I add on to that?
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Okay, can you say the physics one again?
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Physics of existence.
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Yeah, the physics of existence.
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I don't know what to call it.
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If you think of all the things that could exist,
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only certain things do exist.
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And I think life is basically the universe's mechanism
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of bringing things into physically existing
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in the moment now.
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Yeah, and what's another one?
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So we were debating this the other day.
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So if you think about a universe that has nothing in it,
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that's kind of hard to conceive of, right?
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Because, and this is where physicists really go wrong.
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They think of a universe with nothing in it, they can't.
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But nonexistence is really hard to think.
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Nonexistence, yeah.
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And then you think of a universe with everything in it,
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that's really hard.
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And you just have this white blob, right?
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It's just everything.
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But the fact we have discrete stuff in the universe,
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Beyonce planets, so you've got stars, space, planet stuff,
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right, the boring stuff, but I would define life
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or say that life is where there are architectures,
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any architectures, and we should stop fixating
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on what is building the architectures to start with.
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And the fact that the universe has discrete things
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and it is completely mind blowing.
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If you think about it for one second,
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the fact there's any objects at all,
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and there's, because for me, the object is a proxy
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for a machine that built it,
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some information being moved around,
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actuation, sensing, getting resource,
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and building these objects.
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So for me, everyone's been obsessing about the machine,
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but I'm like, forget the machine, let's see the objects.
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And I think in a way that assembly theory,
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we realized maybe a few months ago
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that assembly theory actually does account for the soul
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and the objects, not mystically like say,
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Sheldrake's morphic resonance,
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or Leibniz's monadology, seeing souls in things.
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But when you see an object, and I've said this before,
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but this object is evidence of thought,
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and then there's a lineage of those objects.
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So I think what is fascinating is that,
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you put it much more elegantly,
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but the barrier between life and non life
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is accruing enough memories to then actuate.
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So what that means is there are contingency,
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there are things that happen in the universe get trapped,
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these memories then have a causal effect on the future.
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And then when you get those concentrated in a machine,
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and you're actually able in real time,
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able to integrate the past, the present with the future,
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and do stuff, that's when you are most alive.
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You being the machine.
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Wait a minute, why is the object,
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so one of the ways to define life,
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that Sarah said, is simple machines
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creating complex machines.
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So there's a million questions there.
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So how the hell does a simple machine
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create a complex machine?
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So this is what we were talking about at the beginning,
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is you have the minimum replicator, so a molecule.
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So this is what I was trying to convince Sarah
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of the mechanism get there years ago, I think,
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but then you've been building on it and saying,
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you have a molecule that can copy itself,
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but then there has to be some variability,
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otherwise it's not gonna get more functional.
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So you need to add bits on.
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So you have a minimum molecule that can copy itself,
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but then it can add bits on,
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and that can be copied as well,
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and those add ons can give you additional function,
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to be able to acquire more stuff to exist.
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So existence is weird,
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but the fact that there is existence is why there is life,
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and that's why I realized a few days ago
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that there must be, that's why alien life
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must be everywhere, because there is existence.
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Is there a conservation of cheeky stuff happening?
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So how can you keep injecting more complex things?
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Doesn't the machine that creates the object
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need to be as or more powerful than the things it creates?
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So how can you get complexity from simplicity?
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So the way you get complexity from simplicity
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is that you, I'm just making this up,
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but this is kind of my notion,
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and you have a large volume of stuff,
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so you're able to get seeds, if you like,
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random cues from the environment.
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So you just use those objects
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to basically write on your tape, ones and zeros, whatever.
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And that is necessarily rich, complex, okay?
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But it has a low assembliness,
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but even though it has a high assembly number,
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we can talk about that.
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But then when you start to then integrate
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that all into a smaller volume, as over time,
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and you become more autonomous,
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you then make the transition.
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I don't know what you think about that.
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I think the easiest way to think about it is actually,
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which I know is a concept you hate, but I also hate,
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which is entropy, but people are more familiar with entropy
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than what we talk about in assembly theory.
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And also the idea that, like, say physics as we know it
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involves objects that don't exist across time,
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or as we would say, low memory objects.
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So one of the key distinctions that is...
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Low memory objects.
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Yeah, so physics is all...
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Physicists are low memory objects.
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Low memory objects.
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Physicists are creators of low memory objects
link |
or manipulators of low memory objects.
link |
It's a very nice way of putting it.
link |
Okay, sorry, go ahead.
link |
Yeah, no, it's okay.
link |
Sorry to keep interrupting.
link |
No, no, no, it's fine.
link |
I like it too, it's very funny.
link |
But I think it's a good way of phrasing it
link |
because I think this kind of idea we have
link |
in assembly theory is that, you know,
link |
physics as we know it has basically removed time
link |
as being a physical observable of an object.
link |
And the argument I would make is that
link |
when you look at things like water bottles or us,
link |
we're actually things that exist
link |
that have a large extent in time.
link |
So we actually have a physical size and time,
link |
and we measure that with something called
link |
the assembly index in molecules,
link |
but presumably everyone should have sort of a,
link |
do you want to explain what assembly?
link |
Yeah, let's, you know what?
link |
Let's step back and start at the beginning.
link |
What is assembly theory?
link |
Lee sent me some slides.
link |
There's a big sexy paper coming out probably.
link |
Maybe, I don't know.
link |
We've almost finished it.
link |
Almost, almost finished it.
link |
That's also a summary of science.
link |
We're almost done.
link |
Well, no, no, we're almost done.
link |
It's the history of science.
link |
We are ready to start an interesting discussion
link |
You're the machine that created the object,
link |
and we'll see what the object takes us.
link |
All right, so what is assembly theory?
link |
Yeah, well, I think the easiest way
link |
for people to understand it is to think about
link |
assembly and molecules,
link |
although the theory is very general.
link |
It doesn't just apply to molecules.
link |
And this was really Lee's insight,
link |
so it's kind of funny that I'm explaining it, but.
link |
Okay, all right, I'm ready, I'm ready.
link |
You have to tell me where I get the check marks minus,
link |
It's your theory as well.
link |
But imagine a molecule,
link |
and then you can break the molecule apart
link |
into elementary building blocks.
link |
They happen to be bonds.
link |
And then you can think of all the ways,
link |
for molecular assembly theory,
link |
you can think of all the ways
link |
of building up the original molecule.
link |
So there's all these paths that you can assemble it.
link |
And the sort of rules of assembly is
link |
you can use pieces that have been generated already.
link |
So it has this kind of recursive property to it.
link |
And so that's where kind of memory
link |
comes into assembly theory.
link |
And then the assembly index is
link |
the shortest path in that space.
link |
So it's supposed to be the minimal amount of history
link |
that the universe has to undergo
link |
in order to assemble that particular object.
link |
And the reason that this is significant is
link |
we figured out how to measure that
link |
with a mass spec in the lab.
link |
And we had this conjecture
link |
that if that minimal number of steps
link |
was sufficiently large,
link |
it would indicate that you required a machine
link |
or a system that had information
link |
about how to assemble that specific object
link |
because the combinatorial space of possibilities
link |
is getting exponentially large
link |
as the assembly index is increasing.
link |
So it's just, sorry to interrupt,
link |
so that means there's a sufficiently high assembly index
link |
that if observed in an object
link |
is an indicator that something lifelike created it
link |
or is the object itself lifelike?
link |
But you might want to make the distinction
link |
that a water bottle is not life,
link |
but it would still be a signature
link |
that you were in that domain of physics
link |
and that I might be alive.
link |
So there will be potentially a lot of arguments
link |
about where the line, at which assembly index
link |
does interesting stuff start to happen.
link |
The point is we can make all the arguments,
link |
but it should be experimentally observable
link |
and Lee can talk more about that part of it.
link |
But the point I want to make about it is
link |
there was always this intuition that I had
link |
that there should be some complexity threshold
link |
in the universe above which you would start to say
link |
whatever physics governs life actually becomes operative.
link |
And I think about it a little bit
link |
like we have Planck's constant,
link |
and we have the fine structure constant.
link |
And then this sort of assembly threshold
link |
is basically another sort of potentially constant of nature.
link |
It might depend on the specific features of the system,
link |
but which we debate about sometimes.
link |
But then when you're past that,
link |
you have to have some other explanation
link |
than the current explanations we have in physics,
link |
because now you're in high memory.
link |
The things actually require time for them to exist
link |
and time becomes a physical variable.
link |
The path to the creation of the object is the memory.
link |
So you need to consider that.
link |
Yeah, but the point is that's a feature of the object.
link |
So when I think of all the things in this room,
link |
we see the projection of them as a water bottle,
link |
but assembly theory would say that this is a causal graph
link |
of all the ways the universe can create this thing.
link |
That's what it is as an object.
link |
And we're all interacting, a causal graph.
link |
And most of the creativity in the biosphere
link |
is because a lot of the objects that exist now
link |
are huge in their structure across time.
link |
Four billion years of evolution to get to us.
link |
Is it possible to look at me
link |
and infer the history that led to me?
link |
If you, you as an individual might be hard.
link |
You as a representative of a population of objects
link |
that have high assembly
link |
with similar causal history and structure
link |
that you can communicate with, i.e. other humans,
link |
you can infer a lot probably.
link |
Yeah, also with them.
link |
Which we do genomically even.
link |
I mean, it's not like,
link |
we have a lot of information in us,
link |
we can reconstruct histories from.
link |
Assembly is saying something slightly deeper.
link |
Yeah, one thing to add.
link |
I mean, it's not just about the object,
link |
but the objects occur
link |
and not just objects with high assembly number,
link |
because you can have random things
link |
that have a high assembly number,
link |
but they must have,
link |
there must be a number of identical copies.
link |
So you know you're getting away from the random,
link |
because you could take a snapshot.
link |
This is why, it's not I hate entropy,
link |
I love entropy when used correctly,
link |
but it's about the problem of entropy,
link |
you have to have a labeler.
link |
And so you can label the beginning and the end,
link |
the start and the finish, you know,
link |
where what you can do in assembly is say,
link |
oh, I have a number of objects in abundance.
link |
They all have these features.
link |
And then you can infer.
link |
And one of the things that we debated a lot,
link |
particularly during lockdown,
link |
because I almost went insane trying to crush the,
link |
produce the assembly equation.
link |
So we came up with the assembly equation.
link |
I had, just imagine this.
link |
So you have a string where,
link |
actually it makes me sick trying to remember it.
link |
It was so, it did my head in for a long time.
link |
Yeah, because I couldn't,
link |
so if you just have a string of say words,
link |
say, you know, a series of words, series of letters.
link |
So you just have A, A, A, B, B, B, C, C, C, D, D, D.
link |
And you find that object and you just have four A's,
link |
four B's, four C's, four D's together, boom.
link |
Then, and that you measured that.
link |
So you physically measured that string of letters.
link |
Then what you could do is you can infer sub graphs
link |
of maybe the four A's, the four B's,
link |
the four C's and the four C's,
link |
but you don't see them in the real world.
link |
You just infer them.
link |
And I really got stuck with that
link |
because there's a problem to try and work out
link |
what's the difference between a long,
link |
you know, a physical object
link |
and this assembly space of the objects
link |
that we realized the best way to put that is infer in time.
link |
So although we can't infer your entire history,
link |
we know at some point the four A's were made,
link |
the four B's was made, the four C's were made,
link |
the four D's were made and they all got added together.
link |
And that's one really interesting thing
link |
that's come out of the theory,
link |
but the killer when we knew we were going beyond
link |
beyond standard complexity theories,
link |
but incredibly successful is that we realized
link |
we could start to measure these things
link |
for real across domains.
link |
So the assembly index is actually an intrinsic property
link |
of all stuff that you can break into components,
link |
particularly molecules are good
link |
because you can break them up
link |
into smaller molecules, into atoms.
link |
The challenge will be making that more general
link |
across all the domains,
link |
but we're working on it right now
link |
and I think the theory will do that.
link |
So components, domains,
link |
so you're talking about basically measuring
link |
the complexity of an object in what,
link |
biology, chemistry, physics,
link |
that's what you mean by domains.
link |
Complexity of tests.
link |
Sociology. Complexity of computers.
link |
Complexity of memes, you know.
link |
What is that, ideas?
link |
Yeah, I mean, so one of the.
link |
Ideas are objects in assembly theory.
link |
They're physical things.
link |
They're just features of the causal graph.
link |
I mean, the fact that I can talk to you right now
link |
is because we're exchanging structure
link |
of our assembly space.
link |
So conversation is the exchanging structures
link |
in assembly space.
link |
What is assembly space?
link |
When I started working on origins of life,
link |
I was writing about something called top down causation,
link |
which a lot of like philosophers are interested in
link |
and people that worry about the mind body problem.
link |
But the whole idea is, you know,
link |
if we have, you know, the microscopic world of physics
link |
is causally complete,
link |
it seems like there's no room for higher level causes
link |
like our thoughts to actually have any impact on the world.
link |
And that didn't, that seems problematic
link |
when you get to studying life and mind
link |
because it does seem that quote unquote,
link |
emergent properties do matter to matter.
link |
And then there's this other sort of paradoxical situation
link |
where information looks like it's disembodied.
link |
So we talk about information,
link |
like it can just move from any physical system
link |
to any other physical system.
link |
And it doesn't require,
link |
like you don't have to specify anything about the substrate
link |
to talk about information.
link |
And then there's also the way we talk about mathematics
link |
is also disembodied, right?
link |
Like the platonic world of forms
link |
and I think all of those things are hinging
link |
that we really don't know how to think about abstractions
link |
as physical things.
link |
And really, I think what assembly theory is pointing to
link |
is what we're missing there is the dimension of time.
link |
And if you actually look at an object
link |
being extended across time,
link |
what we call information and the things that look abstract
link |
are things that are entangled
link |
in the histories of those objects.
link |
They're features of the overlapping assembly space.
link |
So they look abstract because they're not
link |
part of the current structure,
link |
but they're part of the structure
link |
if you thought about it as like the philosophical concept
link |
of a hyperobject, an object that's too big in time
link |
for us to actually to resolve.
link |
And so I think information is physical.
link |
It's just physical in time, not in space.
link |
Too hyperobject, too difficult for us to resolve.
link |
So we're supposed to think about of life
link |
as this thing that stretches through time
link |
and there's a causation chain that led to that thing.
link |
And then you're trying to measure something
link |
with the assembly index about properties of that.
link |
The assembly index is the ordering,
link |
like you could think of it as like a partial ordering
link |
of all the things that can happen.
link |
So in thermodynamics, we coarse grain things
link |
by temperature and pressure.
link |
In assembly theory, we coarse grain
link |
by the number of copies of an object
link |
and the assembly index, which is basically,
link |
if you think of the space of all possible things,
link |
it's like a depth of how far you've gone into that space
link |
and how much time was required to get there.
link |
In the shortest possible version.
link |
The shortest possible version.
link |
Not average, because can't you just 3D?
link |
You're gonna kill me with that question.
link |
Not 3D, can't you always 3D print the thing?
link |
Let's like stab him in the heart.
link |
No, because I had such a fight.
link |
So Sarah's team and my team are writing this paper
link |
at the moment and.
link |
I think we kind of share the, at the beginning,
link |
you were like, no, that's not right.
link |
Oh yeah, that's right.
link |
And we're doing this for a bit.
link |
And then the problem is when you build a theory
link |
and build the intuition,
link |
there's some certain features, right,
link |
of the theory that almost felt like
link |
I was being religious about saying,
link |
right, you have to do this.
link |
A good assembly theorist does this, does this, does this.
link |
And Sarah's postdoc, Daniel, and my postdoc, Abhishek,
link |
and they were both.
link |
They're both brilliant.
link |
They're brilliant, but they were like,
link |
no, we don't buy that.
link |
And I was like, it is, they were like,
link |
well, Lee, actually, I thought you were the first
link |
to say that, you know, you can't,
link |
if you can't explain it, it doesn't,
link |
and you can't do an experiment that doesn't exist.
link |
And that saved me.
link |
And I said to Abhishek,
link |
Abhishek's my postdoc in Glasgow,
link |
Daniel is Sarah's postdoc in ASU.
link |
I was like, I have the experimental data.
link |
So when I basically take the molecules
link |
and chop them up in the mass spec,
link |
the assembly number is never the average.
link |
It's always the shortest.
link |
It's an intrinsic property.
link |
And then the penny drop for Abhishek said, okay.
link |
So I had these things that we had to believe
link |
to start with or to trust,
link |
and then we'd done the math and it comes out.
link |
And they now have the shortest path, actually.
link |
It's up, it explains why the shortest path.
link |
Here's why the shortest path is important, not the average.
link |
The shortest path needs you to identify
link |
when the universe has basically got a memory,
link |
So what you want to be able to do is to say,
link |
what is the minimum number of features
link |
that I want to be able to see in the universe?
link |
When I find those features,
link |
I know the universe has had a coherent memory
link |
and is basically alive.
link |
And so that gives you the lower bound.
link |
So that's like, of course there's going to be other paths.
link |
We can be more ridiculous, right?
link |
We can have other parts, but it's just the minimum.
link |
So probabilistically at the beginning,
link |
because assembly theory was built
link |
as a measure for biosignatures, I needed to go there.
link |
And then I realized it was intrinsic.
link |
And then Sarah realized it was intrinsic
link |
and these hyperobjects were coming.
link |
And we were kind of fusing that notions together.
link |
And then the team were like, yeah,
link |
but if I have enough energy and I have enough resources,
link |
I might not take the shortest path.
link |
I might go a bit longer.
link |
I might take a really long path
link |
because it allows me then to do something else.
link |
So what you can do is, let's say
link |
I've got two different objects, A and B,
link |
and they both have different shortest paths to get them.
link |
But then if you want to make A and B together,
link |
they will have a compromise.
link |
So in the joint assembly space, that might be an average,
link |
but actually it's the shortest way
link |
you can make both A and B
link |
with a minimum amount of resource in time.
link |
So suddenly you then layer these things up.
link |
And so the average becomes not important,
link |
but as you literally overlap those sets,
link |
you get a new shortest path.
link |
And so what we realized time and time again
link |
when we're doing the math,
link |
the shortest path is intrinsic, is fundamental,
link |
and is measurable, which is kind of mind blowing.
link |
So what we're talking about, some basic ingredients,
link |
maybe we'll talk about that, what those basic ingredients
link |
could be and how many steps, when you say shortest path,
link |
how many steps it takes to turn those basic ingredients
link |
into the final meal.
link |
So how to make a, what's the shortest way to make a pizza?
link |
And a pizza and a pie together.
link |
So there's a lot of ways.
link |
There's the shortest way,
link |
and then you take the full spectrum of ways
link |
and there's probably an average duration
link |
for a noob to make an apple pie.
link |
Is the average interesting still?
link |
If you measure the average length of the path
link |
to assemble a thing, does that tell you something
link |
about the way nature usually does it?
link |
Versus something fundamental about the object,
link |
which I think is what you're aiming at
link |
with the assembly index.
link |
Yeah, I mean, look, we all have to quantify things.
link |
The minimum path gives you the lower bounds.
link |
You know you're detecting something.
link |
You know you're inferring something.
link |
The average tells you about really how the objects
link |
are existing in the ecosystem or the technology.
link |
And there has to be more paths explored
link |
because then you can happen upon other memories
link |
and then condense them down.
link |
I'm not making too much sense, but if you look and say,
link |
let's just say, I mean, maybe we're gonna get
link |
to alien civilizations later, right?
link |
But I would argue very strongly
link |
that alien civilization A and alien civilization B,
link |
they're different assembly spaces.
link |
So they're kind of gonna be a bit messed up
link |
if they happen to come one another,
link |
only when they find some joint overlap in their technology,
link |
because if aliens come to us and they don't share
link |
any of the causal graph we've showed,
link |
but hopefully they share the periodic table
link |
and bonds and things,
link |
that we're gonna have to really think about the language
link |
to talk to us aliens by inferring,
link |
by using assembly theory to infer their language,
link |
their technology, and other bits and bobs.
link |
And the shortest path will help you do that quickly.
link |
All right, so all aliens in this causality graphs
link |
have a common ancestor in the...
link |
If the building blocks are the same,
link |
which means they live in the same universe as us.
link |
So this is the assumption.
link |
It depends on how far back in time you go, though.
link |
But the universe has all the same building blocks.
link |
And we have to assume that.
link |
So at least there's not different classes
link |
of causality graphs, right?
link |
The universe doesn't just say like,
link |
here you get the red causality graph,
link |
and you get the blue one.
link |
These basic ingredients,
link |
and they're geographically constrained,
link |
or constrained in space or time, or something like that.
link |
They're constrained in time
link |
because only by the virtue of the fact
link |
that you need enough time to have passed
link |
for some things to exist.
link |
So the universe has to be big enough in time
link |
So just one point on the shortest path
link |
versus the average path,
link |
which I think we'll get to this,
link |
is you had a nice way of saying it's like
link |
the minimal compression is the shortest path
link |
for the universe to produce that.
link |
But it's also like the first time
link |
in the ordering of events
link |
that you might expect to see that object.
link |
But the average path tells you something
link |
about the actual steps that were realized,
link |
and that becomes an emergent property
link |
of that object's interaction with other objects.
link |
So it's not an intrinsic feature of that object.
link |
It's a feature of the interactions with other things.
link |
And so one of the nice features of assembly
link |
is you've basically gotten rid of,
link |
you just look at the things that exist,
link |
and you've gotten rid of the mechanisms
link |
for constructing them in some sense.
link |
Like the machines are not as important
link |
in the current construction of the theory,
link |
although I would like to bridge it
link |
to some ideas about constructors.
link |
But then you can only communicate with things
link |
as Lee was saying,
link |
if you have some overlap in the past history.
link |
So if you had an alien species
link |
that had absolutely no overlap,
link |
then there would be no means of communication.
link |
But as we progress further and further in time
link |
and more things become possible
link |
because the assembly spaces are larger,
link |
because you can have a larger assembly space
link |
in terms of index and also just the size of the space,
link |
because it's exponentially growing,
link |
then more things can happen in the future.
link |
And the example I like to give is actually
link |
when we made first contact with gravitational waves,
link |
because that's an alien phenomenon
link |
that's been permeating our planet,
link |
not alien in life phenomenon,
link |
but alien like something we had never knew existed.
link |
It's been like there's gravitational waves
link |
rippling through this room right now,
link |
but we had to advance to the level of Einstein
link |
writing down his theory of relativity
link |
and then 100 years of technological development
link |
to even quote unquote see that phenomena.
link |
So the, okay, to see that phenomena,
link |
our causal graph have to start intersecting.
link |
Yeah, we needed the idea to emerge first,
link |
the abstraction, right?
link |
And then we had to build the technology
link |
that could actually observe features of that abstraction.
link |
So the nice promising thing is over time,
link |
the graph can grow so we can start overlapping eventually.
link |
Yeah, so the interesting feature of that graph
link |
is there was an event 1.4 billion years away
link |
of a black hole merger that we detected on our detector.
link |
And now suddenly we're connected
link |
through this communication channel
link |
with this distant event in our universe
link |
that if you think about 1.4 billion years ago,
link |
what was happening on this planet
link |
or even further back in time,
link |
that there's common physics underlying all of those events,
link |
but even for those two events to communicate.
link |
Now I understand what you were going on about
link |
Yeah, I'm sorry, this is a really abstract example,
link |
Your causal graphs are now overlapping.
link |
Well, let's just say now our causal graphs
link |
are overlapping in the deep past.
link |
No, I like it, so you made it.
link |
I totally missed it.
link |
Oh, the 1.6 billion.
link |
You made a connection with it.
link |
No, I do like that.
link |
No, no, you can tell me what your epiphany is now.
link |
And I should get the jokes before 30 seconds after, so.
link |
No, it's all right.
link |
The joke from two minutes ago.
link |
I'm slow on the uptake here.
link |
I wasn't able to comprehend
link |
what you were talking about when saying
link |
the channel communicating to the past.
link |
But what you're saying is we were able to infer
link |
what happened 1.4 billion years ago.
link |
We detected the gravity wave.
link |
I mean, I think it's amazing that at that time,
link |
we weren't even, we were just becoming multicellular,
link |
And then we progressed from multicellularity
link |
through to technology and built the detector
link |
and then we just extrapolate backwards.
link |
So, although we didn't do anything back to the graph
link |
back in time, we understood this existence
link |
then overlapped going forward.
link |
Well, that's because our graphs are larger.
link |
Yeah, but that means that has a consequence.
link |
One of the things I was trying to say is I think,
link |
I don't know, Sarah might be, she can correct me,
link |
information first and I'm a object first kind of guy.
link |
So, I mean, there's things that get constructed.
link |
There has to be this transition in random constructions.
link |
So when the object that's being constructed by the process
link |
bakes in that memory and those memories then add on
link |
and add on and add on.
link |
So as it becomes more competent and life is about
link |
taking those memories and compressing them,
link |
increasing their autonomy.
link |
And so I think that, like the cell that we have
link |
in biology on earth is our way of doing that,
link |
that really the maximum ability to take memories
link |
and to act on the future.
link |
Oh, I think that's mathematics.
link |
No, mathematics doesn't exist.
link |
No, but that's the point.
link |
The point is that abstractions do exist.
link |
They're real physical things.
link |
We call them abstractions.
link |
But the point about mathematics that I think is,
link |
so I don't disagree that I think you're object first
link |
and I'm information first, but I think I'm only
link |
information first in the sense that I think the thing
link |
that we need to explain is what abstractions are
link |
and what they are as physical things
link |
because of all of human history,
link |
we've thought that there were these properties
link |
that are disembodied, exist outside of the universe
link |
and really they do exist in the universe
link |
and we just don't understand what their physics is.
link |
So I think mathematics is a really good example.
link |
We do theoretical physics with math,
link |
but imagine doing physics of math
link |
and then thinking about math as a physical object.
link |
And math is super interesting.
link |
I think this is why we think it describes reality so well
link |
because it's the most copyable kind of information.
link |
It retains its properties
link |
when you move it between physical media,
link |
which means that it's very deep.
link |
And so it seems to describe the universe really well,
link |
but it probably is because it's information
link |
that's very deep in our past.
link |
And it's just, we invented a way of communicating it
link |
very effectively between us.
link |
Isn't math more fundamental?
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Isn't the assembly of the graph,
link |
isn't basically, I sound completely boring.
link |
It's like math, assembly theory invented math, but it did.
link |
So what is math exactly?
link |
It's a nice simplification,
link |
a simple description of what?
link |
So we have a computer scientist,
link |
a physicist, and a chemist here.
link |
I think the chemist is gonna define math
link |
and you guys can correct me.
link |
Lay in on us, Lee.
link |
I think the ability to label objects
link |
and place them into classes
link |
and then do operations on the objects is what math is.
link |
what does it mean to be object first
link |
versus information first?
link |
So what's the difference between object and information
link |
when you get to that low fundamental level?
link |
Well, I might change my view.
link |
So I'm stuff first, the stuff.
link |
And then when stuff becomes objects,
link |
it has to invent information.
link |
And then the information acts on more stuff
link |
and becomes more objects.
link |
So I think there is a transition to information
link |
that occurs when you go from stuff to objects.
link |
You mean time though, I think.
link |
Information is emergent.
link |
Information is actionable memories from the universe.
link |
So when memories become actionable, that's information.
link |
But there's always memory, but it's not actionable.
link |
And then it's not information.
link |
And actionable is what you can create.
link |
If you can't use it, then it's not information.
link |
If you can't transmit it,
link |
if it doesn't have any causal consequence.
link |
Falls in the forest.
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I don't understand.
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Why is that not information?
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It's not information.
link |
It's stuff happening, but it's not causal.
link |
Yeah, yeah, we can.
link |
But it's happening.
link |
Happening requires information.
link |
No, no, no, no, no.
link |
Stuff is always happening.
link |
No, this is where the physicists
link |
and the math petitions get themselves in a loop
link |
because I think the universe, I mean,
link |
I think say Max Tegmark is very playful
link |
and say like the universe is just math.
link |
Well, the universe is just math.
link |
Then we might as well not bother having any conversation
link |
because the conversation already written,
link |
we just might as well go to the future and say,
link |
can you just give us the conversations happened already?
link |
So I think the problem is that math petitions
link |
are so successful at labeling stuff
link |
and so successful understanding the stuff
link |
through those labels,
link |
they forget that actually those labels had to emerge
link |
and that information had to be built on those memories.
link |
So memory in the universe, so constraints, graph,
link |
when they become actionable
link |
and the graph can loop back on itself
link |
or interact with other graphs and they can intersect,
link |
those memories become actionable
link |
and therefore they're information.
link |
And I think you just changed my mind
link |
on something pretty big, but I don't have a pen.
link |
So I can't write, I'm gonna write it down later,
link |
but roughly the idea is like you've got these two graphs
link |
of objects of stuff that you have memories
link |
and then when they intersect
link |
and then they can act on each other,
link |
that's maybe the mechanism by which information is then,
link |
so then you can then abstract.
link |
So when one graph can then build another graph and say,
link |
hey, you don't have to go through the nonsense
link |
we had to go through.
link |
Here's literally the way to do it.
link |
Stuff always comes first,
link |
but then when stuff builds the abstraction,
link |
the abstractions can be then teleported
link |
And the abstractions is the looping back power.
link |
Am I making, I don't know, I got stuck.
link |
Yeah, so first, God made stuff.
link |
Then after that, when you start to be able
link |
to form abstractions, that's when the information.
link |
God is the memory the universe can remember.
link |
God is the memory the universe can remember.
link |
Otherwise, there's no, wait, did you?
link |
Someone's gonna be deciphering that statement
link |
hundreds of years from now, what the hell does that mean?
link |
What does the humans mean by this?
link |
Look, don't diss my one liners.
link |
I took me 15 seconds to come up with that.
link |
I don't know what it means.
link |
What does it mean?
link |
Okay, wait, we need to, how do we get onto this?
link |
We were time, causality, mathematics.
link |
So what is mathematics in this picture of stuff,
link |
objects, memory, and information?
link |
What exactly is mathematics?
link |
It's the most efficient labeling scheme
link |
that you can apply to lots of different graphs.
link |
Labeling scheme doesn't make it sound useful.
link |
Yep, sure, please.
link |
Have you rejected my definition of mathematics?
link |
Yeah, no, it's all right.
link |
No, I mean, I think we have a problem, right?
link |
Cause we can't not be us,
link |
like we're stuck in the shells we are
link |
and we're trying to observe the world.
link |
And so mathematics looks like it has certain properties.
link |
And I guess the thought experiment I find is useful
link |
is to try to imagine if you were outside of us
link |
looking at us as physical systems using mathematics,
link |
what would be the specific features you associate
link |
to the property of understanding mathematics
link |
and being able to implement it in the universe, right?
link |
And when you do that,
link |
mathematics seems to have some really interesting properties
link |
relative to other kinds of abstraction
link |
we might talk about like language or artistic expression.
link |
One of those properties is the one I mentioned already
link |
that is really easy to copy between physical media.
link |
So if I give you a mathematical statement,
link |
you almost immediately know what I mean.
link |
If I tell you the sky is blue,
link |
you might say, is it gold ball blue?
link |
What color blue do you mean?
link |
And you have a harder time visualizing what I actually mean.
link |
So mathematics carries a lot of meaning with it
link |
when it's copied between physical systems.
link |
It's also the reason we use it to communicate with computers.
link |
And then the second one is it retains its property
link |
of actually what it can do in the universe when it's copied.
link |
So the example I like to give there
link |
is think about like Newton's law of gravitation.
link |
It's actually, it's a compressed regularity
link |
of a bunch of phenomena that we observe in the universe,
link |
but then that information actually is causal in a sense
link |
that it allows us to do things we wouldn't be able to do
link |
without that particular knowledge
link |
and that particular abstraction.
link |
And in this case, like launch satellites to space
link |
or send people to Mars or whatever it is.
link |
So if you look at us from the outside and you say,
link |
what is it for physical systems
link |
to invent a thing called mathematics
link |
and then to use and then it to become a physical observable,
link |
mathematics is kind of like
link |
the universally copyable information
link |
that allows new possibility spaces
link |
to be open in the future
link |
because it allows this kind of ability
link |
to map one physical system to another
link |
and actually understand that the general principles.
link |
So is it helping the overlap of causal graphs then
link |
Oh, I think that's the explanation for what it is
link |
in terms of the physical theory of assembly
link |
would be some feature of the structure
link |
of the assembly spaces of causal graphs
link |
and their relationship to each other.
link |
So for example, and I mean, this is things
link |
that we're gonna have to work out over the next few years.
link |
I mean, we're in totally uncharted conceptual territory
link |
here, but as is usual, diving off the deep end,
link |
but I would expect that we would be able to come up
link |
with a theory of like, why is it that some physical systems
link |
can communicate with each other?
link |
Like language, language is basically
link |
because we're objects extended over time
link |
and some of the history of that assembly space
link |
actually overlaps.
link |
And when we communicate,
link |
it's because we actually have shared structure
link |
in our causal history.
link |
Let me have another quick go at this, right?
link |
So I think we all agree.
link |
So I think we take mathematics for granted
link |
because we've gone through this chain, right?
link |
Of, you know, we all share a language now, okay?
link |
And we can, well, we share language,
link |
so we have languages that we can make interoperable.
link |
And so whether you're speaking, I don't know,
link |
all the different dialects of Chinese,
link |
all the different dialects of English, French, German,
link |
whatever, you can interconvert them.
link |
The interesting thing about mathematics now
link |
is that everybody on planet Earth, every human being
link |
and computers share that common language.
link |
That language was constructed by a process in time.
link |
So what I'm trying to say is assembly invented math
link |
is those, right from the, you know,
link |
mathematics didn't occur, it didn't exist before life.
link |
Abstraction was invented by life, right?
link |
That doesn't mean that the universe wasn't capable
link |
of mathematical things.
link |
Wait a minute, can we just ask that old famous question,
link |
is math invented or discovered?
link |
So when you say assembly invented, or whatever.
link |
It means it's just.
link |
Well, someone might just say assembly
link |
is a mathematical theory, but sorry.
link |
Are we arguing? Exactly.
link |
Are we arguing now?
link |
That's what it sounds like.
link |
Are we discovering mathematics?
link |
No, well, yes and no.
link |
And you call mathematics a language
link |
that we're developing. I would say that,
link |
look, I'm pretty sure that there are some very common
link |
seeds of mathematics in the universe, right?
link |
But actually not the mathematics that we are finding now
link |
is not discovered, it's invented.
link |
And, but even though I think those two terms
link |
are very triggering, and I don't think
link |
they're necessarily useful,
link |
because I think that what people do,
link |
the mathematicians that say, oh, mathematics was discovered
link |
because they live in a universe where there is no time
link |
and it just all exists.
link |
But what I'm saying is, and I think in the same way
link |
you can create, let's say I'm gonna go and create
link |
and make a piece of art, did I make that piece of art
link |
or did I discover it?
link |
Like inventing the aeroplane.
link |
Did I invent the aeroplane?
link |
Let's stick with the aeroplane.
link |
The aeroplane is a good one.
link |
Let's say, did I discover the aeroplane?
link |
Well, in a way, the universe discovered the aeroplane
link |
because it's just chucked a load of atoms together
link |
and a load of random human beings want to do stuff
link |
and then we discover the aeroplane
link |
in the space of all the possibilities.
link |
But here's the thing, when the space of possibilities
link |
is so vast, infinite almost, and you're able to actualize
link |
one of those in an object, then you are inventing it.
link |
So in mathematics, because there are infinite number
link |
of theorems, the fact you're actually pulling,
link |
there's no difference between inventing
link |
a mathematical structure and inventing the aeroplane.
link |
They're the same thing, but that doesn't mean
link |
that now the aeroplane exists in the universe,
link |
it's something weird about the universe.
link |
So I think that the more, this is the thing
link |
that you probably, the more memory required
link |
for the object, the more invented it is.
link |
So when a mathematical theorem needs more bytes
link |
to store it, the more invented it is,
link |
and the less bytes, the more discovered it is.
link |
But everything then is invented.
link |
It's just more or less invented.
link |
The universe has to generate everything as it goes.
link |
And it wasn't there in the beginning.
link |
And the way we're thinking it,
link |
when you're thinking about the difference
link |
between invented and discovered,
link |
is because we're throwing away all the memory.
link |
So if you start to think in terms of causality and time,
link |
then those things become the same.
link |
Everything is invented.
link |
And the idea is to make everything intrinsic
link |
So I think one of the features of assembly theory
link |
is we don't wanna have external observers.
link |
There's been this long tradition in physics
link |
of trying to describe the universe from the outside
link |
and not the inside.
link |
And the universe has to generate everything itself
link |
if you do it from the inside.
link |
Assembly theory describes how the universe builds itself.
link |
Did it take you 15 seconds to say that?
link |
And to come up with that also?
link |
No, I've thought of that before.
link |
That's a good line.
link |
It's a, it's like.
link |
Oh, you're making fun of me.
link |
No, I'm not making fun, I'm having fun.
link |
There's a difference.
link |
She's inventing fun.
link |
I'm not all intimidated.
link |
And there's a causal history to that fun.
link |
You mentioned that there's no way to communicate
link |
with aliens until there's overlap in the causal graph.
link |
Communication includes being able to see them.
link |
And like, what are we, this is the question is,
link |
is communication any kind of detection?
link |
And if so, what do aliens look like
link |
as you get more and more overlap on the causal graph?
link |
You're assuming, let's assume that aliens,
link |
so when you see them and they see you,
link |
you're assuming they have vision,
link |
they have the ability to construct in 3D and in time.
link |
That's a lot of assumptions they're making.
link |
All right, let's step back.
link |
So yes, okay, you're right.
link |
So when, in the English language,
link |
when we say the word see, we mean visually,
link |
they show up to a party and it's like,
link |
oh, wow, that's an alien.
link |
That's visual, that's 3D, that's, okay.
link |
And that's also assuming scale,
link |
spatial scale of something that's visible to you.
link |
So it can't be microscopic or it can't be so big
link |
that you don't even realize that's an entity.
link |
Okay, but other kinds of detection too.
link |
I would make it more abstract and go down.
link |
I was thinking this morning about how to rewrite
link |
the Arecibo message in assembly theory
link |
and also to abandon binary.
link |
Because I don't think aliens necessarily,
link |
why should they have binary?
link |
Well, they have some basic elements
link |
with which to do information exchange.
link |
Let's make it more fundamental, more universal.
link |
So we need to think about what is the universal way
link |
of making a memory and then we should
link |
reencode Arecibo in that way.
link |
What's more basic than zeros and ones?
link |
Well, it's really difficult to get out
link |
that causal chain because we're so,
link |
so let's erase the idea of zero for a moment.
link |
It took human beings a long time
link |
to come up with the idea of zero.
link |
Now you got the idea of zero, you can't throw it away.
link |
To discover the idea of zero.
link |
To discover or invent.
link |
I don't know, but it took a long time
link |
so it was invented, that's right.
link |
Yeah, I think zero was invented, exactly.
link |
So it's not a given that aliens know what zero is.
link |
That's a massive assumption.
link |
It's a useful discovery.
link |
You're saying if you break the causal chain
link |
there might be some other more efficient way of representing.
link |
That's why I wanna meet him and ask him.
link |
But you won't be able to ask him until.
link |
So I interrupted you and I think you're making good point.
link |
I was just gonna say, well look.
link |
Rather than saying.
link |
Please internet, tweet at him for the rude interruptions.
link |
Oh, go ahead, I'm sorry.
link |
Maybe it's change.
link |
How do we, so, oh, I don't know what it's like
link |
I would like to know.
link |
What is the full spectrum of what aliens
link |
might look like to us?
link |
Now that we've laid this all on the table of like,
link |
all right, so there has to be some overlap
link |
in this causal chain that led to them.
link |
What are we looking for?
link |
What do you think we should be looking for?
link |
So you mentioned mass spec.
link |
Measuring certain objects that aliens could create
link |
or are aliens themselves.
link |
We show up to a planet or maybe not a planet.
link |
Or maybe, what the hell is the basic object
link |
we're trying to measure the assembly index of?
link |
Let's cut ourselves a break.
link |
Let's assume that they are metabolized.
link |
They've got an energy source.
link |
And they're a size that we can recognize.
link |
Let's give ourselves a break.
link |
Because there could be aliens that are so big
link |
we won't recognize we're seeing them.
link |
There might be aliens that are so small
link |
we don't yet have the ability to,
link |
we don't have microscopes that can see far enough away
link |
that just wouldn't be able to see them.
link |
So what's a good range?
link |
So let's just make a range.
link |
Let's just be very anthropocentric and say,
link |
we're gonna look for aliens roughly our size
link |
and technology our size.
link |
Because we know it's possible on Earth, right?
link |
I mean, a reasonable thing to do would be
link |
to find exoplanets that are in the same zone as Earth
link |
in terms of heat and stuff.
link |
And then say, hey, if there's that same kind of gravity,
link |
same kind of stuff, we could reasonably assume
link |
that alien life there might use a similar kind
link |
of physical infrastructure.
link |
And then we're good.
link |
So then your question becomes really relevant.
link |
Say, right, let's use vision, sound, touch.
link |
So okay, that's really nice.
link |
So that if there's a lot of aliens out there,
link |
there's a good likelihood if you match to the planet
link |
that they're going to be in the same spatial
link |
and temporal, operating in the same spatial
link |
and temporal domain as humans.
link |
Okay, within that, what do they look like visually?
link |
What do they sound like?
link |
What do they, oh god, this sounds creepy.
link |
Tastes like, what do they, oh, smell like, smell like.
link |
That sounds like our clubhouse.
link |
We was like, can we have sex with aliens?
link |
Which was basically me saying.
link |
Passionate, passionate love.
link |
But it wasn't actually about sex.
link |
It was about, is our chemistry compatible, right?
link |
Yeah, can we, yeah.
link |
Are they edible too?
link |
They could be very edible.
link |
They could be delicious.
link |
That's why I want to see some aliens, right?
link |
Because I think, are there, I think evolution,
link |
I mean, evolution exploits symmetry, right?
link |
Because why generate memory?
link |
Why generate storage, the need for storage space
link |
when you can use symmetry?
link |
So, and symmetry is quite, may be quite effective
link |
in allowing you to mechanically design stuff, right?
link |
So maybe alien, you could be reasonable to assume
link |
that aliens could have, they could be bipedal.
link |
They could be symmetric in the same way.
link |
Might have a couple of eyes or a couple of senses.
link |
We can make them, perhaps there's this whole zoo
link |
of different aliens out there.
link |
And we'll never get to be able to classify
link |
some of the weird aliens we can't interact with
link |
because they have made such weird stuff.
link |
But we are just going to look at,
link |
we're going to find aliens that look most like us.
link |
Because those are the first ones we're likely to see.
link |
But I think it's really hard to imagine
link |
what the space of aliens is because the space is huge.
link |
Because, you know, like one of the arguments
link |
that you can make about why life emerges in chemistry
link |
is because chemistry is the first scale
link |
in terms of like, you know,
link |
building up objects from elementary objects.
link |
That the number of possible things that could exist
link |
is larger than the universe can possibly make all at once.
link |
So imagine you have two planets
link |
and they're cooking some geochemistry.
link |
You know, our planet invented one kind of biochemistry.
link |
And presumably as you start building up
link |
the complexity of the molecules,
link |
the chances of the overlap in those trajectories,
link |
those causal chains being built up is probably very low.
link |
And it gets lower and lower as it gets further advanced
link |
along its evolutionary path.
link |
So I think it's very difficult to imagine
link |
predicting the technologies that aliens are gonna have.
link |
I mean, it's so, you're looking at basically
link |
planets have kind of convergent chemistry,
link |
but there's some variability.
link |
And then you're looking basically at the outgrowth
link |
into the possibility space for chemistry.
link |
So do you think we would detect the technology,
link |
the objects created by aliens before we detect the aliens?
link |
So when you're talking about measuring assembly index,
link |
don't you think we would detect the garbage first?
link |
Like at the outskirts of alien civilizations,
link |
isn't this just gonna be trash?
link |
I think I would come back to Arecibo.
link |
The Arecibo message sent from the Arecibo telescope
link |
built by Drake, I think, and Sagan.
link |
How's Arecibo spelled?
link |
And there we go, they've got that up there.
link |
That's the telescope that sent the message
link |
that you're talking about.
link |
So that message was sent where?
link |
It was beamed at a star, a specific star,
link |
and it was sent out many years ago.
link |
And what they did, so this is why I was pushing on binary,
link |
it's a binary message.
link |
I think it's a semi prime length number of characters.
link |
So I think 73 by 23, I think.
link |
And it basically represents human bit proton,
link |
binary, human beings, DNA, male and female.
link |
And it's really cool.
link |
But I'm just wondering if it could be done
link |
cause it made assumptions that aliens speak binary.
link |
Why make that assumption?
link |
Why not just assume that if the difference between physics,
link |
chemistry and biology is the amount of memory
link |
that's instead that's recordable by the substrates,
link |
then surely the universal thing,
link |
I'm gonna make some sacrilegious statement,
link |
which I think is pretty awesome for people to argue with.
link |
So this is, we're looking at an image
link |
where it's the entirety of the message encoded in binary.
link |
And then there's a probably interpretation
link |
of different parts of that image.
link |
There's a person, there's green parts.
link |
It looks like for people just listening,
link |
like a game of Tetris.
link |
So it's encoding in minimal ways,
link |
a bunch of cool information, probably.
link |
Representing all of us.
link |
So the topic's kind of teaching us how to count
link |
and then it all goes all the way down
link |
teaching you chemistry and then just says,
link |
but it makes so many assumptions.
link |
And I think if we can actually,
link |
so look, I think, I mean, Sarah's much more eloquent
link |
in expressing this, but I'll have a go
link |
and you can correct it if you want,
link |
which is like one of the things that Sarah has had
link |
a profound effect on the way I look at the origin of life.
link |
And this is one of the reasons why we're working together
link |
because we don't really care about the origin of life.
link |
We wanna make life, make aliens and find aliens.
link |
Make aliens, find aliens.
link |
I think we might have to make aliens in the lab
link |
before we find aliens in the universe, right?
link |
I think that would be a cool way to do it.
link |
So what is it about the universe that creates aliens?
link |
Well, it's selection through assembly theory,
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creating memories, because when you create memories,
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you can then command your domain.
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You can basically do stuff.
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You can command matter.
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So we need to find a way by understanding what life is
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of how the minimal way to command matter,
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how that would emerge in the universe.
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And if we want to communicate,
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I mean, maybe we don't want
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to necessarily uniformly communicate.
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What I would do perhaps if I had,
link |
is I would send out lots of probes away from Earth
link |
that have this magic way of communicating with aliens,
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get them quite a far away from Earth, plausibly deniable,
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and then send out the message
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that would then attract all the aliens,
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and then basically work out if they were friend or foe
link |
and how they wanna hang out.
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The messages being something has to do with the memories.
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Yes, like the assembly version of Arecibo,
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so that everyone in the universe
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that has been understands what life is.
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So aliens need to work out what they are.
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Once they've worked out what they are,
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they then can work out how to encode what they are,
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and then they can go out and send messages.
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It's like the universal, the Rosetta Stone
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for life in the universe is working out
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how the memories are built.
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I don't know, Sarah, you have any, well,
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whether you would agree with that.
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No, I wanted to raise a different point,
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which is about the fact that we can't see the aliens yet
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because we haven't gotten the technology.
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And presumably we think assembly theory
link |
is the right way of doing it,
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but I don't think that we know how to go
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from the kind of data you're describing, Lex,
link |
like visual data or smell
link |
to construct the assembly spaces yet.
link |
And in some ways, I think that the problem
link |
of life detection really is the same problem
link |
at the foundations of AI that we don't understand
link |
how to get machines to see causal graphs,
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to see reality in terms of causation.
link |
And so I think assembly and AI
link |
are gonna intersect in interesting ways, hopefully,
link |
but the sort of key point,
link |
and I've been trying to make this argument more recently,
link |
I might write an essay on it,
link |
is people talk about the great filter, right?
link |
And which is, again, this doomsday thing
link |
that people wanna say there's no aliens out there
link |
because something terrible happened to them.
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And it matters whether that's in our past or our future
link |
as to the longevity of our species, presumably,
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which is why people find it interesting.
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But I think it's not a physical filter.
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It's not like things go extinct.
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I think it's literally,
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we don't have the technology to see them.
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And you could see that with microscopes.
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I mean, we didn't know there were microbes on this table
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or tables for thousands of years or telescopes.
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Like there's so much of the universe we can't see.
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And then basically what we have done as a species
link |
is outsource our physical perceptions to technology,
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building microscopes based on our eyes,
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and building seismometers based on our sense of feelings,
link |
like feel earthquakes and things.
link |
And AI is basically we're trying to outsource
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what's actually happening in our thinking apparatus
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into machines now and to technological devices.
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And maybe that's the key technology
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that's gonna allow us to see things like us
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and see the universe in a totally different way.
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But you kind of mentioned the great filter.
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Do you think there's a way through technology
link |
to stop being able to see stuff?
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So can you take a step backwards?
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Did you imply that with the great, so like?
link |
Well, no, I mean, I think there's a great perceptual filter
link |
in the sense that a example of life evolving on a planet
link |
over billions of years has to acquire
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a certain amount of knowledge and technology
link |
to actually recognize the phenomena that it is.
link |
Well, that's the sense I have is,
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I mean, you talk with physicists, engineers in general,
link |
there's this kind of idea that we have
link |
most of the tools already to hear the signal.
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But to me, it feels like we don't have any of the tools
link |
to see the signal.
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No, we don't know what we're doing, yeah, I agree.
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That's the biggest, like to hear.
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We don't have the tools to really hear, to see.
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Aliens are everywhere.
link |
We just don't have the, yeah, well, oh, that's.
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I mean, I got this in part, actually,
link |
because you were like, you know,
link |
last time I was here, he was like, look at the carpet.
link |
You know, if you had an alien detector
link |
where the carpet be aliens.
link |
I mean, I think we really don't.
link |
I think it would be.
link |
But the aliens would nevertheless have a high assembly index
link |
or produce things of high assembly index.
link |
And those things of high assembly index,
link |
you have to have a detector that can recognize
link |
high assembly index in all its forms.
link |
That's it, that's it.
link |
Take data, construct assembly space.
link |
Yeah. Those patterns, basically.
link |
So one way to think about high assembly index
link |
is interesting patterns of basic ingredients.
link |
I can give you an example,
link |
because I mean, in molecules,
link |
we've been talking about in objects,
link |
but we're also trying to do it in spatial trajectories.
link |
Like, imagine you're just,
link |
like, I always get bothered by the fact that, like,
link |
when you look at birds flocking,
link |
you can describe that with like a simple Boyd's model,
link |
or like, you know, people use spin glass
link |
to describe animal behavior.
link |
And those are like really simple physics models.
link |
Yet you're looking at a system that you know has agency
link |
and there's intelligence in those birds.
link |
And basically, like, you can't help but think
link |
there must be some statistical signatures
link |
of the fact that they're,
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that's a group of agents versus, you know, like,
link |
I don't know, you know, the physics example,
link |
maybe like, I don't know, Brownian motion or something.
link |
And so what we're trying to do
link |
is actually apply assembly to trajectory data
link |
to try to say there's a minimal amount of causal history
link |
to build up certain trajectories for observed agents
link |
that's like an agency detector for behavior.
link |
Do you think it's possible to do some like Boyd's
link |
or those kinds of things, like artificial,
link |
like cellular automata, play with those ideas
link |
with assembly, with assembly theory?
link |
Have you found any useful, really simple mathematical,
link |
like, simulation tools that allow you
link |
to play with these concepts?
link |
So like one, of course, you're doing mass spec
link |
in this physical space with chemistry,
link |
but it just seems, well, I mean,
link |
computer science person, maybe,
link |
it seems easier to just.
link |
It seems even sexier in terms of tweeting visual information
link |
on Twitter or Instagram, more importantly,
link |
to play like, here's an organism of a low assembly index
link |
and here's an organism of a high assembly index
link |
and let's watch them create more and more memories
link |
and more and more complex objects.
link |
And so like, in mathematics,
link |
you get to observe what that looks like
link |
to build up an intuition what assembly index is like.
link |
We are building a toolkit right now.
link |
So I think it's a really good idea,
link |
but what we've got to do is I'm kind of still obsessed
link |
with the infrastructure required.
link |
And one of the reasons why I was pushing on information
link |
and mathematics when human beings,
link |
when human beings, we take a lot of the infrastructure
link |
And I think we have to strip that back a bit
link |
for going forward, but you're absolutely right.
link |
I would agree that I think the fact that we exist
link |
in the universe, this is like,
link |
I can see that lots of people would disagree
link |
with the statement, but I don't think Sarah will,
link |
The fact that objects exist,
link |
I don't think anyone on earth will disagree
link |
that objects can exist elsewhere, right?
link |
But they will disagree that life can exist elsewhere.
link |
But what perhaps I'm trying to say is that
link |
the acquisition, the universe's ability to acquire memory
link |
is the very first step for building life.
link |
And that must be, that's so easy to happen.
link |
So therefore alien life is everywhere
link |
because all alien life is,
link |
is those memories being compressed and minimalized
link |
and the alien equivalent of the cell working.
link |
So I think that we will build new technologies
link |
to find aliens, but we need to understand what we are first
link |
and how we go from physics to chemistry to biology.
link |
The most interesting thing,
link |
as you're saying to these two organisms,
link |
different assemblies, there's one you get into biology.
link |
Biology gets more and more weird,
link |
more and more contingent.
link |
Physics is, chemistry is less weird
link |
cause the rules of chemistry are smaller
link |
than the rules of biology.
link |
And then going away to physics where you have a very
link |
nicely tangible number of ways of arranging things.
link |
And I think assembly theory just helps you appreciate that.
link |
And so once we get there,
link |
my dream is that we are just gonna be able to suddenly,
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I mean, I'm maybe just being really arrogant here.
link |
I don't mean to be arrogant.
link |
It's just, I've got this hammer called assembly
link |
and everything's a nail.
link |
But I think that once we crack it,
link |
we'll be able to use assembly theory plus telescopes
link |
Do you have, Sarah, do you have disagreements with Lee
link |
on the number of aliens that are out there?
link |
I do actually, yeah, well.
link |
And what they look like.
link |
So any of the things we've been talking about,
link |
is there nuanced, it's always nice to discover wisdom
link |
through nuanced disagreement.
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Yeah, I don't wholly disagree, but I think,
link |
but I do think I disagree.
link |
It's kind of, there's nuance there.
link |
It is nuanced, right?
link |
So you made the point earlier that you think,
link |
once we discover what life is,
link |
we'll see alien life everywhere.
link |
And I think I agree on some levels in the sense
link |
that I think the physics that governs us is universal.
link |
But I don't know how far I would go to say,
link |
to say that we're a likely phenomenon
link |
because we don't understand all of the features
link |
of the transition at the origin of life,
link |
which we would just say in assembly,
link |
as you go from the no memory physics
link |
to there's like a critical transition
link |
around the assembly index
link |
where assembliness starts to increase.
link |
And that's what we call the evolution of the biosphere
link |
and complexification of the biosphere.
link |
So there's a principle of increasing assembliness
link |
where that goes back to what I was saying
link |
at the very beginning about the physics of the possible,
link |
that the universe basically gets in this mode
link |
of trying to make as much possibilities as possible.
link |
Now, how often that transition happens
link |
that you get the kind of cascading effect
link |
that we get in our biosphere, I think we don't know.
link |
If we did, we would know the likelihood of life
link |
And a lot of people wanna say life is common,
link |
but I don't think that we can say that yet
link |
till we have the empirical data,
link |
which I think you would agree with.
link |
But then there's this other kind of thought experiment I have
link |
which I don't like, but I did have it,
link |
which is if life emerges on one planet
link |
and you get this real high density of things
link |
that can exist on that planet,
link |
is it sort of dominating the density of creation
link |
that the universe can actually generate?
link |
So like if you're thinking about counting entropy, right?
link |
Like the universe has a certain amount of stuff in it.
link |
And then assembly is kind of like an entropic principle.
link |
But the idea is that now transformations among stuff
link |
or the actual physical histories of things
link |
now become things that you have to count
link |
as far as saying that these things exist
link |
and we're increasing the number of things that exist.
link |
And if you think about that cosmologically,
link |
maybe Earth is sucking up all the life potential
link |
of the whole universe, I don't know.
link |
How's that, can you expand that a little bit?
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Why can any one geographical region
link |
suck up the creative capacity of the universe?
link |
Just like, I know it's a ridiculous thought.
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I don't actually agree with it,
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but it was just a thought experiment.
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I love that you can have thoughts
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that you don't like and don't agree with,
link |
but you have to think through them anyway.
link |
The human mind is fascinating.
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Yeah, I think these sort of counterfactual
link |
thought experiments are really good
link |
when you're trying to build new theories
link |
because you have to think through all the consequences.
link |
And there are people that want to try to account for,
link |
say, the degrees of freedom on our planet
link |
in cosmological inventories of talking about
link |
the entropy of the universe.
link |
And when we're thinking about cosmological
link |
arrow of time and things like that.
link |
Now, I think those are pretty superficial proposals
link |
as they stand now, but assembly would give you
link |
a way of counting it.
link |
And then the question is if there's a certain
link |
maximal capacity of the universe's speed
link |
of generating stuff, which Lee always has this argument
link |
that assembly is about time.
link |
The universe is generating more states.
link |
Really what it's generating is more assembly possibilities.
link |
And then dark energy might be one manifestation of that,
link |
that the universe is accelerating its expansion
link |
because that makes more physical space.
link |
And what's happening on our planet is it's accelerating
link |
in the expansion of possible things that exist.
link |
And maybe the universe just has a maximal rate
link |
of what it can do to generate things.
link |
And then if there is a maximal rate,
link |
maybe only a certain number of planets
link |
can actually do that.
link |
Or there's a trade off about the pace of growth
link |
on certain planets versus others.
link |
I have a million questions there,
link |
but do you have thoughts on?
link |
Just a quick, yeah, I'll just say something very quick.
link |
It's a thought experiment.
link |
No, it's good, I think I get it.
link |
So what I want to say is when I mean aliens are everywhere,
link |
I mean memories are the prerequisite
link |
for aliens via selection
link |
and then concentration of selection
link |
when selection becomes autonomous.
link |
So what I would love to do is to build,
link |
say a magical telescope that was a memory,
link |
a magical one, or a real one,
link |
that would be a memory detector to see selection.
link |
So you could get to exoplanets and say that exoplanet
link |
looks like there's lots of selection going on there.
link |
Maybe there's evolution and maybe there's going to be life.
link |
So what I'm trying to say is narrow down
link |
the regions of space where you say
link |
there's definitely evidence of memory as high assembly there
link |
or not high assembly, because that would be life,
link |
but where it's capable of happening.
link |
And then that would also help us frame the search for aliens.
link |
I don't know how likely it is to make the transition
link |
to cells and all the other things.
link |
I think you're right.
link |
But I think that we just need to get more data.
link |
Well, I didn't like the thought experiment
link |
because I don't like the idea
link |
that if the universe has a maximal limit
link |
on the amount it can generate per unit time
link |
that our existence is actually precluding the existence
link |
Well, I'll just say one thing.
link |
But I think that's probably true anyway
link |
because of the resource limitations.
link |
So I don't like your thought experiment
link |
because I think it's wrong.
link |
Well, no, no, I do like the thought experiment.
link |
So what you're trying to say is like,
link |
there is a chain of events that goes back
link |
that's manifestly culminated with life on Earth.
link |
And you're not saying that life isn't possible elsewhere.
link |
You say that there has been these number of things,
link |
contingent things that have happened
link |
that have allowed life to merge here.
link |
That doesn't mean that life can't emerge elsewhere,
link |
but you're saying that the intersection of events
link |
may be concentrated here, right?
link |
And I think there's...
link |
It's more like if you look at,
link |
say the causal graphs are fundamental,
link |
maybe space is an emergent property,
link |
which is consistent with some proposals on quantum gravity,
link |
but also how we talk about things in assembly theory.
link |
Then the universe is causal graphs generating
link |
more structure in causal graphs, right?
link |
So this is how the universe is unfolding.
link |
And maybe there's a cap on the rate of generation.
link |
Like there's only so much stuff
link |
that gets made per update of the universe.
link |
And then if there's a lot of stuff being made
link |
in a particular region that happens
link |
to look the same locally, spatially,
link |
that's an after effect of the fact
link |
that the whole causal graph is updating.
link |
Yeah, I don't know that.
link |
I think that that doesn't work.
link |
I don't think it works either,
link |
but I don't have a good argument in my mind about.
link |
But I do like the idea of the capacity that universe,
link |
cause you've got the number of states.
link |
Yeah, we can come back to it.
link |
Let me ask real quick.
link |
Like why does different like local pockets
link |
of the universe start remembering stuff?
link |
How does memory emerge exactly?
link |
So at the origin of the universe, it was very forgetful.
link |
That's when the physicists were happiest.
link |
It was low memory objects,
link |
which is like ultra low memory objects,
link |
which is what the definition of stuff.
link |
Okay, so how does memory emerge?
link |
How does the temporal stickiness of objects emerge?
link |
I'm gonna take a very chemocentric point of view
link |
because I can't imagine any other way of doing it.
link |
You could think of other ways maybe.
link |
But I would say heterogeneity in matter
link |
is where the memory...
link |
So you must have enough different ways
link |
of rearranging matter for there to be a memory.
link |
So what that means,
link |
if you've got particles colliding in a box,
link |
let's just take some elements in a box.
link |
Those elements can combine in a combinatorial set of ways.
link |
So there's a combinatorial explosion
link |
of the number of molecules or minerals or solid objects,
link |
Because there's such a large number,
link |
the population of different objects that are possible,
link |
this goes back to assembly theory
link |
where assembly theory, there's four types of universes.
link |
So you've got basically, and this is what one was up earlier
link |
where one universe where you've just got
link |
everything is possible.
link |
So you can take all the atoms
link |
and combine them and make everything.
link |
Then you've got basically what is the assembly combinatorial
link |
where you basically have to accrue information in steps.
link |
Then you've got assembly observed,
link |
and then you've got the object assembly going back.
link |
So what I'm trying to say is like,
link |
if you can take atoms and make bonds,
link |
let's say you take a nitrogen atom and add it
link |
to a carbon atom, you find an amino acid,
link |
then you add another carbon atom on
link |
in a particular configuration,
link |
then another one, all different molecules.
link |
They all represent different histories.
link |
So I would say for me right now,
link |
the most simple route into life seems to be
link |
through recording memories and chemistry.
link |
But that doesn't mean there can't be other ways
link |
and can't be other emergent effects.
link |
But I think if you can make bonds
link |
and lots of different bonds,
link |
and those molecules can have a causal effect on the future.
link |
So imagine a box of atoms,
link |
and then you combine those atoms in some way.
link |
So you make molecule A from load of atoms,
link |
and then molecule A can go back to the box
link |
and influence the box.
link |
Then you make A prime or AB or ABC.
link |
And that process keeps going,
link |
and that's where the memories come from,
link |
is that heterogeneity in the universe from bonding.
link |
I don't know if that makes any sense.
link |
And it's beginning to flourish at the chemistry level.
link |
So the physicists have no, like not enough.
link |
They're like desperately begging
link |
for more freedom and heterogeneous components to play with.
link |
Yeah, that's exactly it.
link |
What do you think about that, Sarah?
link |
I mentioned already, I think it's significant
link |
that whatever physics governs life
link |
emerges actually in chemistry.
link |
It's not relevant at the subatomic scale
link |
or even at the atomic scale.
link |
It's in, well, atomic scale because chemistry.
link |
But like when you get into this combinatorial diversity
link |
that you get from combining things on the periodic table,
link |
that's when selection actually matters
link |
or the fact that some things can exist
link |
and others can't exist actually starts to matter.
link |
So I think of it like you don't study gravity
link |
inside the atomic nucleus.
link |
You study it in terms of large scale structure
link |
of the universe or black holes or things like that.
link |
And whatever we're talking about as physics of information
link |
or physics of assembly becomes relevant
link |
at a certain scale of reality.
link |
And the transition that you're talking about,
link |
I would think of as just when you get a sufficient density
link |
in terms of the assembly space
link |
of like the relationship of the overlap
link |
and the assembly space,
link |
which is like a feature of common memory,
link |
there is this transition to assembly dominated physics,
link |
Oh, like when we're talking about,
link |
and we're trying to map out exactly
link |
what that transition looks like.
link |
We're pretty sure of some of its features,
link |
but we haven't done all of the...
link |
Do you think if you were there in the early universe,
link |
you would have been able to predict
link |
the emergence of chemistry and biology?
link |
And I ask that because at this stage as humans,
link |
do you think we can possibly predict the length of memory
link |
that might be able to be formed later on
link |
in this pocket of the universe?
link |
Like how complex is, what is the ceiling of assembly?
link |
I think as much time as you have in the past
link |
is how much you can predict in the future.
link |
Because it's actually physical in the system
link |
and you have to have enough time
link |
for features of that structure to exist.
link |
Wait, let me push back on that.
link |
Isn't there somewhere in the universe
link |
that's like a shortest path that's been,
link |
that stretches all the way to the beginning?
link |
That's building some giant monster?
link |
So you can't predict.
link |
The universe has as much memory
link |
as the largest assembly object in the universe.
link |
But so you can't predict.
link |
You can't predict any deeper than that, no.
link |
So like that, I guess what I'm saying is,
link |
like what intuition do you have about complexity
link |
living in the world that you'd have today?
link |
Right, because you just, you can,
link |
I mean I guess how long does it get more fun?
link |
Like isn't there gonna be at some point,
link |
because there's a heat death in the universe,
link |
isn't there going to be a point of the most,
link |
of the highest assembly of object,
link |
with the highest probability being generated?
link |
When is the universe gonna be the most fun,
link |
and can we freeze ourselves and then live then?
link |
And will you know when you're having the most fun
link |
that this is the best time, you're in your prime?
link |
Are you going to do what everyone does,
link |
which is deny that you're in your prime,
link |
and the best years are still ahead of you?
link |
What option do you have?
link |
I don't, I mean the problem is there's lots of,
link |
lots of really interesting features here.
link |
I just wanna mention one thing that might be,
link |
is I do think assembly theory applies all the way back
link |
to subatomic particles.
link |
And I also think that cosmological selection
link |
might've been actually, there might've been,
link |
I would say it's a really boring bit,
link |
but it's really important for a cosmologist
link |
that universes have gone through.
link |
Was it Lee Smolin who proposed this?
link |
Maybe that there is this,
link |
that basically a universe evolves,
link |
you've got the wrong constants, we'll start again.
link |
And the most productive constants
link |
where you can allow particles to form in a certain way,
link |
propagate to the next universe, and we go again.
link |
So actually selection goes all the way back,
link |
and there's this cycle of universes.
link |
And now this universe has been selected
link |
because life can occur, and it carries on.
link |
But I've really butchered that.
link |
There is a much more.
link |
So this is some aspect where through the selection process
link |
there's parameters that are being fine tuned,
link |
and we happen to be living in one
link |
where there's some level of fine tuning.
link |
Is there, given that, can you steel man the case
link |
that we humans are alone in the universe?
link |
We are the highest assembly index object in the universe.
link |
Yeah, I can, I guess.
link |
I mean, so from a.
link |
Yes, it's possible.
link |
I mean, it's possible.
link |
So let me, so okay, so there is a particular
link |
set of elements on Earth in a particular ratio,
link |
and the right gravitational constant,
link |
and the right viscosity, you know,
link |
of stuff being able to move around,
link |
the right distance from our sun,
link |
right number of events where we have a moon,
link |
the Earth is rotating.
link |
The late heavy bombardment produced a lot of,
link |
brought in the right stuff.
link |
And Mars was cooking up, you know,
link |
the right molecules first.
link |
So it was habitable before Earth.
link |
It was actually doing the combinatorial search.
link |
And before Mars kind of became uninhabitable,
link |
it seeded Earth with the right molecular replicators.
link |
And there was just the right stuff on Earth,
link |
and that's how the miracle of life occurred.
link |
Although I find I'm very uncomfortable with that
link |
because actually, because life came so quickly
link |
in the Earth's past.
link |
But that doesn't mean that life is easy elsewhere.
link |
It just might mean that,
link |
because chemistry is actually not a long term thing.
link |
Chemistry can happen quickly.
link |
So maybe going on with the steel manning of the argument
link |
to say actually, the fact that life emerged quickly
link |
doesn't mean that life is easy.
link |
It just means that the chemistry was right on Earth,
link |
and Earth is very special.
link |
And that's why there's no life
link |
anywhere else in the universe.
link |
Yeah, so Sarah mentioned this kind of cascading thing.
link |
So what if that's the reason we're lucky,
link |
is that we got to have a rare cascading of,
link |
like an accelerating cascading effect
link |
in terms of the complexity of things.
link |
So like, maybe most of the universe
link |
is trying to get sticky with the memory,
link |
and it's not able to really form it.
link |
And then we got really lucky in that.
link |
And it has nothing,
link |
like there's a lot of Earth like conditions, let's say,
link |
but it's just you really, really have to get lucky on this.
link |
But I'm doing experiments right now.
link |
In fact, experiments that Sarah and I are working on,
link |
because we have some joint funding for this,
link |
where we're seeing that the universe
link |
can get sticky really quickly.
link |
Now, of course, we're being very anthropocentric,
link |
we're using laboratory tools, we're using theory,
link |
but actually, the phenomena of selection,
link |
the process of developing heterogeneity,
link |
we can do in the lab.
link |
We're just seeing the very first hints of it.
link |
And wouldn't it be great if we can start to pin down
link |
a bit more precisely becoming good Bayesianists for this,
link |
for the origin of life and the emergence of life,
link |
to finding out what kind of chemistries
link |
we really need to look for.
link |
And I'm becoming increasingly confident
link |
we'll be able to do that in the next few years.
link |
Make life in the lab or make some selection in the lab
link |
from inorganic stuff, from sand, from rocks,
link |
from dead stuff, from moon.
link |
Wouldn't it be great to get stuff from the moon,
link |
put it in our origin of life experiment,
link |
and make moon life?
link |
And restrict ourselves to interesting self replicating
link |
stuff that we find on the moon.
link |
Sarah, what do you think about this approach
link |
of engineering life in order to understand life?
link |
So building life in the machine.
link |
Yeah, so, I mean, Lee and I are trying right now
link |
to build a vision for a large institute
link |
or experimental program, basically, to do this problem.
link |
But I think of it as like, we need to simulate a planet.
link |
So like the Large Hadron Collider was supposed
link |
to be simulating conditions just after the Big Bang.
link |
Lee's built a lot of technology in his lab
link |
to do these kind of selection engines.
link |
But the question you're asking is,
link |
how many experiments do you need to run?
link |
What volume of chemical space do you need to explore
link |
before you actually see an event?
link |
And I like to make an analogy
link |
to one of my favorite particle physics experiments,
link |
which is Super Kamiakande that's looking
link |
for the decay of the proton.
link |
So this is something that we predicted theoretically,
link |
but we've never observed in our universe.
link |
And basically what they're doing is every time
link |
they don't see a proton decay event,
link |
they have a longer bound on the lifetime of a proton.
link |
So imagine we built an experiment with the idea in mind
link |
of trying to simulate planetary conditions,
link |
physically simulate.
link |
You can't simulate origin life in a computer.
link |
You have to do it in an experiment.
link |
Simulate enough planetary conditions
link |
to explore the space of what's possible
link |
and bound the probability for an origin life event.
link |
Even if you're not observing it,
link |
you can talk about the probability.
link |
But we, hopefully, life is not exponentially rare
link |
and we would then be able to evolve
link |
in an automated system alien life in the lab.
link |
And if we can do that, then we understand the physics
link |
as well as we understand what we can do
link |
in particle accelerators.
link |
So keep expanding physically the simulation,
link |
the physical simulation, until something happens.
link |
Yeah, or just build a big enough volume
link |
of chemical experiments and evolve them.
link |
So if you say volume, you mean like literally volume?
link |
I mean physical volume in terms of space,
link |
but I actually mean volume in terms
link |
of the combinatorial space of chemistry.
link |
How do you nicely control the combinatorial exploration,
link |
the search space, such that it's always like
link |
you keep grabbing the low hanging fruit?
link |
Yeah, how do you build a search engine for chemistry?
link |
It's like for aliens. I think you explained it really well.
link |
We should carry on doing this.
link |
I should pretend the physics, be the physicist,
link |
you be the chemist.
link |
So the way to do it is I will always play a joke.
link |
Cause I like writing grants to ask for money
link |
But years ago I started wanting to build.
link |
So I actually wanted the weather.
link |
So I built this robot in my lab called the computer,
link |
which is this robot you can program to do chemistry.
link |
I made a programming language for the computer
link |
and made it operate chemical equipment.
link |
Originally I wrote grants to say,
link |
Hey, I want to make an origin of life system.
link |
And no one would give me any money for this.
link |
They said, what this is ridiculous.
link |
Why are you wanting to make, oh, it's really hard.
link |
You're not a very good origin of life chemist anyway.
link |
Why would we give you any money?
link |
And so I turned it around and said, can you,
link |
can instead, can you give me money to make robots,
link |
to make molecules are interesting.
link |
And everyone went, yeah, okay, you can do that.
link |
And that's, so actually the funny thing is the computer
link |
project, which I have in my lab, which is very briefly,
link |
it's just basically, it's like literally an automated
link |
And we've made a programming language for the test tube,
link |
which is cool, has come as literally came from this.
link |
I went to my lab one day.
link |
So I want to make a search engine to get origin of life
link |
because they don't have a planet.
link |
And I thought about doing in a microfluidic format.
link |
So microfluidic is very nano, very small channels
link |
in device where you can basically have all the pipes
link |
lit dump produced by lithography.
link |
And you can have a chamber, maybe say between say 10
link |
and a hundred microns in volume.
link |
And we slot them all together like Lego,
link |
and we can make an origin of life system.
link |
And I could never get it to work.
link |
And I realized I had to make, do chemistry at the kind of
link |
test tube level and what you want to be able to do.
link |
Yeah, it goes back to that tweet in 1981.
link |
1981, the computer, we're looking at a tweet from Lee.
link |
In 1981, the computer was a distant dream in,
link |
oh wow, this is the scientist looking back.
link |
It is the young boy who dreamed.
link |
In 2018, it was realized, spelled in a British way,
link |
realized, which is the wrong way.
link |
Yeah, I'm starting with Z, but not.
link |
So now there's a system that does the physical
link |
manifestation or whatever the programming language,
link |
the spec tells you to do.
link |
Yeah, well in 1981, I got my first computer, ZX81.
link |
What was the computer?
link |
It was, and I got a chemistry set.
link |
And I liked the chemistry set and I liked the computer
link |
and I just wanted to put them together.
link |
I thought, wouldn't it be cool if I could just use
link |
the computer to control the chemistry set.
link |
And obviously that was insane.
link |
And I was like, you know, eight years old, right?
link |
Nine years old, going on nine years old.
link |
And then I invented the computer
link |
just because I wanted to build this origin of life grid.
link |
Which is like literally a billion test tubes
link |
connected together in real time and real space,
link |
basically throwing a chemical dice.
link |
Throw dice, throw dice, throw dice.
link |
You're gonna get lucky.
link |
And that's what we, I think Sarah and I
link |
have been thinking very deeply about.
link |
Because, you know, there's more money being spent
link |
on the origin of the gravity
link |
or looking at the Higgs boson than the origin of life, right?
link |
And the origin of life is the, I think the biggest question
link |
or not the biggest question, it is a big question.
link |
Let's put it that way.
link |
It is the biggest question.
link |
You're okay saying that.
link |
Isn't it possible once you figure out the origin of life
link |
that that's not going to solve,
link |
that's not actually gonna solve
link |
the question of what is life?
link |
Because you're kind of putting a lot of.
link |
Yeah, I think they're the same problem.
link |
But you're putting, is it possible
link |
that you're putting too many,
link |
too much bets into this origin part?
link |
Maybe the origin thing isn't,
link |
isn't there always a turtle underneath the turtle?
link |
Isn't there a stack of turtles?
link |
Because then if you create it in the lab,
link |
maybe you need some other stuff.
link |
Well, let's not think about the origin.
link |
Like in the lab, there's still memory.
link |
So the experiment is already the product of evolution.
link |
Right, in some maybe really deep way,
link |
not an obvious way, in some very deep way.
link |
So maybe the haters are always going to be like,
link |
well, you have to reconstruct the fold.
link |
You have to build a new script.
link |
Fortunately for us, the haters are not aware
link |
Well, no, I know, I just.
link |
We're the one making that argument usually, but yeah.
link |
I just think that if we create life in the lab,
link |
it's not obvious that you'll get
link |
to the deep, deep understanding of necessarily,
link |
what is the line between life and non life?
link |
No, I think, so there's so much here.
link |
I'm just like playing devil.
link |
So much here, but let me play devil's advocate
link |
back in a previous conversation, right?
link |
And say, yeah, I will.
link |
Cellular automata.
link |
Cellular automata, these very, very simple things
link |
where you color squares black or white
link |
and implement rules and play them in time.
link |
And you can get these very, very complex patterns coming out.
link |
You know, there's nice rules.
link |
There are Turing complete rules and I would argue
link |
that cellular automata don't really exist on their own.
link |
They have to exist in a computing device.
link |
If that, well, that's computing devices,
link |
a piece of paper and abstraction,
link |
a mathematician drawing a grid or a framework.
link |
Now, so I would argue CAs are beautiful things,
link |
simple, going complex, but the complexity is all borrowed
link |
from the lithography, the numbers.
link |
Right, now let's take that same argument
link |
with the chemistry experiment origin of life.
link |
What you need to be able to do is go,
link |
and I'm inspired to do this,
link |
to go out and look for CAs occur in nature.
link |
You know, let's kind of, let's find some CAs
link |
that just emerge in our universe and.
link |
For people just, sorry to interrupt,
link |
for people just listening and in general,
link |
I think what we're looking at is a cellular automata
link |
where again, as Lee described,
link |
there is just binary black or white squares
link |
and they only have local information
link |
and they're born and they die.
link |
And you would think nothing interesting would emerge,
link |
but actually what we're looking at is something
link |
that I believe is called glider guns
link |
or a glider gun, which is moving objects
link |
in this multi cell space that look like they're organisms
link |
that have much more information,
link |
that have much more complexity
link |
than the individual building components.
link |
In fact, look like they have a long term memory
link |
while the individual components don't seem like
link |
they have any memory at all, which is fascinating.
link |
The argument here is that has to exist
link |
on all this layer of infrastructure, right?
link |
And though it looks simple.
link |
And then what I would make, the argument I would make
link |
if I were you, say, well, I think CAs are really simple
link |
and everywhere, is say, show me how they emerge
link |
Now this goes to the origin of life, machine.
link |
I don't think we want to do the origin of life,
link |
just any origin is good.
link |
So we do, so we literally have our sand shaker,
link |
shake the sand like massive grid of chemistry experiments,
link |
shaking sand, shaking whatever.
link |
And then because we know what we've put in,
link |
so we know how we've cheated and the same way with CA,
link |
we know how we've cheated,
link |
we know the number of operations needed,
link |
we know how big a grid we want to get this.
link |
If we could then say, okay,
link |
how can we generate this recipe in the lab
link |
and make a life form?
link |
What contingency did we need to put in?
link |
And we're upfront about how we cheated, okay?
link |
Say, oh, you had to shake it, it was a periodic,
link |
planet rotates, it's tried, comes in and out.
link |
So, and then we can start to basically say,
link |
okay, how difficult is it for these features to be found?
link |
And then we can look for extra planets and other features.
link |
So I think Sarah is absolutely right.
link |
We want to explain to people we're cheating.
link |
In fact, we have to cheat.
link |
No one has given, I'm good at writing grants,
link |
well, I used to be, I'm not very good right now,
link |
I keep getting rejected,
link |
but writing a grant for a planet in 100 million years,
link |
no grant fund there is going to give me that,
link |
but maybe money to make a kind of a grid,
link |
a computer grid, origin of life computer grid.
link |
In physical space.
link |
In physical space, and just do it.
link |
So Sarah said something which is,
link |
you can't simulate the origin of life in a computer,
link |
so like in simulation, why not?
link |
What are your, you said it very confidently,
link |
so is it possible and why would it be very difficult?
link |
Like what's your intuition there?
link |
I think it's very difficult right now
link |
because we don't know the physics,
link |
but if you go based on principles of assembly theory
link |
and you think every molecule is actually
link |
a very large causal graph, not just the molecule,
link |
then you have to simulate all the features
link |
of those causal graphs,
link |
and I think it becomes computationally intractable.
link |
You might as well just build the experiment.
link |
Because you have, in the physical space,
link |
you have all the objects with all the memories.
link |
In the computer, you would have to copy them
link |
or reconstruct them.
link |
Yeah, that's a beautifully put,
link |
and I would say that lots of people,
link |
you just don't have enough resources.
link |
It's easier to actually do the physical experiment
link |
because we are literally,
link |
I would view the physical experiment
link |
almost like a computational experiment.
link |
We're just outsourcing, it's just basically,
link |
we're just outsourcing all the matrix algebra.
link |
And on your point about the experiment
link |
being also an example of life,
link |
it's almost like you want to design,
link |
it's like all of us are lineages
link |
of propagating information across time,
link |
and so everything we do becomes part of life
link |
because it's part of that causal chain.
link |
So it's like you want to try to pinch off
link |
as much as you can of the information
link |
from your causal chain that goes into the experiment,
link |
but you can't pinch off all of it
link |
to move it to a different timeline.
link |
It's always going to be part of your timeline.
link |
But at least if you can control
link |
how much information you put in,
link |
you can try to see how much does that particular trajectory
link |
you've set up start generating its own assembly.
link |
So you know where it starts,
link |
and then you want to try to see it take off on its own
link |
when you try to pinch it off as much as possible.
link |
Quick pause, bathroom break.
link |
And now we're back.
link |
We talked about the early days of the universe
link |
when there was just stuff and no memory,
link |
not even causality.
link |
I think Lee at least implied
link |
that causality is immersion somehow.
link |
We could discuss this.
link |
What happened before this all originated?
link |
What's outside the universe?
link |
Okay, so it's not relevant, not understandable.
link |
Is it useful to even ask the question?
link |
Just because it's so hard?
link |
No, it's not hard.
link |
It's just not a question.
link |
If I can't do an experiment or even think of an experiment,
link |
the question doesn't exist.
link |
Well, no, you can't think of a lot of experiments,
link |
What I mean is I can't.
link |
Your causality graph is like,
link |
this is what we're talking about.
link |
It's like there is limits to your ability
link |
to construct experiments.
link |
I agree, but I was trying to be facetious
link |
and I'm trying to make a point
link |
because I think that if there is a causal bottleneck
link |
through which information can't propagate in principle,
link |
then it's very hard to think of an experiment,
link |
even in principle, even one that's beyond
link |
my mediocre intellect, right?
link |
I'm happy to accept that.
link |
But this is one of the things I actually do think
link |
there was something before the Big Bang
link |
because I would say that I think the Big Bang
link |
just couldn't occur and create time.
link |
Time created the Big Bang.
link |
So there was time before the Big Bang.
link |
There was no space, but there was time.
link |
But I mean, I'm just making that stuff up
link |
just to make all the physicists happy,
link |
but I think it's...
link |
Do you think that would make them happy
link |
because they would be quite upset, actually.
link |
And why would they be upset?
link |
Because they would say that time can't exist
link |
before the Big Bang.
link |
Yeah, I mean, this goes back to an argument
link |
that you might not want to have the argument here.
link |
I was talking to Sarah earlier today
link |
about an argument we had about time a long time ago.
link |
A long time in time.
link |
And what I would, it's like, I think there is this thing
link |
called time or state creation.
link |
The universe is creating states and it's outside of space,
link |
but they create space.
link |
So what I mean is you can imagine there are states
link |
being created all the time.
link |
And there is this thing called time.
link |
Time is a clock, which you can use to measure
link |
when things happen, but that doesn't mean,
link |
because you can't measure something,
link |
that states aren't being created.
link |
And so you might locally refer to the Big Bang
link |
and the Big Bang occurred at some point
link |
when those states were there.
link |
Probably there had to be enough states
link |
for the Big Bang to occur.
link |
And then, but I think that there is something wrong
link |
with our conception of how the universe was created
link |
and the Big Bang because we don't really get time.
link |
Because again, I don't want to become boring
link |
and sound like a broken record, but time is a real thing.
link |
And until I can really explain that more elegantly,
link |
I'm just gonna get into more trouble.
link |
Well, we're gonna talk about time
link |
because time is a useful measuring device for experiments,
link |
but also time is an ideal, okay.
link |
But let me first ask Sarah, what do you think?
link |
Is it a useful question to ask what happened
link |
before the Big Bang?
link |
Is it a useful question to ask what's outside the universe?
link |
So I would think about it as the Big Bang
link |
is an event that we reconstructed
link |
as probably happening in the past of our universe
link |
based on current observational data.
link |
And so the way I like to think about it
link |
is we exist locally in something called the universe.
link |
So, and going back to like the physics of existence,
link |
we exist locally in the space of all things that could exist
link |
and we can infer certain properties of the structure
link |
of where we exist locally.
link |
And one of the properties that we've inferred in the past
link |
is that there is a thing we call the Big Bang.
link |
There's some signatures of our local environment
link |
that indicate that there was a very low information event
link |
that started our universe.
link |
I think that's actually just an artifact
link |
of the structure of the assembly space
link |
that when you start losing all the memory in the objects,
link |
it looks like what we call a Big Bang.
link |
So I think it makes sense to talk about
link |
where you are locally.
link |
I think it makes sense to talk about
link |
counterfactual possibilities,
link |
what could exist outside the universe
link |
in the sense that they become part of our reasoning
link |
and therefore part of our causal chain
link |
of things that we can do.
link |
So like the multiverse in my mind exists,
link |
but it doesn't exist as a multiverse
link |
of possible universes.
link |
It exists as an idea in our minds
link |
that allows us to reason about how physics works
link |
and then to do physics differently
link |
because we reason about it that way.
link |
So I always like to recenter it on things exist,
link |
but they don't always exist like we think they exist.
link |
So when we're thinking about things outside the universe,
link |
they absolutely exist because we're thinking about them,
link |
but they don't look like the projections in our minds.
link |
They're something else.
link |
And something you said just gave an idea
link |
to go back to your question.
link |
If there was, I mean, if something caused the Big Bang,
link |
if there was some memory or some artifact of that,
link |
then of course, to answer your question,
link |
it's worth going back to that
link |
because that would imply there is something
link |
beyond that barrier, that filter.
link |
And that's what you were saying, I guess, right?
link |
I'm agnostic to what exists outside the universe.
link |
I just don't think that.
link |
I think the most interesting things for us to be doing
link |
are finding explanations that allow us to do more,
link |
like that optimism.
link |
So I tend to draw the boundary on questions I ask
link |
as being scientific ones because I find
link |
that that's where the most creative potential is
link |
to impact the future trajectory
link |
of what we're doing on this planet.
link |
It's an interesting thing about the Big Bang
link |
is basically from our current perspective
link |
of what we're able to detect,
link |
it's the time when things were forgotten.
link |
It's the time to reset from our limited perspective.
link |
And so the question is, is it useful to ever study
link |
the thing that was forgotten?
link |
Or should we focus just on the memories
link |
that are still there?
link |
Well, the point I was trying to make about the experiment
link |
is I was trying to say both things.
link |
And I think perhaps yes, from the portfolio point of view,
link |
if you could then imagine what was forgotten
link |
and then work forwards,
link |
you will have different consequences.
link |
So then it becomes testable.
link |
So as long as we can find tests,
link |
then it's definitely worth thinking about.
link |
What I don't like is when physicists say
link |
what happened before the Big Bang
link |
and before, before, before,
link |
without giving me any credible conjecture
link |
about how would we know the difference?
link |
But the way you framed it is quite nice.
link |
It's like, what have we forgotten?
link |
Is there room for God in assembly theory?
link |
I like arguments for a necessary being better than God.
link |
Well, I think I said it earlier.
link |
What's a necessary being?
link |
What's a necessary?
link |
Like something that has to exist.
link |
Oh, so you like, I mean, you like the shortest path.
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Like does God need?
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I mean, well, you can go back to like Thomas Aquinas
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and arguments for the existence of God.
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But I think most of the interesting theological arguments
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are always about whether something has to exist
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or there was a first thing that had to exist.
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But I think there's a lot of logical loopholes
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in those kind of arguments.
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Well, so God here, meaning the machine
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that creates, that generates the stuff.
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But God, so what I was trying to say earlier is that.
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Isn't that just the universe though?
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Well, yeah, well, but there's a difference between,
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I sort of imagine like a black box, like a machine.
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I mean, I would be more comfortable calling that God
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because it's a machine.
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You go into a room and there's a thing with a button.
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Yeah, I don't like the great programmer in the sky version.
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Yeah, but if it's more kind of like,
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I don't like to think of, if you look at a cellular automata,
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if it's the cells and the rules,
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that doesn't feel like God
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that generates a bunch of stuff.
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But if there's a machine like that does,
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that runs the cellular automata and set the rules,
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then that feels like God.
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That sort of, in terms of terminology.
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So I wonder if there's like a machine
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that's required to generate this universe.
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That's very sort of important for running this in the lab.
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So as I said earlier, I think I said this earlier,
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that I can't remember the phrase, but something like,
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I mean, does God exist in our universe?
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Where does God exist?
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God at least exists in abstraction in our minds,
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particularly of people who have religious faith
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But let's then take, but you're talking a little bit more
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about generics, say, well,
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is there a mechanism beyond the universe you're calling God?
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I would say God did not exist at the beginning,
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but he or she does now.
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Because I'm saying the mechanism.
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Well, you don't know that he didn't exist in the beginning.
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So like this could be us in our minds trying to,
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like just listening to gravitational waves,
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detecting gravitational waves.
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It's the same thing.
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It's us trying to go back further and further
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into our memories to try to understand the machines
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that make up, that make up us.
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And so it's possible that we're trying to grasp
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at possible kind of what kind of machines could create.
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There's always a tweet.
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There's always a tweet.
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If the universe is a computer, then God must have built it
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because computers need creators.
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And then Joshe Bach replied,
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since there's something rather than nothing,
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perhaps existence is the default.
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If existence is the default, then many computers exist.
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Creator gods are necessary computers,
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unnecessarily computers too.
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I'm very confused by that, but that's an interesting idea
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that existence is the default versus nonexistence.
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I agree with that, but the rest is not.
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And then Lee responds,
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perhaps this reasoning is incomplete.
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That's how scientists talk trash each other
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on Twitter apparently.
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Which part don't you agree with?
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When he said if existence is default,
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then many computers exist,
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this comes back to the inventor and discovery argument.
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I would say the universe at the beginning wasn't capable
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of computation because there wasn't enough technology,
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So what you're saying is if God is a mechanism,
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so I might actually agree,
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but then the thing is lots of people see God
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as more than a mechanism.
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For me, God could be the causal graph in assembly theory
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that creates all the stuff that the memories we know.
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And the fact that we can even relate to each other
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is because we have the same, we share that heritage.
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And why we love each other
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or we like to see God in each other
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is it's just we know we have a shared existence.
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So if the God is the mechanism
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that created this whole thing,
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I think a lot of people see God in a religious sense
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as that mechanism also being able to communicate
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with the objects it creates.
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And if it's just the mechanism,
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we won't be able to communicate with the objects it creates.
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It can only create.
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You can't interact with the...
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Well, there's versions of God that create the universe
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For some religions.
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The first spark, yeah.
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But I think I liked your analogy
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of the machine and the rules, right?
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But I think part of the problem is,
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I mean, we have this conception
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that we can disentangle the rules
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from the physical substrate, right?
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And that's the whole thing about software and hardware
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being separate or the way Newton wrote his laws
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that there was some,
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like they exist outside the universe.
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They're not actually a feature of the universe.
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They don't have to emerge out of the universe itself.
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So I think if you merge your two views,
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then it gets back to the God is the universe.
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And then I think the deeper question
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is why does it seem like there's meaning and purpose?
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And if I think about the features of the universe
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that give it the most meaning and purpose,
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those are what we would call
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the living components of the universe.
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So if you wanted to say God is a physically real thing,
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which you were saying
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is like an emergent property of our minds,
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but I would just say the way the universe
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creates meaning and purpose,
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there is really a physics there.
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It's not like a illusory thing.
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And that is just what the physics of life is.
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Is it possible that we've forgotten
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much of the mechanisms that created the universe?
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So like, so basically, you know,
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whatever, if God is that mechanism,
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we just leave parts of that behind.
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Well, but the universe is constantly generating itself.
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So if God is that mechanism,
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it would be that that would still be active today.
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I don't, like, I'm agnostic,
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but if I recall the things I believe in God
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in the way that some people talk about God,
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I would say that God is, you know,
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like in the universe now, it's not an absent thing.
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So I think there's a mislabeling here
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because you're, I mean, I mean, I'm a professional idiot,
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actually, but, but, um.
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You should put that on your CV.
link |
Professionally, not recreationally or amateur,
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but professionally, you're paid for it.
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I would say if you were talking about God,
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I mean, again, I'm way out, way out of my depth here,
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and I almost feel uncomfortable.
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Yeah, but I feel quite uncomfortable articulating,
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For me, a lot of people that think of God as a consciousness
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and a reasoning entity that actually has causal power,
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and you're, and so you're, it's like,
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then you're saying like gravity could be God
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or time could be God.
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I mean, I think for me, for my conception of time
link |
is probably as fundamental as God
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because it gave rise to human intelligence and consciousness
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in which we can have this abstract notion of God.
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So I think that you're maybe talking about God
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in a very mechanistic, kind of unsophisticated sense,
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whereas other people say that God is more sophisticated
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and got all this, you know, feelings and love
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and, you know, and this abstracting ability.
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So is that what, or do you mean that?
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Do you mean God as in this conscious entity
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that decided to flick the universe into existence?
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Well, one of the features that God would have
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is the ability to flick the universe into existence.
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I, you know, like Windows 95,
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I don't know if God is Windows 95 or Windows XP
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or Windows 10, I don't know the full feature set.
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So at the very least, you have to flick the universe
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into existence, and then other features might include
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ability to interact with that universe in interesting ways,
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and then how do you interact with the universe
link |
in interesting ways?
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You have to be able to speak the language
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of its different components.
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So in order to interact with humans,
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you have to know how to act humanlike.
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So I don't know, but it seems like
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whatever mechanism created the universe
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might want to also generate local pockets of mechanisms
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that can interact with that.
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Like God was lonely?
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Yeah, I mean, it could be just a teenager
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and another just playing a video game.
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Well, I was gonna say, I mean, I don't,
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so this is referring to our origin of life engine.
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It's like, I don't believe in God,
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but that doesn't mean I don't wanna be one.
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I don't wanna make a universe and make a life form,
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but that may be rude to people who have
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dear religious beliefs.
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What I mean by that is if we are able to create
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an entirely new life form, different chemistry,
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different culture, what does it make us?
link |
By that definition, it makes us gods, right?
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I mean, like when you have children,
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you're like one of the magical things of that
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is you're kind of mini gods.
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I mean, first of all, from a child's perspective,
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parents are gods for quite a while.
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And then, I mean, in the positive sense,
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there's a magic to that.
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That's why I love robotics,
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is you instill life into something,
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and that makes you feel godlike in a sort of positive way.
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Being a creator is a positive feeling.
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Creator, yeah, exactly, on a small scale.
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And then God would be a creator
link |
at the largest possible scale, I suppose.
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Okay, you mentioned offline the Assembletron.
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What's an Assembletron?
link |
This is an early idea of something you're thinking about.
link |
So Sarah's team, well, I think Sarah's team
link |
are interested in using AI to understand life.
link |
My team is, and I'm wondering if we could apply
link |
the principles of assembly theory,
link |
that is the causal structure that you get
link |
with assembly theory, and hybridize it,
link |
and make a new type of neuron, if you like.
link |
I mean, there are causal neural networks out there,
link |
but they are not quite the architecture
link |
of what I would like.
link |
I would like to associate memory bits with,
link |
basically, I'd like to make a,
link |
rather than having an ASIC for neural networks,
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I wanna make an ASIC for assembly networks, right?
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So can you say that again?
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Assembly networks.
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So what is a thing with an input and an output,
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and it's like a neural network type of thing,
link |
what does it do exactly?
link |
What's the input, what's the output?
link |
So in this case, so if you're talking about
link |
a general neural network, I mean,
link |
in general neural network, you can train it
link |
on any sort of data, right, depending on the framework,
link |
whether it's like text, or image data, or whatnot.
link |
And that's fine, but there's no causal structure
link |
associated with that data.