back to indexSara Walker: The Origin of Life on Earth and Alien Worlds | Lex Fridman Podcast #198
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The following is a conversation with Sarah Walker,
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an astrobiologist and theoretical physicist
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at Arizona State University and the Santa Fe Institute.
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She's interested in the origin of life,
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how to find life on other worlds,
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and in general, the more fundamental question
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of what even life is.
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She seeks to discover the universal laws
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that describe living systems on Earth and elsewhere
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using physics, biology, and computation.
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Quick mention of our sponsors, Athletic Greens,
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NetSuite, Blinkist, and Magic Spoon.
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Check them out in the description to support this podcast.
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As a side note, let me say that my hope for this podcast
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is to try and alternate between technical
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and nontechnical discussions,
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to jump from the big picture
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down to specific detailed research
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and back to the big picture,
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and to do so with scientists and non scientists.
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Long term, I hope to alternate between discussions
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of cutting edge research in AI, physics, biology,
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to topics of music, sport, and history,
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and then back to AI.
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I hope you come along with me
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for that wild, oscillating journey.
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Some people message me saying to slow down
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since they're falling behind
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on the episodes of this podcast.
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To their disappointment, I have to say
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that I'll probably do more episodes, not less,
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but you really don't need to listen to every episode.
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Just listen to the ones that spark your curiosity.
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Think about it like a party full of strangers.
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You don't have to talk to everyone.
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Just walk over to the ones who look interesting
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and get to know them.
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And if you're lucky, that one conversation with a stranger
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might change the direction of your life.
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And it's a short life, so be picky with the strangers
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you talk to at this metaphorical party.
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This is the Lex Friedman podcast,
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and here is my conversation with Sarah Walker.
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How did life originate on Earth?
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What are the various hypotheses
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for how life originated on Earth?
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Yeah, so I guess you're asking a historical question,
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which is always a good place to start thinking about life.
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So there's a lot of ideas about how life started on Earth.
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Probably the most popular
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is what's called the RNA world scenario.
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So this idea is probably the one
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that you'll see most reported in the news.
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And is based on the idea that there are molecules
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in our bodies that relay genetic information.
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And we know those as DNA, obviously,
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but there's also a sort of an intermediary called RNA,
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ribonucleic acid, that also plays the role of proteins.
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And people came up with this idea in the 80s
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that maybe that was the first genetic material
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because it could play both roles of being genetic
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and performing catalysis.
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And then somehow that idea got reduced to this idea
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that there was a molecule that emerged on early Earth
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and underwent Darwinian evolution,
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and that was the start of life.
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So there's a lot of assumptions packed in there
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that we could unpack,
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but that's sort of the leading hypothesis.
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There's also other ideas about life starting as metabolism.
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And so that's more connected
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to the geochemistry of early Earth.
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And it would be kind of more focused on this idea
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that you get some kind of catalytic cycle of molecules
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that can reproduce themselves
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and form some kind of metabolism.
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And then life starts basically a self organization.
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And then you have to explain how evolution comes later.
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Right, so that's the difference
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between sort of energy and genetic code.
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So like energy and information
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are those are the two kind of things there?
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Yeah, I think that's a good way of putting it.
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It's kind of funny,
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because I think most of the people that think about
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these things are really disciplinary bias.
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So the people that tend to think about genetics
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come from a biology background
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and they're really evolution focused.
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And so they're worried about
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where does the information come from?
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And how does it change over time?
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But they're talking about information in a really narrow way
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where they're talking about a genetic sequence.
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And then most of the people that think about metabolism,
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origins of life scenarios tend to be
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people like physicists or geochemists
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that are worried about what are the energy sources
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and what kinds of organization
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can you get out of those energy sources?
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Okay, so which one is your favorite?
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I don't like either.
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Okay, all right, can we talk about them
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for a little bit longer though?
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Yeah, no, that's fine.
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So okay, so there's early Earth.
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What was that like?
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Was there just mostly covered by oceans?
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Was there heat sources, energy sources?
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So if we talk about the metabolism view
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of the origin of life,
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like where was the source of energy?
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Probably the most popular view
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for where the origin of life happened on Earth
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is hydrothermal vents because they had sufficient energy.
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And so we don't really know a lot about early Earth.
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We have some ideas about when oceans first formed
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and things like that,
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but the time of the origin of life
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is kind of not well understood or pinned down
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and the conditions on Earth at that time are not well known.
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But a lot of people do think
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that there was probably hydrothermal vents
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which are really hot, chemically active regions,
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say on the seafloor in modern times,
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which also would have been present on early Earth.
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And they would have provided energy and organics
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and basically all of the right conditions
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for the origins of life,
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which is one of the reasons
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that we look for these hydrothermal systems
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when we're talking about life elsewhere too.
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Okay, and for the genetic code,
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the idea is that the RNA is the first,
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like why would RNA be the first moment you can say it's life?
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I guess the idea is it could both
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have persistent information
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and then it can also do some of the work
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of like what, creating a self sustaining organism?
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Yeah, that's the basic idea.
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So the idea is you have, in an RNA molecule,
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you have a sequence of characters, say,
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so you can treat it like a string in a computer
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and it can be copied.
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So information can be propagated,
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which is important for evolution
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because evolution happens
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by having inheritance of information.
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So for example, like my eyes are brown
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because my mother's eyes were brown.
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So you need that copying of information,
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but then you also have the ability to perform catalysis,
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which means that that RNA molecule
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is not inert in that environment,
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but it actually interacts with something
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and could potentially mediate, say, a metabolism
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that could then fuel the actual reproduction
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So in some ways, people think that RNA gives you
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the most bang for your buck in a single molecule
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and therefore, it gives you all the features
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that you might think are life.
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And so this is sort of where this RNA world conjecture
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came from is because of those two properties.
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Isn't it amazing that RNA came to be in general?
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Isn't it? Yes, that is amazing.
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Okay, so we're not talking down about RNA.
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No, no, I love RNA.
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It's one of my favorite molecules.
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I think it's beautiful. It's just not step one.
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Yeah, I think the issue,
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it's not even the RNA world is a problem
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and actually, if you really dig into it,
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the RNA world is not one hypothesis.
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It is a set of hypothesis, hypotheses, sorry.
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And they range from a molecule of RNA spontaneously emerged
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on the early Earth and started evolving,
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which is kind of like the hardest RNA world scenario,
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which is the one I cited and I get a little animated about
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because it seems so blatantly wrong to me,
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but that's a separate story.
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And then the other one is actually something I agree with,
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which is that you can say there was an RNA world
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because RNA was the first genetic material
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for life on Earth.
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So an RNA world could just be the earliest organisms
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that had genetics in a modern sense,
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didn't have DNA evolved yet, they had RNA, right?
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And so that's sort of a softer RNA world scenario
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in the sense that it doesn't mean it was the first thing
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that happened, but it was a thing that definitely was part
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of the lineage of events that led to us.
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So if a life was like a best of album,
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it would be on the, it'd be one of the songs on there.
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Yes. One of the early songs.
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It's on the greatest hits.
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Greatest hits, that's the word I was looking for.
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Did life, do you think, originate once, twice,
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three times on Earth, multiple times?
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What do you think?
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I think that's a really difficult question.
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Is it an important question?
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It's a super important question.
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No, it's a really important question.
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And so there's a lot of questions in that question.
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So one of the first ones that I think needs to be addressed
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is is the origin of life a continuous process
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So we think about the origin of life as something
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that happened on Earth, say almost 4 billion years ago,
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because we have evidence of life emerging very early
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And then an origin of life event, quote unquote,
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a singular event, whatever that was, happened.
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And then all life on Earth that we know is a descendant
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of that particular event in our universe, right?
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And so, but we don't have any idea one way or the other
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if the origin of life is happening repeatedly,
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and maybe it's just not taking off
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because life is already established.
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That's a argument that people will make,
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or maybe there are alternative forms of life on Earth
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that we don't even recognize.
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So this is the idea of a shadow biosphere
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that there actually might just be
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completely other life on Earth,
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but it's so alien that we don't even know what it is.
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I'm gonna have to talk to you about the shadow biosphere.
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Yeah, that's a fun one.
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In a second, but first, let me ask for the other alternative,
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which is panspermia.
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So that's the idea, the hypothesis that life exists
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elsewhere in the universe and got to us
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through like an asteroid or a planetoid
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or some, according to Wikipedia, space dust,
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whatever the heck that is.
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But basically, it rode along whatever kind of rock
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Do you think that's at all a possibility?
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So I think the reason that most original life scientists
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are interested in the original life on Earth
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and say not the original life on Mars
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and then panspermia,
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the exchange of life between planets being the explanation
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is once you start removing the original life from Earth,
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you know even less about it
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than you do if you study it on Earth.
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Although, I think there are ways
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of reformulating the problem.
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This is why I said earlier,
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oh, you mean the historical original life problem.
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You don't mean the problem of how does life arise
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in the universe and what the universal principles are
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because there's this historic problem,
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how did it happen on early Earth?
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And there's a more tractable general problem
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of how does it happen?
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And how does it happen is something we can actually ask
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How did it happen on early Earth
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is a much more detailed and nuanced question
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and requires detailed knowledge of what was happening
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on early Earth that we don't have.
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And I'm personally more interested in general mechanisms.
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So to me, it doesn't matter if it happened on Earth
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or it happened on Mars.
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It just matters that it happened.
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We have evidence it happened.
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The question is, did it happen more than once
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And so the reason I don't find panspermia
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as a particularly,
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I think it's a fascinating hypothesis.
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I definitely think it's possible.
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And I in particular think it's possible
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once you get to the stage of life where you have technology
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because then you obviously can spread out
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But it's also possible for microbes
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because we know that certain microorganisms
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can survive the journey in space.
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And they can live in a rock and go between Mars and Earth.
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Like people have done experiments
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to try to prove that could work.
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So in that scenario, it's super cool
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because then you get planetary exchange,
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but say we go look for life on Mars
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and it ends up being exactly the same life we have on Earth,
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biochemically speaking,
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then we haven't really discovered something new
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about the universe.
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What kind of aliens are possible
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were there other origin of life events?
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If we find, if all the life we ever find
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is the same origin of life event in the universe,
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it doesn't help me solve my problem.
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But it's possible that that would be a sign
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that you could separate the environment
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from the basic ingredients.
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So you can have like a life gun
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that you shoot throughout the universe.
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And then like once you shoot it,
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it's like the Simpsons with a makeup gun.
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That was a great episode.
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When you shoot this life gun,
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it'll find the Earth's, it'll like get sticky.
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It'll stick to the Earth's.
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And that kind of reduces the barrier
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of like the time it takes,
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the luck it takes to actually,
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from nothing, from the basic chemistry,
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from the basic physics of the universe
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for the life to spring up.
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Yeah, I think this is actually super important
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to just think about,
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like does life getting seated on a planet
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have to be geochemically compatible with that planet?
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So you're suggesting like we could just shoot guns in space
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and like life could go to Mars
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and then it would just live there and be happy there.
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But that's actually an open question.
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So one of the things I was gonna say in response
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to your question about whether the origin of life
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happened once or multiple times,
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is for me personally right now in my thinking,
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although this changes on a weekly basis,
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but is that I think of life more as a planetary phenomenon.
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So I think the origin of life
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because life is so intimately tied to planetary cycles
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and planetary processes,
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and this goes all the way back
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through the history of our planet,
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that the origin of life itself grew out of geochemistry
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and became coupled and controlled geochemistry.
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And when we start to talk about life existing on the planet
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is when we have evidence of life
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actually influencing properties of the planet.
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And so if life is a planetary property,
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then going to Mars is not a trivial thing
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because you basically have to make Mars more Earth like.
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And so in some sense,
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like when I think about sort of longterm vision
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of humans in space, for example,
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really what you're talking about when you're saying,
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let's send our civilization to Mars
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is you're not saying let's send our civilization to Mars,
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you're saying let's reproduce our planet on Mars.
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Like the information from our planet
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actually has to go to Mars and make Mars more Earth like,
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which means that you're now having a reproduction process,
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like a cell reproduces itself
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to propagate information in the future.
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Planets have to figure out how to reproduce their conditions,
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including geochemical conditions on other planets
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in order to actually reproduce life in the universe,
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which is kind of a little bit radical,
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but I think for longterm sustainability
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of life on a planet, that's absolutely essential.
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Okay, so if we were to think about life
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as a planetary phenomena,
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and so life on Mars would be best
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if it's way different than life on Earth,
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we have to ask the very basic question
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I actually don't think that's the right question to ask.
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It took me a long time to get there, right?
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So I... Cross it out.
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Yeah, cross it off your list, it's wrong.
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No, no, no, I mean, I think it has an answer,
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but I think the part of the problem is,
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you know, most of the places in science
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where we get really stuck
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is because we don't know what questions to ask.
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And so you can't answer a question
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if you're asking the wrong question.
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And I think the way I think about it
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is obviously I'm interested in what life is.
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So I'm being a little cheeky when I say
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that's the wrong question to ask.
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That's exactly like the question
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that's like the core of my existence.
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But I think the way of framing that
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is what is it about our universe
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that allows features that we associate life to be there?
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And so really what I guess when I'm asking that question,
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what I'm after is an explanatory framework
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for what life is, right?
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And so most people, they try to go in and define life
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and they say, well, life is say,
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a self reproducing chemical system
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capable of Darwinian evolution.
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That's a very popular definition for life.
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Or life is something that metabolizes and eats.
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That is not how I think about life.
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What I think about life is there are principles
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and laws that govern our universe
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that we don't understand yet,
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that have something to do with how information interacts
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with the physical world.
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I don't know exactly what I mean even when I say that,
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because we don't know these rules,
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but it's a little bit like, I like to use analogies.
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You give me time to be like a little long winded
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for a second, even in as I,
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but sort of like if you look at the history of physics,
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for example, this is like,
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so we are in the period of the development of thought
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on our planet where we don't understand what we are yet.
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There was a period of thought in the history of our planet
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where we didn't understand what gravity was.
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And we didn't understand, for example,
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that planets in the heavens were actually planets
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or that they operated by the same laws that we did.
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And so there has been this sort of progression
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of getting a deeper understanding
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of explaining basic phenomena.
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Like, I'm not gonna drop the cup.
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I'll drop the water bottle.
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Okay, that fell, right?
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But why did that fall?
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This is why I'm a theorist, not an experimentalist.
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That could have gone wrong in so many ways.
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I know, it could have,
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especially if I did the cup and it smashed.
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So if you take this view
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that there's sort of some missing principles,
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I associate them to information.
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And what the sort of feeling there is,
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there's some missing explanatory framework
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for how our universe works.
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And if we understood that physics,
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it would explain what we are.
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It might also explain a lot of other features
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we don't associate to life.
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And so it's a little like people accept the fact
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that gravity is a universal phenomena.
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But when we wanna study gravity,
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we study things like large scale,
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galactic structures or black holes or planets.
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If we wanna understand information
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and how it operates in the physical world,
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we study intelligent systems or living systems
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because they are the manifestation of that physics.
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And the fact that we can't see that clearly yet,
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or we don't have that explanatory framework,
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I think it's just because we haven't been thinking
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about the problem deeply enough.
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But I feel like if you're explaining something,
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you're deriving it from some more fundamental property.
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And of course, I have to say I'm wearing my physicist hat.
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So I have a huge bias of liking simple,
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elegant explanations of the universe
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that really are compelling.
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But I think one of the things that I've sort of
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maybe in some ways rejected my training as a physicist
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is that most of the elegant explanations
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that we have so far don't include us in the universe.
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And I can't help but think
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there's something really special about what we are.
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And there have to be some deep principles at play there.
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And so that's sort of my perspective on it.
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Now, when you ask me what life is,
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I have some ideas of what I think it is,
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but I think that we haven't gotten there yet
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because we haven't been able to see that structure.
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And just to go back to the gravity example,
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it's a little like in ancient times, they didn't know,
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I was talking about stars and heavens and things.
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They didn't know those were governed by the same principles
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as that darned experiment.
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Here's where I was going with it.
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Once you realize, like Newton did,
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that heavenly motions and earthly motions
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are governed by the same principles
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and you unify terrestrial and celestial motion,
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you get these more powerful ideas.
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And I think where life is is somehow unifying
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these abstract ideas of computation and information
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with the physical world, with matter,
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and realizing that there's some explanatory framework
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that's not physics and it's not computation,
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but it's something that's deeper.
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So answering the question of what is life
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requires deeply understanding something about the universe
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as information processing, the universe is computation.
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It's something about, like would,
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once you come up with an answer to what is life,
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will the words information and computation
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be in the paragraph that answer?
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No, I don't think so.
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Oh, damn it, okay.
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I know, it doesn't help, does it?
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I know, I hate, actually I hate this about what I do
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because it's so hard to communicate, right, with words.
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Like when you have words that are ideas
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that have historically described one thing
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and you're trying to describe something
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people haven't seen yet, and the words just don't fit.
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So what's wrong, is it too ambiguous, the word information?
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We could switch to binary if you want.
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Yeah, no, I don't think it's binary either.
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I think information's just loaded.
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I use it, so the other way I might talk about it
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is the physics of causation, but I think that's worse
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because causation is even more loaded word
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So causation is fundamental, you think?
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I do, yeah, and in some sense, I think the physics,
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so this is the really radical part,
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some sense, like when I really think about it
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sort of most deeply, what I think life is
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is actually the physics of existence,
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what gets to exist and why.
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And for simple elementary particles,
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that's not very complicated
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because the interactions are simple,
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but for things like you and me and human civilizations,
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what comes next in the universe
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is really dependent on what came before,
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and there's a huge space of possibilities
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of things that can exist.
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And when I say information and causation,
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what I mean is why is it that cups evolved in the universe
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and not some other object that could deliver water
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I don't know what you would call it.
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Maybe it wouldn't be a cup, but it's a huge,
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people talk about the space of things that could exist
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as being actually infinitely large, right?
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I don't know if I believe in infinity,
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but I do think that there is something very interesting
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about the problem of what exists
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in its relationship to life.
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So do you think the set of things
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that could exist is finite?
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It's very large, but if we were to think
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about the physics of existence,
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how many shapes of mugs can there be?
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In the initial programming.
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I should go to the math department for that.
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So that's not a topology question.
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I just mean, maybe another way to ask is
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what do you think is fundamental to the universe
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and what is emergent?
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So if existence, are we supposed to think of that
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as somehow fundamental, you think?
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So there's a couple of problems in physics
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that I think this is related to.
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One is why does mathematics work
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at describing reality so well?
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And then there is this problem of we don't understand
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why the laws of physics are the way they are,
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or why certain things get to exist,
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or what put in place the initial condition of our universe.
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There's all of these sort of really deep and big problems,
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and they all indirectly are related, I think,
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to the same kind of thing that,
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our physics is really good
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if you specify the initial condition
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at specifying a certain sequence of events,
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but it doesn't deal with the fact
link |
that other things could have happened,
link |
which is kind of an informational property,
link |
like a counterfactual property.
link |
And it's not good at explaining
link |
this conversation right now.
link |
There are certain things that are outside
link |
the explanatory reach of current physics,
link |
and I think they require looking at it
link |
from a completely different direction.
link |
And so I don't wanna have to fine tune
link |
the initial condition of the universe
link |
to specify precisely all the information
link |
in this conversation.
link |
I think that's a ridiculous assertion.
link |
But that's sort of like how people wanna frame it
link |
when they talk about the standard model is sufficient
link |
if we had computing power
link |
to basically explain all of life in our existence.
link |
An interesting thing you said
link |
is the way we think about information computation
link |
is by observing a particular kind of systems on Earth
link |
that exhibit something we think of as intelligence.
link |
But that's like looking at, I guess, the tip of an iceberg,
link |
and we should be really looking at the fundamentals
link |
of the iceberg, like what makes water and ice
link |
and the chemistry from which intelligence emerges,
link |
essentially. Yes, yes.
link |
We can't just couple the information from the physics,
link |
and I think that's what we've gotten really good at doing,
link |
especially with sort of the modern age
link |
where software is so abstracted from hardware.
link |
But the entire process of biological evolution
link |
has basically been built,
link |
like been building layers of increasing abstraction.
link |
And so it's really hard to see that physics in us,
link |
but it's much clearer to see it in molecules.
link |
Yeah, but I guess I'm trying to figure out
link |
what do you think are the best tools to look at it?
link |
What do you think?
link |
What's the physics of an open mind?
link |
I think if we solve that, we'll solve everything.
link |
I'm saying an open mind
link |
because I think the biggest stumbling block
link |
to understanding sort of the things
link |
I've been trying to articulate,
link |
and when I talk also with colleagues
link |
that are thinking deeply about these same issues,
link |
is none of it is inconsistent with what we know.
link |
It's just such a radically different perception
link |
of the way we understand things now
link |
that it's hard for people to get there.
link |
And in some ways you have to almost forget
link |
what you've learned in order to learn something new, right?
link |
So I feel like most of my career
link |
trying to understand the problem of life
link |
has been variously forgetting
link |
and then relearning things that I learned in physics.
link |
And I think you have to have a capacity to learn things,
link |
but then accept that things that you learned
link |
might not be true or might need refinement or reframing.
link |
And the best way I can say that
link |
is just like with a physics education,
link |
there are just certain things you're told in undergrad
link |
that are like facts about the world.
link |
And your physics professors never tell you
link |
that those facts actually emerge from a human mind, right?
link |
So we're taught to think about,
link |
say the laws of physics, for example,
link |
as this like autonomous thing
link |
that exists outside of our universe
link |
and tells our universe how it works.
link |
But the laws of physics were invented by human minds
link |
to describe things that are regularities
link |
in our everyday experience.
link |
They don't exist autonomous to the universe.
link |
Right, so it's like turtles on top of turtles,
link |
but eventually it gets to the human mind,
link |
and then you have to explain the human mind with the turtles.
link |
So you have to, it comes from humans,
link |
this understanding, this simplification of the universe,
link |
There's a guy named Stephen Wolfram.
link |
There's a concept called cellular automata.
link |
So there's some mysteries in these systems
link |
that are computational in nature
link |
that have maybe echoes of the kind of mysteries
link |
we should need to solve to understand what is life.
link |
So if we could talk, take a computational view of things,
link |
do you think there's something compelling
link |
to reducing everything down to computation,
link |
like the universe is computation,
link |
and then trying to understand life?
link |
So throw away the biology, throw away the chemistry,
link |
throw away even the physics
link |
that you learn undergrad and graduate school,
link |
and more look at these simple little systems,
link |
whether it's cellular automata or whatever the heck
link |
kind of computational systems
link |
that operate on simple local rules
link |
and then create complexity as they evolve.
link |
Is it at all, do you think, productive
link |
to focus on those kinds of systems
link |
to get an inkling of what is life?
link |
And if it is, do you think it's possible
link |
to come up with some kind of laws and principles
link |
about what makes life in those computational systems?
link |
So I like cellular automata.
link |
I think they're good toy models,
link |
but mostly where I've thought about them and used them
link |
is to actually, let's say,
link |
poke at sort of the current conceptual framework
link |
that we have and see where the flaws are.
link |
So I think the part that you're talking about
link |
that people find intriguing is that
link |
if you have a fairly simple rule
link |
and you specify some initial condition
link |
and you run that rule on that initial condition,
link |
you could get really complex patterns emerging.
link |
And ooh, doesn't that look lifelike?
link |
Well, it's like really surprising,
link |
isn't it really surprising?
link |
It is really surprising, and they're beautiful.
link |
And I think they have a lot of nice features
link |
associated to them.
link |
I think the things that I find,
link |
yeah, so I do think as a proof of principle
link |
that you can get complex things emerging from simple rules.
link |
As a sort of proof of principle about some of the ways
link |
that we might think of computation
link |
as being sort of a fundamental principle
link |
for dynamical systems
link |
and maybe the evolution of the universe as a whole,
link |
they're a great model system.
link |
As an explanatory framework for life,
link |
I think they're a bit problematic
link |
for the same reason that the laws of physics
link |
are a bit problematic.
link |
And the clearest way I can articulate that
link |
is like cellular automata are actually cast
link |
in sort of a conceptual framework
link |
for how the universe should be described
link |
that goes all the way back to Newton, in fact,
link |
with this idea that we can have a fixed law of motion,
link |
which exists sort of, it's given to you.
link |
The great programmer in the sky gave you this equation
link |
or this rule, and then you just run with it.
link |
And the rule doesn't have,
link |
so a good feature of the rule
link |
is it doesn't have specified in the rule
link |
information about the patterns it generates.
link |
So you wouldn't want, for example,
link |
my cup or my water bottle or me sitting here
link |
to be specified in the laws of physics.
link |
That would be ridiculous
link |
because it wouldn't be a very simple explanation
link |
of all the things happening.
link |
It'd have to explain everything.
link |
So, and cellular automata have that feature
link |
and the laws of physics have that feature.
link |
But you also need to specify the initial condition.
link |
And it also, it basically means
link |
that everything that happens
link |
is sort of a consequence of that initial condition.
link |
And I think this kind of framework
link |
is just not the right one for biology.
link |
And part of the way that it's easiest to see this
link |
is a lot of people talk about self reference
link |
being important in life.
link |
The fact that, you know,
link |
like the genome has information encoded in it,
link |
that information gets read out.
link |
It specifies something about the architecture of a cell.
link |
The architecture of the cell includes the genome.
link |
So the genome has basically self referential information.
link |
Self reference obviously comes up in computational law
link |
because it's kind of foundational to Turing's work
link |
and what Gödel did with the incompleteness theorems
link |
So there's a lot of parallels there
link |
and people have talked about that at depth.
link |
But the other way of kind of thinking about it
link |
in terms of like a more physicsy way of talking about it
link |
is that what it looks like in biology
link |
is that the rules or the laws depend on the state.
link |
This is typical in computer science.
link |
This is obvious to you.
link |
You know, the update rule depends
link |
on the state of the machine, right?
link |
But, you know, you don't think about, you know,
link |
that being sort of the dynamic in physics.
link |
It's, you know, the rules given to you
link |
and then it's a very special subclass say of computations
link |
if, you know, you don't ever change the update.
link |
But in biology, it seems to be that the state
link |
and the law change together as a function of time
link |
and we don't have that as a paradigm in physics.
link |
And so a lot of people talk about this
link |
as being kind of a perplexing feature
link |
that maybe there are certain scenarios
link |
where the laws of physics
link |
or the laws that govern a particular system
link |
actually change as a function of the state of that system.
link |
So yeah, the hope of physics, it's a hope, I guess,
link |
but often stated as a underlying assumption
link |
is that the law is static.
link |
And even having laws that vary in time
link |
and not even as a function of the state is very radical.
link |
The time in general, like you wanna remove time
link |
from the equation as much as possible.
link |
There's some interesting things in this
link |
like when we think sort of more deeply
link |
about the actual physics that we're trying to propose
link |
governs life with me with collaborators
link |
and then also other people that think about similar things
link |
that time might actually be fundamental
link |
and there really is an ordering to time.
link |
And that events in the universe are unique
link |
because they have a particular, they happen,
link |
like an object in the universe
link |
requires a certain history of events in order to exist,
link |
which therefore suggests
link |
that time really does have an ordering.
link |
I'm not talking about the flow of time
link |
and our perception of time, just the ordering of events.
link |
Causation of things.
link |
Yes, causation, there's that word again.
link |
So causation, that's when you say time, you mean causation.
link |
In your proposed model of the physics of life,
link |
the fundamental thing would be causation.
link |
If you were to bet your money
link |
on one particular horse or whatever.
link |
And then space is emergent.
link |
So everything's emergent except time.
link |
Kind of, yeah, or causation.
link |
And laws change all the time.
link |
Why does it look like laws are the same?
link |
Laws, well, because, well, one way,
link |
and I actually, this idea comes from Lee Cronin
link |
because I work with him very closely on these things,
link |
is that the laws of physics look the way they do
link |
because they're low memory laws.
link |
So they don't require a lot of information to specify them.
link |
They're very easy for the universe to implement.
link |
But if you get something like me, for example,
link |
I require 4 billion year history to exist in the universe.
link |
I come with a lot of historical baggage.
link |
And that's part of what I am
link |
as a set of causes that exist in the universe.
link |
So I have local rules that apply to me
link |
that are associated with sort of the information
link |
in my history that aren't universal
link |
to every object in the universe.
link |
And there are some things that are very easy
link |
to implement low memory rules
link |
that apply to everything in the universe.
link |
So there's no shortcuts to you.
link |
No, so yeah, I don't believe in things like Boltzmann brains
link |
or fluctuations out of the vacuum
link |
that can produce things like your desk ornaments.
link |
I actually think they require
link |
a particular causal chain of events to exist.
link |
Well, I appreciate the togetherness of that,
link |
but so how does that,
link |
if we have to simulate the entire universe
link |
to create the ornaments in the two of us,
link |
how are we supposed to create engineer life in the lab?
link |
This goes back to sort of the critique of the RNA world.
link |
I think one of the problems,
link |
and I'll get to answer your question,
link |
but I think this is kind of relevant here.
link |
One of the problems with the RNA world,
link |
when we test it in the laboratory,
link |
is how much information we're putting into the experiment.
link |
We specify the flasks, we make pure reagents,
link |
we mix them, we take them out,
link |
we put them in the next flask,
link |
we change the pH, we change the UV light,
link |
and then we get a molecule,
link |
and it's not even an RNA molecule necessarily,
link |
it might just be a base, right?
link |
And so people don't usually think about the fact
link |
that we're agents in the universe making that experiment,
link |
and therefore we put a little bit of life
link |
into that experiment,
link |
because it's part of our biological lineage,
link |
in the same sense that I am a part of the biological lineage.
link |
The experiment is.
link |
I mean, our ideas are injecting life.
link |
And the constraints that we put on the experiments,
link |
because those conditions wouldn't exist in the universe
link |
on planet Earth at that time
link |
without us as the boundary condition, right?
link |
Even though we're not actually adding
link |
any actual chemistry or biology
link |
that could be identified as life,
link |
are the constraints we're adding to the experiment,
link |
the design of the experiment.
link |
Yeah, you can think of the design experiment as a program.
link |
You put information in.
link |
It's an algorithmic procedure that you design the experiment.
link |
And so the origin of life problem
link |
becomes one of minimizing the information
link |
we put into physics
link |
to actually watch the spontaneous origin of life.
link |
Can we have, so can, is it possible in the lab
link |
to have an information vacuum then?
link |
If we could, we would, that would be amazing.
link |
That's a good question for, more for Lee.
link |
Yeah, you guys, by the way,
link |
for people who don't know, Lee Cronin is,
link |
you guys are colleagues.
link |
I've gotten the chance to listen to the two of you talking.
link |
There's great sort of chemistry
link |
and you're brilliant brainstorming together.
link |
And there's a really exciting community here
link |
of brilliant people from different disciplines
link |
working on the problem of life, of complexity,
link |
of, I don't know, whatever.
link |
The words fail us to describe the exact problem
link |
we're trying to actually understand here.
link |
Intelligence, all those kinds of things.
link |
Okay, so what, from a lab perspective,
link |
so Lee, I guess, would you call him a chemist?
link |
I think by training he's a chemist,
link |
but I think most of the people that work in the field,
link |
we do have lost their discipline.
link |
That's why I couldn't answer your question earlier.
link |
I don't know what you call him.
link |
I don't know what I call myself.
link |
I don't know what I call any of my friends.
link |
So why is it so hard to create,
link |
and it's an interesting question,
link |
to create biological life in the lab.
link |
Like from your perspective,
link |
is that an important problem to work on
link |
to try to recreate the historical origin of life on Earth
link |
or echoes of the historical origin?
link |
I think echoes is more appropriate.
link |
I don't think asking the question
link |
of what was the exact historical sequence of events
link |
and engineering every step in the process
link |
to make exactly the chemistry of life on Earth as we know it
link |
is a meaningful way of asking the question.
link |
And it's a little bit like,
link |
since you're in computer science,
link |
like if you know the answer to a problem,
link |
it's easier to find a program to specify the output, right?
link |
But if you don't know the answer a priori,
link |
finding an algorithm for it,
link |
like say finding a prime or something,
link |
it's easy to verify it's a prime number.
link |
It's hard to find the next prime.
link |
And the way the origin of life is structured right now
link |
in the historical problem is you know the answer
link |
and you're trying to retrodict it by breaking it down
link |
into the set of procedures
link |
where you're putting a lot of information in.
link |
And what we need to do is ask the question
link |
of how is it that the rules of how our universe is structured
link |
permit things like life to exist
link |
and what is the phenomena of life?
link |
And those questions are obviously
link |
essentially the same question.
link |
And so you're looking essentially for this missing physics,
link |
this missing explanation for what we are,
link |
and you need to set up proper experiments
link |
that are gonna allow you to probe
link |
the vast complexity of chemistry in an unconstrained way
link |
with as little information put in as possible
link |
to see when things, when does information actually emerge?
link |
How does it emerge?
link |
And part of the sort of conjecture we have
link |
is that this physics only becomes relevant
link |
or at least this is my personal conjecture
link |
and it's sort of validated
link |
by this kind of theory experiment collaboration
link |
that we have working in this area that this, you know,
link |
sort of, I made the point about like gravity
link |
existing everywhere, right?
link |
But when you study an atomic nucleus,
link |
you don't care about gravity.
link |
It's not relevant physics there, right?
link |
It's weak, it doesn't matter.
link |
And so this idea that there's kind of a physics
link |
associated with information,
link |
for me, it's very evident that that physics
link |
doesn't become relevant until you need information
link |
to specify the existence of a particular object.
link |
And the scale of reality where that happens
link |
is in chemistry because of the combinatorial diversity
link |
of chemical objects that can exist far out,
link |
exceeds the amount of resources in our universe.
link |
So if you want it, you can't make every possible protein
link |
of length, you know, 200 amino acids,
link |
there's not enough resources.
link |
So in order for this particular protein to exist
link |
and this protein to exist in high abundance
link |
means that you have to have a system that has knowledge
link |
of the existence of that protein and can build it.
link |
So existence comes to be at the chemical level.
link |
So existence is most, is best understood
link |
at the chemical level.
link |
It's most evident.
link |
It's a little bit like, nobody argues that gravity
link |
doesn't exist in an atomic nucleus.
link |
It's just not relevant physics there, right?
link |
So the physics of information.
link |
It exists at every combinatorial scale,
link |
but it becomes more and more relevant
link |
the more set of possibilities that could exist
link |
because you have to specify more and more
link |
about why this thing exists and not the infinite.
link |
It's not an infinite set, but you know,
link |
the set of undefined set of other things that could exist.
link |
So can I ask a weird question, which is,
link |
so let's look into the future.
link |
I try that every day.
link |
So say a Nobel prize is given in physics,
link |
maybe chemistry for discovering the origin of life.
link |
No, but not the historical origin.
link |
Some kind of thing that we're talking about.
link |
What exactly would, what do you think that,
link |
like, what do you think that person,
link |
maybe you did to get that Nobel prize?
link |
Like what would they have to have done?
link |
Cause you can do a bunch of experiments that go
link |
like within the aha moment.
link |
Like you rarely get the Nobel prize for like,
link |
you've solved everything, we're done.
link |
It's like some inkling of some deep truth.
link |
Like what do you think that would actually look like?
link |
Would it be an experimental result?
link |
I mean, it will have to have some kind of experimental,
link |
maybe validation component.
link |
So what would that look like?
link |
This is an excellent question.
link |
I want to, sorry, I'm going to make a quick point,
link |
which is just a slight tangent.
link |
But you know, like when people ask about the origin of mass,
link |
and like looking for the Higgs mechanism and things,
link |
they never are like,
link |
we need to find the historical origins of life
link |
in the early unit.
link |
Although those things are related, right?
link |
So this problem of origins of life in the lab,
link |
I think is really important.
link |
But the Higgs is a good example
link |
because you had theory to guide it.
link |
So somehow you need to have an explanatory framework
link |
that can say that we should be looking for these features
link |
and explain why they might be there
link |
and then be able to do the experiment
link |
and demonstrate that it matches with the theory.
link |
But it has to be something that is outside
link |
sort of the paradigm of what we might expect
link |
based on what we know, right?
link |
So this is a really sort of tall order.
link |
And I think, I mean, I guess the way people would think
link |
about it is like, you know,
link |
if you had a bacteria that climbed out of your test tube
link |
or something, and it was like, you know,
link |
moving around on the surface,
link |
that would be ultimate validation.
link |
You saw the origin of life in an experiment,
link |
but I don't think that's quite what we're looking for.
link |
I think what we're looking for is evidence
link |
of when information that originated
link |
within the bounds of your experiment
link |
and you can demonstrably prove emerged spontaneously
link |
in your experiment, wasn't put in by you,
link |
actually started to govern the future dynamics
link |
of that system and specify it.
link |
And you could somehow relate those two features directly.
link |
So you know that the program specifying
link |
what's happening in that system
link |
is actually internal to that system.
link |
Like say you have a chemical thing in a box.
link |
Well, so that's one Nobel Prize winning experiment,
link |
which is like information in some fundamental way
link |
originated within the constraints of the system
link |
without you injecting anything.
link |
But another experiment is you injected something.
link |
And got out information.
link |
So like you injected, I don't know,
link |
like some sugar and like something that doesn't necessarily
link |
feel like it should be information.
link |
Yeah, so I actually know, I mean,
link |
sugar is information, right?
link |
So part of the argument here is that every physical object
link |
is, well, it's information,
link |
but it's a set of causal histories
link |
and also a set of possible futures.
link |
So there is an experiment that I've talked a lot about
link |
with Lee Cronin, but also with Michael Lockman
link |
and Chris Kempis who are at Santa Fe
link |
about this idea that sometimes we talk about
link |
as like seeding assembly,
link |
which is you take a high complexity,
link |
like an object that exists in the universe
link |
because of a long causal history,
link |
and you seed it into a system of lower causal history.
link |
And then suddenly you see all of this complexity
link |
So I think another validation of the physics would be,
link |
say you engineer an organism
link |
by purposefully introducing something
link |
where you understand the relationship
link |
between the causal history of the organism
link |
and the say very complex chemical set of ingredients
link |
you're adding to it.
link |
And then you can predict the future evolution of that system
link |
to some statistical set of constraints and possibilities
link |
for what it will look like in the future.
link |
I'm a physical structure, obviously,
link |
like I'm composed of atoms,
link |
the configuration of them
link |
and the fact that they happen to be me
link |
is because I'm not actually my atoms,
link |
I am a informational pattern
link |
that keeps re patterning those atoms into Sarah.
link |
And I have also associated to me
link |
like a space of possible things that could exist
link |
that I can help mediate come into existence
link |
because of the information in my history.
link |
And so when you understand sort of that
link |
time is a real thing embedded in a physical object,
link |
then it becomes possible to talk about
link |
how histories when they interact
link |
and a history is not a unique thing,
link |
it's a set of possibilities.
link |
When they interact,
link |
how do they specify what's coming next?
link |
And then where does the novelty come from in that structure?
link |
Cause some of it is kind of things
link |
that haven't existed in the past can exist in the future.
link |
Let me ask about this entity that you call Sarah.
link |
I talk to myself about myself in third person sometimes.
link |
So maybe this is a good time to bring up consciousness.
link |
It's been here all along.
link |
So, I mean that's.
link |
At least in this conversation,
link |
I think I've been conscious most of it,
link |
but maybe I haven't.
link |
So speak for yourself.
link |
You're projecting your consciousness onto me.
link |
You don't know if I'm conscious or not.
link |
Is that, you talked about the physics of existence,
link |
you talked about the emergence of causality,
link |
sorry, you talked about causality and time
link |
being fundamental to the universe.
link |
Where does consciousness fit into all of this?
link |
Like, do you draw any kind of inspiration or value
link |
with the idea of panpsychism
link |
that maybe one of the things that we ought to understand
link |
is the physics of consciousness?
link |
Like one of the missing pieces in the physics view
link |
of the world is understanding the physics of consciousness.
link |
Or like that word has so many concepts underneath it,
link |
but let's put consciousness as a label
link |
on a black box of mystery that we don't understand.
link |
Do you think that black box holds the key
link |
to finally answering the question
link |
of the physics of life?
link |
The problems are absolutely related.
link |
I think most, and I'm interested in both
link |
because I'm just interested in what we are.
link |
And to me, the most interesting feature
link |
of what we are is our minds
link |
and the way they interact with our minds.
link |
Like minds are the most beautiful thing
link |
that exists in the universe.
link |
So how do they come to be?
link |
Sorry to interrupt.
link |
So when you say we, you mean humans.
link |
I mean humans right now, but that's because I'm a human.
link |
Or at least I think I am.
link |
But you think there's something special
link |
to this particular?
link |
No, no, no, no, no.
link |
No, I'm not a human centric thinker.
link |
But are you one entity?
link |
You said a bunch of stuff came together to make a Sarah.
link |
Like do you think of yourself as one entity
link |
or are you just a bunch of different components?
link |
Like is there any value to understand the physics of Sarah?
link |
Or are you just a bunch of different things
link |
that are like a nice little temporary side effect?
link |
Yeah, you could think of me as a bundle of information
link |
that just became temporarily aggregated
link |
into your individual, yeah.
link |
I agree with that view.
link |
I'll take that as a compliment actually.
link |
But nevertheless, that bundle of information
link |
has become conscious.
link |
Or at least keeps calling herself conscious.
link |
Yeah, I think I'm conscious right now,
link |
but I might not be, but that's okay.
link |
Or you wouldn't know.
link |
So yeah, so this is the problem.
link |
So yeah, usually people when they're talking
link |
about consciousness are worried
link |
about the subjective experience.
link |
And so I think that's why you're saying,
link |
I don't know if you're conscious
link |
because I don't know if you're experiencing
link |
this conversation right now.
link |
And nor do you know if I'm experiencing
link |
the conversation right now.
link |
And so this is why this is called
link |
the hard problem of consciousness
link |
because it seems impenetrable from the outside
link |
to know if something's having a conscious experience.
link |
And I really like the idea of also
link |
like the hard problem of matter,
link |
which is related to the hard problem of consciousness,
link |
which is you don't know the intrinsic properties
link |
of an electron not interacting,
link |
say for example, with anything else in the universe.
link |
All the properties of anything that exists
link |
in the universe are defined by its interaction
link |
because you have to interact with it
link |
in order to be able to observe it.
link |
So we can only actually know the things
link |
that are observable from the outside.
link |
And so this is one of the reasons
link |
that consciousness is hard for science
link |
because you're asking questions
link |
about something that's subjective
link |
and supposed to be intrinsic to what that thing is
link |
as it exists and how it feels about existing.
link |
And so I have thought a lot about this problem
link |
and its relationship to the problem of life.
link |
And the only thing I can come up with
link |
to try to make that problem scientifically tractable
link |
and also relate it to how I think about the physics of life
link |
is to ask the question,
link |
are there things that can only happen in the universe
link |
because there are physical systems
link |
that have subjective experience?
link |
So does subjective experience have different causes
link |
that things that it can cause to occur
link |
that would happen in the absence of that?
link |
I don't know the answer to that question,
link |
but I think that's a meaningful way
link |
of asking the question of consciousness.
link |
I can't ask if you're having experience right now,
link |
but I can ask if you having experience right now
link |
changes something about you
link |
and the way you interact with the world.
link |
So does stuff happen?
link |
It's a good question to ask, does stuff happen
link |
if consciousness is?
link |
Then it's a real physical thing, right?
link |
It has physical consequences.
link |
I'm a physicist, I'm biased,
link |
so I can't get rid of that bias.
link |
It's really deeply ingrained.
link |
I've tried, but it's hard.
link |
But I mean, you're saying information is physical too.
link |
So like virtual reality, simulation,
link |
all that program is physical too in the sense of.
link |
Yes, everything's physical.
link |
It's just not physical the way it's represented in our minds.
link |
Right, so you, I love your Twitter.
link |
So you tweet these like deep thoughts, deep thoughts.
link |
That's what a theorist does
link |
when she's trying to experiment.
link |
It's just like sitting there.
link |
I mean, I could just imagine you sitting there
link |
for like hours and all of a sudden just like
link |
this thought comes out and you get a little
link |
like inkling into the thought process.
link |
Yeah, usually it's like when I'm running between things
link |
and not so much when I've had deep thoughts.
link |
Well, yeah, so you.
link |
Deep thoughts are hard to articulate.
link |
One of the things you tweeted is,
link |
ideologically, there are many parallels
link |
between the search for neural correlates of consciousness
link |
and for chemical correlates of life.
link |
How the neuroscience and astrobiology communities
link |
treat those correlates is entirely different.
link |
Can you elaborate against this kind of the parallels?
link |
It has to do a little bit with the consciousness
link |
and the matter thing you're talking about.
link |
And I can't remember what state of mind I was
link |
when I was actually thinking about that.
link |
But I think part of it is.
link |
I bet you never thought you were gonna have
link |
to analyze your own tweets.
link |
It's an interesting historical juxtaposition of thinking.
link |
So the tweet is a historical.
link |
You're doing an assembly experiment right now
link |
because you're bringing a thought from the past
link |
into the present and trying to actually.
link |
This is experimental science right here
link |
on the podcast live.
link |
So go, let's see how the consciousness evolves on this one.
link |
Yeah, so in neuroscience, it's kind of accepted
link |
that we can't get at the subjective aspect
link |
So people are very interested in what would be a correlate
link |
What's a correlate?
link |
A correlate is a feature that relates
link |
to conscious activity.
link |
So for example, a verbal report is a correlate
link |
of consciousness because I can tell you when I'm conscious.
link |
And then when I'm sleeping, for example,
link |
I can't tell you I'm conscious.
link |
So we have this assumption that you're not conscious
link |
when you're sleeping and you're conscious when you're awake.
link |
And so that's sort of like a very obvious example,
link |
but neuroscientists, which I'm no neuroscientist
link |
and I'm not an expert in this field.
link |
So, but they have very sophisticated ways of measuring
link |
activity in our brain and trying to relate that
link |
to verbal report and other proxies for whether someone
link |
is experiencing something.
link |
And that's what is meant by neural correlates.
link |
And then, so when people are trying to think
link |
about studying consciousness or developing theories
link |
for consciousness, they often are trying to build
link |
an experimental bridge to these neural correlates,
link |
recognizing the fact that a neural correlate
link |
may or may not correspond to consciousness
link |
because that problem's hard
link |
and there's all these associated issues to it.
link |
So that's, from a neuroscience perspective,
link |
it's like fake it till you make it.
link |
So you. Pretty much, yeah.
link |
You fake whatever the correlates are and hopefully
link |
that's going to summon the thing that is consciousness.
link |
Yeah, something like that.
link |
And so the same thing on the chemical correlates of life.
link |
That sounds like, that's an awesome concept.
link |
Is that something that people?
link |
No, I just made that up.
link |
That was original to that tweet.
link |
You can cite the tweet.
link |
Maybe I'll write it in a paper someday.
link |
Chemical correlates of life, that's a good title.
link |
I mean, first of all, your paper is true
link |
that people should check out, have great titles.
link |
Or papers you're involved with.
link |
So your tweets and titles are stellar and also your ideas,
link |
but the tweets and titles are much more important.
link |
So. Ideas will live longer.
link |
They're much more diffused though.
link |
Well, it's, yeah, it's the Trojan,
link |
the tweet is the Trojan horse of the idea
link |
that sticks on for a long time.
link |
Okay, so is there anything to say
link |
about the chemical correlates of life?
link |
You're saying they're similar kind of ways
link |
of thinking about it,
link |
but you mentioned about the communities.
link |
Yeah, so I think in astrobiology, it's not,
link |
there's no concept of chemical correlates of life.
link |
We don't think about it that way.
link |
We think if we find molecules that are involved in biology,
link |
So I think one of my motivations there
link |
was just to separate the fact
link |
that life has abstract properties associated to it.
link |
They become imprinted in material substrates
link |
and those substrates are correlates for that thing,
link |
but they are not necessarily
link |
the thing we're actually looking for.
link |
The thing that we're looking for is the physics
link |
that's organizing that system to begin with,
link |
not the particular molecules.
link |
In the same sense that, you know,
link |
your consciousness is not your brain.
link |
It's instantiated in your brain.
link |
You know, it has to have a physical substrate,
link |
but it's not, the matter is not the thing
link |
that you're looking at.
link |
It's some other, at least not in the way
link |
that we have come to look at matter,
link |
you know, with traditional physics and things.
link |
There's something else there
link |
and it might be this feature of history
link |
I was talking about,
link |
our time being actually, you know,
link |
physically represented there.
link |
Do you think consciousness can be engineered?
link |
In the same way that life can be engineered?
link |
Well, that was a fast answer.
link |
I didn't even think about that.
link |
That's interesting.
link |
You don't have a free will.
link |
That was predestined.
link |
No, I do have free will,
link |
but it's interesting,
link |
because I mean, you know,
link |
Now you're backtracking.
link |
And that was predestined.
link |
No, I do believe in free will,
link |
but I also think that there's kind of an interesting,
link |
you know, like what you're speaking about consciousness.
link |
What are you consciously aware of
link |
versus like what is your subconscious brain
link |
actually processing and doing?
link |
And sometimes there's conflict between your consciousness
link |
and your subconsciousness
link |
or your consciousness is a little slower
link |
than your subconscious.
link |
And intuition is a really important feature of that.
link |
And so a lot of the ways I do my science
link |
is guided by intuition.
link |
So when I give fast answers like that,
link |
I think it's usually
link |
because I haven't really thought about them
link |
and therefore that's probably telling me something.
link |
Let's continue the deep analysis of your tweets.
link |
You said that determinism in a tweet,
link |
determinism and randomness play important roles
link |
in understanding what life is.
link |
So let me ask on this topic of free will,
link |
what is determinism, what is randomness
link |
and why the heck do they have anything to do
link |
with understanding life?
link |
Yeah, and you threw free will in there,
link |
just throwing all the stuff in the bag.
link |
Are they not related, determinism and randomness?
link |
No, no, they are related.
link |
No, no, that's all right.
link |
I was being unfair.
link |
You didn't even capitalize the tweet, by the way.
link |
It was all lowercase.
link |
I must've been angry.
link |
Oh, that was saying,
link |
can you analyze the emotion behind that?
link |
No, I actually did.
link |
Is it frustration or is it hope?
link |
So I already argued that I don't think that can happen
link |
without that whole causal history.
link |
And so I guess in some sense,
link |
the determinism for me arises because of the causal history.
link |
And I'm not really sure actually
link |
about whether the universe is random or deterministic.
link |
I just had this sort of intuition for a long time.
link |
I'm not sure if I agree with it anymore,
link |
but it's still kind of lingering
link |
and I don't know what to do with this question.
link |
But it seems to me, you know,
link |
so you asked the question, what is life?
link |
But you could also, why life?
link |
Why does life exist?
link |
What does the universe need life for?
link |
Not that the universe has needs,
link |
but you know, we have to anthropocentrize things sometimes
link |
to talk about them.
link |
And I had this feeling that if it was possible
link |
for a cup or a desk ornament or a phone on Mars
link |
to spontaneously fluctuate into existence,
link |
the universe didn't need life to create those objects.
link |
It wasn't necessary for their existence.
link |
It was just a random fluke event.
link |
And so somehow to me,
link |
it seems that it can't be that those things
link |
formed by random processes,
link |
they actually have to have a set of causes
link |
that accrue and form those things
link |
and they have to have that history.
link |
And so it seems to me that that life
link |
was somehow deeply related to the question
link |
of whether the underlying rules of our universe
link |
had randomness in them or they were fully deterministic.
link |
And in some ways you can think about life
link |
as being the most deterministic part of physics
link |
because it's where the causes are precise in some sense.
link |
So like I'm trying...
link |
Most stable, yes, most reliable.
link |
Most reliable for the tools of physics.
link |
But where's the randomness come from then?
link |
Okay, so you were speaking with...
link |
I've gone in a tangent,
link |
so I'm not sure where we are in the...
link |
All of the universe is a kind of tangent.
link |
So we're embracing the tangent.
link |
So free will, you believe at this current time
link |
that you have free will.
link |
I believe my whole life I have free will.
link |
I still believe it.
link |
You still believe it.
link |
So at the same time you think that
link |
in your conception of the universe,
link |
causality seems to be pretty fundamental.
link |
Which kind of wants the universe to be deterministic.
link |
So how the heck do you think you have a free will
link |
and yet you value causality?
link |
Because I depart from the conception of physics
link |
that you can write down an initial condition
link |
and a fixed law of motion and that will describe everything.
link |
There's no incompatibility
link |
if you are willing to reject that assertion.
link |
So where's the randomness?
link |
Where's the magic that gives birth to the free will?
link |
Is it the randomness of the laws of physics?
link |
No, in my mind what free will is,
link |
is the fact that I as a physical system
link |
have causal control over certain things.
link |
I don't have causal control over everything,
link |
but I have a certain set of things.
link |
And I'm also, as I described,
link |
sort of a nexus of a particular set of histories
link |
that exist in the universe
link |
and a particular set of futures that might exist.
link |
And those futures that might exist are in part specified
link |
by my physical configuration as me.
link |
And therefore, it may not be free will
link |
in the traditional sense.
link |
I don't even know what people mean
link |
when they're talking about free will, honestly.
link |
It's like the whole discussion's really muddled.
link |
But in the sense that I am a causal agent,
link |
if you wanna call it that, that exists in the universe,
link |
and there are certain things that happen
link |
because I exist as me, then yes, I have free will.
link |
No, but do you, Sarah, have a choice
link |
about what's going to happen next?
link |
If the universe, could I have,
link |
if I run this universe. Yes, I think so.
link |
You have a choice.
link |
Where does the choice come from?
link |
I think that's related to the physics of consciousness.
link |
So one of the things I didn't say about that,
link |
I don't know, maybe this is me just being hopeful
link |
because maybe I just wanna have free will,
link |
but I don't think that we can rule out the possibility
link |
because I don't think that we understand enough
link |
about any of these problems.
link |
But I think one of the things that's interesting for me
link |
about the sort of inversion of the question
link |
of consciousness that I proposed
link |
is one of the features that we do
link |
is we have imagination, right?
link |
And people don't think about imagination
link |
as a physical thing, but it is a physical thing.
link |
It exists in the universe, right?
link |
And so I'm like really intrigued by the fact that say,
link |
humans for, another physical system could do this too,
link |
it's not special to humans,
link |
but for centuries imagined flying machines and rockets,
link |
and then we finally built them, right?
link |
So they were represented in our minds
link |
and on the pages of things that we drew
link |
for hundreds of years before we could build
link |
those physical objects in the universe.
link |
But certainly the existence of rockets
link |
is in part causally,
link |
caused by the fact that we could imagine them.
link |
And so there seems to be this property
link |
that some things don't exist,
link |
they've never physically existed in the universe,
link |
but we can imagine the possibility of them existing
link |
and then cause them to exist,
link |
maybe individually or collectively.
link |
And I think that property is related
link |
to what I would say about having choice or free will,
link |
because that set of possibilities,
link |
those set of things that you can imagine
link |
is not constrained to your local physical environment
link |
And this is what's a little bit different
link |
about intelligence as we see it in humans
link |
and AI that we wanna build than biological intelligence,
link |
because biological intelligence is predicated completely
link |
on the history of things that's seen in the past,
link |
but something happened with the neural architectures
link |
that evolved in multicellular organisms
link |
that they don't just have access to the past history
link |
of their particular set of events,
link |
but they can imagine things that haven't happened,
link |
aren't on their timeline,
link |
and as long as they're consistent with the laws of physics,
link |
So this is fascinating.
link |
It's trippy physics, but it exists, so there you go.
link |
I mean, in some sense,
link |
if you look at like general relativity and gravity
link |
morphing space time in that same way,
link |
maybe whatever the physics of consciousness might be,
link |
it might be morphing, that's like what free will is.
link |
It's morphing like the space,
link |
just like ideas make rockets come to life.
link |
It's somehow changing the space of possible realizations
link |
of like whatever's, yeah, okay, but that's.
link |
Life is kind of basically, if you wanna think about it,
link |
like life is sort of changing the probability distributions
link |
over what can exist.
link |
That's the physics of what life is.
link |
And then consciousness is this sort of layered property
link |
or imagination on top of it
link |
that kind of scrambles that a little bit more
link |
and like has access to, I don't know.
link |
It's kind of, we don't know how to describe it, right?
link |
Like that's why it's interesting, but.
link |
But it's probabilistic.
link |
So you do think like God plays dice.
link |
No, I think the description is probabilistic.
link |
I don't necessarily think
link |
the underlying physics is probabilistic.
link |
I think the way that we can describe this physics
link |
is going to be probabilistic and statistical,
link |
but the under, like when we take measurements in the lab,
link |
but the underlying physics itself
link |
might still be deterministic.
link |
Maybe I'm, it's hard to know what concepts to hold on to.
link |
So I find myself constantly rejecting concepts,
link |
but then I have to grab another one
link |
and try to hold onto something from intellectual history.
link |
Well, it's possible that our mind
link |
is not able to hold the correct concepts in mind at all.
link |
Like we're not able to even conceive of them correctly.
link |
Maybe the word's deterministic or random
link |
or not the right even words, concepts to be holding.
link |
But maybe you can talk to the theory of everything,
link |
this attempt in the current set of physical laws
link |
to try to unify them.
link |
Is there any hope that once a theory of everything
link |
is developed, and by theory of everything,
link |
I mean in a narrow sense of unifying quantum field theory
link |
and general relativity,
link |
do you think that will contain some,
link |
like in order to do that unification,
link |
you would have to get something
link |
that would then give hints about the physics of life,
link |
physics of existence, physics of consciousness.
link |
Yeah, I used to not, but I actually,
link |
I have become increasingly convinced that it probably will.
link |
And part of the reason is,
link |
I think I've talked a little bit already
link |
about these holes in physics,
link |
like the theories we have in physics,
link |
they have problems, they have lots of problems
link |
and they're very deep problems
link |
and we don't know how to patch them.
link |
And some of those problems become very evident
link |
when you try to patch quantum mechanics
link |
and general relativity together.
link |
So there is this kind of interesting feature
link |
that some of the ways of patching that
link |
might actually closely resemble the physics of life.
link |
And so the place where that actually comes up most,
link |
and actually we just had a workshop
link |
in the Beyond Center where I work
link |
at Arizona State University,
link |
and Lee Smolin made this point that he thinks
link |
that the theory of quantum gravity when we solve it
link |
is gonna be the same theory that gives rise to life.
link |
And I think that I agree with him on some levels
link |
because there's something very interesting where,
link |
if you look at these sort of causal set theories of gravity
link |
where they're looking for space as being emergent.
link |
And so space time is an emergent concept from a causal set,
link |
which is also sort of related, I think,
link |
to what Wolfram's doing with his physics project.
link |
It's the same kind of underlying math
link |
that we have in this theory that we've been developing
link |
related to life called assembly theory,
link |
which is basically trying to look at complex objects
link |
like molecules and bacteria and living things
link |
as basically being assembled from a set of component parts
link |
and that they actually encode all the possible histories
link |
that they could have in that physical object.
link |
So mathematically, all these ideas I think are related.
link |
I think a lot of people are thinking about this
link |
from different perspectives.
link |
And then constructor theory that David Deutsch
link |
and Chiara Marletto have been developing
link |
is a totally different angle on it,
link |
but I think getting at some similar ideas.
link |
So it's a really interesting time right now, I think,
link |
for the frontiers of physics and how it's relating
link |
to maybe deeper principles about what life is.
link |
So short answer, yes.
link |
Long winded answer, rewind.
link |
Can we talk about aliens?
link |
So one, I think one interesting way to sneak up
link |
on the question of what is life is to ask
link |
what should we look for in alien life?
link |
If we were to look out into our galaxy and into the universe
link |
and come up with a framework of how to detect alien life,
link |
what should we be looking for?
link |
Is there like set of rules, like it's both the tools
link |
and the tools that are service sensors
link |
for certain kind of properties of life.
link |
So what should we look for in alien life?
link |
Yeah, so we have a paper actually coming out on Monday,
link |
which is collaboration.
link |
It's actually really Lee Cronin's lab,
link |
but my group worked with him on it
link |
and we're working on the theory,
link |
which is this idea that we should look for life
link |
as high assembly objects.
link |
What we mean by that is,
link |
which is actually observationally measurable.
link |
And this is one of the reasons that I started working
link |
with Lee on these ideas is because being a theorist,
link |
it's easy to work in a vacuum.
link |
It's very hard to connect abstract ideas
link |
about the nature of life to anything
link |
that's experimentally tractable.
link |
But what his lab has been able to do is develop this method
link |
where they look at a molecule
link |
and they break it apart into all its component parts.
link |
And so you say you used to have
link |
some elementary building blocks
link |
and you can build up all the ways of putting those together
link |
to make the original object.
link |
And then you look for the shortest path in that space.
link |
And you say that's sort of the assembly number
link |
associated to that object.
link |
And if that number is higher,
link |
it assumes that a longer causal history
link |
is necessary to produce that object
link |
or more information is necessary to specify
link |
the creation of that object in the universe.
link |
Now, that kind of idea at a superficial level
link |
has existed for a long time.
link |
That kind of idea as a physical observable of molecules
link |
is completely novel.
link |
And what his lab has been able to show
link |
is that if you look at a bunch of samples
link |
of nonbiological things and biological things,
link |
there's this kind of threshold of assembly
link |
where as far as the experimental evidence is
link |
and also your intuitive intuition would suggest
link |
that nonbiological systems don't produce things
link |
with high assembly number.
link |
So this goes back to the idea
link |
like a protein is not gonna spontaneously fluctuate
link |
into existence on the surface of Mars.
link |
It requires an evolutionary process
link |
and a biological architecture to produce a protein.
link |
You generalize that argument,
link |
a complex molecule or a cup or a desk ornament
link |
in this sort of abstract idea of assembly spaces
link |
as being the causal history of objects.
link |
And you can talk about the shortest path
link |
from elementary objects to an object
link |
given an elementary set of operations.
link |
And you can experimentally measure that with mass spec.
link |
And that's basically the sort of the idea.
link |
That's really fascinating.
link |
I can't get out of my head.
link |
I'd start imagining Legos
link |
and all the Legos I've ever built and how many steps,
link |
what is the shortest path to the final little Lego castles?
link |
So then like asking about going to look for alien life,
link |
the idea is most of the instruments that NASA builds,
link |
for example, or any of the space agencies
link |
looking for life in the universe
link |
are looking for chemical correlates of life, right?
link |
But here we have something
link |
that is based on properties of molecules.
link |
It's not a chemical correlate, it's agnostic.
link |
It doesn't care about the molecule.
link |
It cares about what is the history
link |
necessary to produce this molecule?
link |
How complex is it in terms of how much time is needing,
link |
how much information is required to produce it?
link |
So when you observe a thing on another planet,
link |
you're essentially,
link |
the process looks like a reverse engineering,
link |
trying to figure out what is the shortest path
link |
to create that thing.
link |
Yeah, so most, yeah, and I would say most,
link |
like most examples of biology or technology
link |
don't take the shortest path, right?
link |
But the shortest path is a bound on how hard it is
link |
for the universe to make that.
link |
Yeah, and I guess what you and Lee are saying
link |
that there's a heuristic,
link |
that's a good metric for like better perhaps
link |
than chemical correlates.
link |
Yes, because it doesn't, it's not contingent
link |
on looking for the chemistry of life on earth,
link |
And it also has a deeper explanatory framework
link |
as far as the kind of theory that we're trying to develop
link |
associated to what life is.
link |
And I think this is one of the problems I have
link |
in my field personally in astrobiology
link |
is people observe something on earth,
link |
say oxygen in the atmosphere or an amino acid in a cell,
link |
and then they say, let's go look for that on another planet.
link |
Let's look for oxygen on exoplanets
link |
or let's look for amino acids on Mars.
link |
And then they assume that's a way of looking for life
link |
or even phosphine on Venus.
link |
But you know, like there's all these examples
link |
of let's look for one molecule.
link |
A molecule is not life.
link |
Life is a system that patterns particular structures
link |
That's like, that's what it is.
link |
And it doesn't care what molecules are there.
link |
It's something about the patterns and that structure
link |
And if you're looking for a molecule,
link |
you're not testing any hypotheses
link |
about the nature of what life is.
link |
It doesn't tell me anything.
link |
If we discover oxygen on an exoplanet
link |
about what kind of life is there,
link |
just oxygen on an exoplanet.
link |
It's not, there's, I guess I think like,
link |
when you think about the question,
link |
are we alone in the universe?
link |
That's a pretty fricking deep question.
link |
It should have a fricking deep answer.
link |
It shouldn't just be, there's a molecule on an exoplanet.
link |
Wow, we solved the problem.
link |
It should tell us something meaningful about our existence.
link |
And I feel like we've fallen short
link |
on how we're searching for life
link |
in terms of actually searching for things like us
link |
in this kind of deeper way.
link |
But how do you do that initial kind of,
link |
say I'm walking down the street
link |
and I'm looking for that double take test of like,
link |
like what the hell is that?
link |
Like that initial, like how do we look for
link |
the possibility of weirdness
link |
or the possibility of high assembly number?
link |
Like what would aliens look like
link |
if they don't have two eyes and are green?
link |
If I knew, I wouldn't probably already solve the problem.
link |
Right, there's another Nobel Prize in there somewhere.
link |
Yeah, somewhere in there.
link |
Well, I think it's kind of,
link |
so there is a bias here, right?
link |
So we've evolved to recognize life on earth, right?
link |
Like I, you know, children at a very early age
link |
can tell the difference between a puppy and a plant
link |
and then the plant and a chair, for example.
link |
You know, like it just, it seems innate.
link |
And so I think, and also because we're life,
link |
you know, I think like there's this implicit bias
link |
that we should know it when we see it
link |
and it should be completely obvious to us.
link |
But there are a lot of features of our universe
link |
that are not completely obvious to us.
link |
Like the fact that this table is made of atoms
link |
and that I'm sitting
link |
in a gravitational potential well right now.
link |
And I guess my point with this is,
link |
I think life is much less obvious than we think it is.
link |
And so it could be in many more forms
link |
than we think it is.
link |
And I guess this goes back to the point
link |
about being open minded
link |
that we may not know what alien life looks like.
link |
It might not even be possible to interact with alien life
link |
because maybe something about, you know,
link |
our informational lineage, it makes it impossible
link |
for information from an alien to be copied to us.
link |
Therefore there's no, you know,
link |
so to speak communication channel.
link |
And I don't mean, you know, verbal communication,
link |
just it's not in our observational space.
link |
Like, you know, there's fundamental questions
link |
about why we observe the universe in position
link |
rather than momentum, but we also, you know,
link |
observe it in terms of certain informational patterns
link |
and things like that's what our brain constructs
link |
and maybe aliens just interact
link |
with a different part of reality than we do.
link |
That's wildly speculative, but I think, I think.
link |
But it's possible.
link |
It's possible and I think it's consistent with the physics.
link |
So I think the best ways we can ask questions
link |
are about life and chemistry
link |
and asking questions about
link |
if information is a real physical thing,
link |
what would its signatures be in matter
link |
and how do we recognize those?
link |
And I think the ones that are most obvious
link |
are the ones I've already articulated.
link |
You have these objects that seem completely improbable
link |
for the universe to produce
link |
because the universe doesn't have the design
link |
of that object in the laws.
link |
So therefore an object had to evolve.
link |
We talk, we call it evolution,
link |
but it had to be produced by the universe
link |
that then had all of the possible tasks
link |
to make that object specified.
link |
I mean, there's some,
link |
like there's an engineering question here of,
link |
are there sensors we can create that can give us,
link |
can help us discover certain pockets
link |
of high assemblies aliens?
link |
Like, I mean, there is a hope
link |
setting dogs and chairs aside,
link |
there's a hope that visually we could detect,
link |
like, because our universe,
link |
I mean, at least the way we look at it now,
link |
like this three dimensional like space time,
link |
we can visually comprehend it.
link |
It's interesting to think like,
link |
if we got to hang out,
link |
if there's an alien in this room,
link |
like would we be able to detect it with our current sensors?
link |
Not the fancy kinds, but like web cam.
link |
Like say standing over there.
link |
Yeah, standing over there
link |
or maybe like in this carpet,
link |
see there's all these kinds of patterns, right?
link |
I don't know if this carpet is an alien.
link |
Well, so I see what you're saying.
link |
So assembly theory is pretty general.
link |
Like, I mean, we've been applying it to molecules
link |
because it makes sense to apply it to molecules,
link |
but it's supposed to explain life,
link |
like the physics of life.
link |
So it should explain the things in this room
link |
in addition to molecules.
link |
So I guess, and you can apply it to images and things.
link |
So I guess the idea you could explore
link |
is just looking at everything on planet earth
link |
in terms of its assembly structure
link |
and then looking for things
link |
that aren't part of our biological lineage.
link |
If they have high assembly, they might be aliens on earth.
link |
I mean, that is a very kind of rigorous
link |
computer vision question.
link |
Can we visually, is there a strong correlation
link |
between certain kind of high assembly objects
link |
when they get to the scale
link |
where they're visually observable
link |
and some, like when it's say projected onto a 2D plane,
link |
can we figure out something?
link |
I'm glad you brought up the computer vision point
link |
because for a while I had this kind of thought in my mind
link |
that we can't even see ourselves clearly.
link |
So one of the things,
link |
people are worried about artificial intelligence
link |
for a lot of reasons,
link |
but I think it's really fascinating
link |
because it's like the first time in history
link |
that we're building a system
link |
that can help us understand ourselves.
link |
So like, people talk about AI physics,
link |
but like, when I look at another person,
link |
I don't see them as a 4 billion year lineage,
link |
but that's what they are.
link |
And so is everything here, right?
link |
So imagine that we built artificial systems
link |
that could actually see that feature of us,
link |
what else would they see?
link |
And I think that's what you're asking.
link |
And I think that would be so cool.
link |
I want that to happen,
link |
but I think we're a little ways off from it, but yeah.
link |
We're going there, I hope.
link |
Okay, let me ask you, I apologize ahead of time,
link |
but let me ask you the internet question.
link |
So you're a physicist,
link |
you ask rigorous questions about the physics of existence
link |
and these models of high assembly objects.
link |
Now, when the internet would see an alien,
link |
they would ask two questions.
link |
One, can I eat it?
link |
And two, can I have sex with it?
link |
So, the internet is.
link |
All the existential questions,
link |
those are very important ones.
link |
The internet is very sophisticated.
link |
It really is, it's gotten our basal cognition pretty good.
link |
So you kind of mentioned that it's very difficult.
link |
It's possible that we may not be
link |
even able to communicate with it.
link |
Right, I think the internet has more hope than we do.
link |
Yeah, it's a hopeful place, yes.
link |
Do you think in terms of interacting
link |
on this very primal level of sharing resources,
link |
like what would aliens eat?
link |
What would we eat?
link |
Would we eat the same thing?
link |
Could we potentially eat each other?
link |
One person eats the other, or the aliens eat us.
link |
And the same thing with not sex in general,
link |
or reproduction, but genetically mixing stuff.
link |
Like, would we be able to mix genetic information?
link |
Maybe not genetic, but maybe information, right?
link |
And I think part of your question is like,
link |
so if you think of life as like this history
link |
of events that happen in the universe,
link |
like there's this question of like,
link |
how divergent are those histories, right?
link |
So when we get to the scale of technology,
link |
it's possible to imagine,
link |
although we can't even do it.
link |
Like imagine all the possible technologies
link |
that could exist in the universe.
link |
But if you think about all the possible chemistries,
link |
somehow that seems like a lower dimensional space
link |
and a lower set of possibilities.
link |
So it might be that like when we interact with aliens,
link |
we do have to go back to those more basal levels
link |
to figure out sort of what the map is, right?
link |
Like the sort of where we have a common history.
link |
We must have a common history somewhere in the universe,
link |
but in order to be able to actually interact
link |
in a meaningful way, you have to have some shared history.
link |
I mean, the reason we can exchange genetic information
link |
in each other's food or eat each other as food
link |
is because we have a shared history.
link |
So we have to find that shared history.
link |
We have to find the common ancestor
link |
in this causality map, the causality tree.
link |
Yes, and we have a last universal common ancestor
link |
for all life on earth, which I think is sort of the nexus
link |
of that causality map for life on earth.
link |
But the question is where would other aliens
link |
diverge on that map?
link |
That's really interesting.
link |
And I mean, so say there's a lot of aliens out there
link |
in the universe, each set of organisms
link |
will probably have like a number, you know,
link |
like Erdos number of like how far,
link |
like how far our common ancestor is.
link |
And so the closer the common ancestor, like it is on earth,
link |
the more likely we are to be able
link |
to have sexual reproduction.
link |
Well, it's like sort of like humans having common culture
link |
and languages, right?
link |
Yeah, it might take a lot of work though with an alien
link |
cause you really have to get over a language barrier.
link |
So it's communication, it's resources.
link |
I mean, it's all the whole,
link |
and I think tied into that is the questions
link |
of like who's going to harm who.
link |
And actually definitions of harm.
link |
And whether your parents approve,
link |
you know, all those kind of questions.
link |
Whether the common ancestor approves.
link |
Yeah, that's just very true.
link |
How many alien civilizations do you think are out there?
link |
I don't have intuition for that,
link |
which I have always thought was deeply intriguing.
link |
So, and part of this, I mean, I say it specifically
link |
as I don't have intuition for that
link |
because it's like one of those questions
link |
that you feel around for a while
link |
and you really just, you can't see it
link |
even though it might be right there.
link |
And in that sense, it's a little like
link |
the quantum to classical can transition.
link |
You're like really talking about
link |
two different kinds of physics.
link |
And I think that's kind of part of the problem.
link |
Once we understand the physics,
link |
that question might become more meaningful.
link |
But there's also this other issue,
link |
and this was really instilled on me
link |
by my mentor, Paul Davies, when I was a postdoc,
link |
because he always talks about how, you know,
link |
whether aliens are common or rare is kind of just,
link |
you know, it like, you know, it follows a wave of popularity
link |
and it just depends on like the mood of, you know,
link |
what the culture is at the time.
link |
And I always thought that was kind of
link |
an intriguing observation, but also there's this,
link |
you know, set of points about
link |
if you go by the observational evidence,
link |
which we're supposed to do as scientists, right?
link |
You know, we have evidence of us
link |
and one origin of life event from which we emerged.
link |
And people wanna make arguments
link |
that because that event was rapid
link |
or because there's other planets
link |
that have properties similar to ours,
link |
that that event should be common.
link |
But you actually can't reason on that
link |
because our existence observing that event
link |
is contingent on that event happening,
link |
which means it could have been completely improbable
link |
And Brandon Carter, like clearly articulated that
link |
in terms of anthropic arguments a few decades ago.
link |
So there is this kind of issue
link |
that we have to contend with dealing with life
link |
that's closer to home than we have to deal with
link |
with any other problems in physics,
link |
which we're talking about the physics of ourselves.
link |
And when you're asking about the origin of life event,
link |
that event happening in the universe,
link |
at least as like our existence is contingent on it.
link |
And so you can think about sort of fine tuning arguments
link |
So, but the sort of otter part of it is like,
link |
when I think about how likely it is,
link |
I think it's because we don't understand this mechanism yet
link |
about how information can be generated spontaneously
link |
that I like, cause I can't see that physics clearly yet,
link |
even though I have a lot of, you know,
link |
like some things around the space of it in my mind,
link |
I can't articulate how likely that process is.
link |
So my honest answer is, I don't know.
link |
And sometimes that feels like a cop out,
link |
but I feel like that's a more honest answer
link |
and a more meaningful way of making progress
link |
than what a lot of people wanna do, which is say,
link |
oh, well, we have a one in 10 chance of having
link |
on an exoplanet with Earth like properties
link |
because there's lots of Earth like planets out there
link |
and life happened fast on Earth.
link |
Well, so I have kind of a follow up question,
link |
but as a side comment, what I really am enjoying
link |
about the way you're talking about human beings
link |
is you always say, and not to make yourself conscious
link |
about it, cause I really, really enjoy it.
link |
You say we, you don't say humans.
link |
You say, cause oftentimes like, you know,
link |
I don't know, evolutionary biologists
link |
will kind of put yourself out as an observer,
link |
but it's kind of fascinating to think that you as a human
link |
are struggling about your own origins.
link |
Yes, that's the problem.
link |
And yeah, and I think, I don't do that deliberately,
link |
but I do think that way.
link |
And this is sort of the inversion
link |
from the logic of physics because physics
link |
as it's always been constructed has treated us
link |
as external observers of the universe.
link |
And we are not part of the universe.
link |
And this is why the problem of life,
link |
I think demands completely new thinking
link |
because we have to think about ourselves
link |
as minds that exist in the universe
link |
and are at this particular moment in history
link |
and looking out at the things around us
link |
and trying to understand what we are inside the system,
link |
not outside the system.
link |
We don't have descriptions at a fundamental level
link |
that describe us as inside the system.
link |
And this was my problem with cellular automata also.
link |
You're always an external observer for a cellular automata.
link |
You're not in the system.
link |
What does the cellular automata look like from the inside?
link |
I think you just broke my brain with that question.
link |
But that's the fundamental.
link |
I thought about that for a long time, but.
link |
I'm gonna, yeah, that's a really clean formulation
link |
of a very fundamental question,
link |
because you can only, to understand cellular automata,
link |
you have to be inside of it.
link |
But as a human, sort of a poetic, romantic question,
link |
does it make you sad?
link |
Does it make you hopeful whether we're alone or not?
link |
Like in the different possible versions of that,
link |
if we're the highest assembly object in the entire universe,
link |
does that give you?
link |
At this moment in time, maybe.
link |
At this moment in the causal.
link |
Cause we may, I assume we have a future.
link |
Well, we definitely have a future.
link |
The question is where that future decreases the assembly.
link |
Like it could be where at the peak, or we could be just.
link |
That would be inconsistent with the physics in my mind.
link |
But so I should give a caveat.
link |
I've given the caveat that I'm biased as a physicist,
link |
but I'm also biased as an eternal optimist.
link |
So pretty much all of my modes of operation
link |
for building theories about the world
link |
are not like an Occam's razor,
link |
what's the simplest explanation,
link |
but what's the most optimistic explanation.
link |
And part of the reason for that
link |
is if you really think explanations have causal power,
link |
in the sense that our,
link |
like the fact that we have theories about the world
link |
has enabled technologies
link |
and physically transform the world around us.
link |
I think I have to take seriously that
link |
as a part of the physics I wanna describe
link |
and try to build theories of reality
link |
that are optimistic about what's coming next
link |
because the theories are in part
link |
the causes of what comes next.
link |
So there could be a physics of hope
link |
or physics of optimism in there too.
link |
Is that seems like also,
link |
I mean, optimism does seem to be a kind of engine
link |
that results in innovation.
link |
why the hell are we trying to come up with new stuff?
link |
Oh, so I made this point about thinking life
link |
is the physics of existence.
link |
And it's not just the physics of existence,
link |
it's the physics of more things existing.
link |
So I think one of these drives of like.
link |
Yeah, creativity, like optimism.
link |
So if you like, people like entropy.
link |
I don't like entropy as it was formulated in the 1800s.
link |
I think it's an antiquated concept,
link |
but this idea of maximizing
link |
over the possible number of states that could exist.
link |
Imagine the universe is actually trying to maximize
link |
over the number of things that could physically exist.
link |
What would be the best way to do that?
link |
The best way to do that
link |
would be evolve intelligent technological things
link |
that could explore that space.
link |
So, okay, that's talking about alien life
link |
out there in the universe,
link |
but you've also earlier in the conversation mentioned
link |
the shadow biosphere.
link |
So is it possible that we have weird life here on earth
link |
that we're just not,
link |
like even in a high assembly formulation of life,
link |
that we're just not paying attention to?
link |
Like life we're potentially able to detect,
link |
but we're blind to.
link |
And maybe you could say, what is the shadow biosphere?
link |
Yeah, the shadow biosphere is this idea
link |
that there might've been other original life events
link |
that happened on earth that were independent
link |
from the original life event that led to us
link |
and all of the life that we know on earth.
link |
And therefore there could be aliens
link |
in the sense they have a different origin event.
link |
And it was proposed by a number of people,
link |
but one of them was Paul Davies
link |
that I mentioned earlier is my mentor.
link |
And he has a really cute way of saying
link |
that aliens could be right under our noses
link |
or even in our noses.
link |
With a British accent, it sounds better.
link |
But anyway, so the idea is like,
link |
it could literally be anywhere around us.
link |
And if you think actually about the discovery
link |
of like viruses and bacteria,
link |
for a long time they were kind of a shadow biosphere.
link |
It was life that was around us, but invisible.
link |
But this takes it a little bit further
link |
and saying that all of those examples,
link |
viruses, bacteria and everything that we've discovered so far
link |
has this common ancestry
link |
and the last universal common ancestor of life on earth.
link |
So maybe there was a different origin event
link |
and that life is weirder still and might be among us
link |
and we could find it.
link |
We don't have to go out and the stars look for aliens
link |
just here on earth.
link |
Do you think that's a serious possibility
link |
that we should explore with the tools of science?
link |
Like this should be a serious effort.
link |
I think yes and no.
link |
And I mean, yes, because I think it's a serious hypothesis
link |
and I think it's worth exploring.
link |
And it is certainly more economical
link |
to look for signs of alien life on earth
link |
than it is to go and build spacecraft
link |
and send robots to other planets.
link |
And that was one of the reasons it was proposed is,
link |
well, if we do find an example of another original life
link |
on earth, it's hugely informative
link |
because it means the origin of life is not a rare event.
link |
If it happened twice on the same planet,
link |
that means it's probably pretty probable
link |
given conditions are right.
link |
So it has huge potential scientific impact,
link |
not to mention the fact that you might have like biochemistry
link |
and stuff that's informative for like medicine
link |
and stuff like that.
link |
But I think the thing for me that's challenging about it
link |
and this really comes from my own work,
link |
like thinking about life as a planetary scale process
link |
and also trying to understand
link |
sometimes what I call like the statistical mechanics
link |
of biochemistry, but large scale statistical patterns
link |
in the chemistry that life uses on earth.
link |
There are a lot of regularities there
link |
and life does seem to have planetary scale organization
link |
that's consistent even with some of the patterns
link |
that we see at the individual scale.
link |
So if you think life is a planetary scale phenomenon
link |
and the chemistry of life has to be sort of not just,
link |
it's not, an individual is not necessarily
link |
the fundamental unit of life, right?
link |
The fundamental unit of life
link |
is these informational lineages and they're kind of,
link |
they intersect over spatial scales.
link |
So everything on earth is kind of related
link |
by the common causal history.
link |
So it's hard for me based on the way I think
link |
about the physics and also some of the stuff
link |
that my group has done to really think
link |
that there could be evidence
link |
or there could be a second sample of life on earth.
link |
But I think there are ways
link |
that we need to be more concrete about that.
link |
And I have thought a little bit about like,
link |
like you can represent the chemistry
link |
in an individual cell as a network.
link |
And then those networks, something my group has shown
link |
actually scale with the same property.
link |
So ecosystems have the same properties
link |
as individuals as planetary scale.
link |
And then you could imagine
link |
if you had alien chemistry intermixed in there,
link |
that scaling would be broken.
link |
So if there's some robustness property
link |
or something associated to it,
link |
and you get alien chemistry in there,
link |
it just breaks everything.
link |
And you don't have a planetary ecosystem functioning
link |
and individuals functioning across all these scales.
link |
So I guess what I'm arguing
link |
is life is not a scale dependent phenomenon.
link |
It's not just cellular life.
link |
So if you have a shadow biosphere,
link |
it has to be integrated with all of these other scales.
link |
And that would lose the meaning
link |
of the word shadow biosphere, I guess.
link |
So it's an open question, right?
link |
And I think it would tell us a lot.
link |
So there has been very minimal effort
link |
of people to look for a shadow biosphere.
link |
But then the question,
link |
it could be possible that there's like
link |
sufficiently distinct planets within one planet,
link |
meaning like environments within one planet.
link |
Like, I don't know.
link |
I've been looking recently
link |
because of having a chat with Catherine Duclair
link |
about Io, the moon of Jupiter,
link |
that's like all volcanoes and volcanoes are bad ass.
link |
But like, imagining life inside volcanoes, right?
link |
It seems like sufficiently chemically different
link |
like to be living in the darkness
link |
where there's a lot of heat
link |
and maybe you could have different Earths on a planet.
link |
Or like if you go deep enough in the crust,
link |
maybe there's like a layer where there's no life.
link |
And then there's suddenly life again.
link |
And maybe those, you know, lizard men
link |
or whatever they are that people dream about
link |
are really down there.
link |
I know that's a little flippant,
link |
but really like there could be like chemical cycles
link |
deep in the Earth's crust that might be alive
link |
and are completely distinct
link |
in chemical origin to surface life.
link |
Right, that they wouldn't be interacting with each other.
link |
Yeah, and that's one of the proposals
link |
for the shadow biosphere is like,
link |
sometimes people talk about it as being geologically
link |
or geographically distinct that it might be,
link |
you know, you have no life for this region
link |
and then a different example.
link |
And then sometimes people talk about it
link |
being chemically distinct,
link |
that the chemistry is sufficiently different,
link |
that it's completely orthogonal
link |
or non interacting with our chemistry.
link |
It seems to me at least the chemistry
link |
is a more powerful boundary than geographic.
link |
It just seems like life finds a way literally to travel.
link |
What do you think about all these UFO sightings?
link |
So to me, it's really inspiring.
link |
It's yet another localized way to dream
link |
about the mysterious that is out there.
link |
Yeah, so I've actually been more intrigued
link |
by the cultural phenomena UFOs
link |
than the phenomena UFOs themselves,
link |
because I think it's intriguing about how
link |
we are preparing ourselves mentally
link |
for understanding others
link |
and how we have thought about that historically
link |
and what the sort of modern incarnations of that are.
link |
It's more like, I want an explanation for us.
link |
That's my motivation.
link |
And having some, you know,
link |
streaks across the sky or something
link |
and saying that's aliens,
link |
it doesn't tell you anything.
link |
So unless you have a deeper explanation
link |
and you have, you know, more lines of,
link |
you know, where is this gonna take us in the future?
link |
It's just not as interesting to me
link |
as the problem of understanding life itself
link |
and aliens as a more general phenomenon.
link |
I do think it's, just as you said,
link |
a good way to psychologically and sociologically
link |
prepare ourselves to sort of like,
link |
what would that look like?
link |
And very importantly,
link |
which is what a lot of people talk about politically,
link |
sort of there's this idea from the,
link |
so I came from the Soviet Union of like the Cold War
link |
and we have to hide secrets.
link |
There's some way in us searching for life on other planets
link |
or our searching for life in general,
link |
the way we've done government in the past,
link |
we tend to think of all new things
link |
as potential military secrets,
link |
so we want to hide them.
link |
And one of the ways that people kind of look
link |
at UFO sightings is like,
link |
like maybe we shouldn't hide this stuff.
link |
Like what is the government hiding?
link |
I think that's a really, you know,
link |
in one sense it's a conspiratorial question,
link |
but I think in another,
link |
it's an inspiration to change the way we do government
link |
to where secrets don't,
link |
maybe there are times when you want to keep secrets
link |
as military secrets,
link |
but maybe we need to release a lot more stuff
link |
and see us as a human species as together
link |
in this whole search.
link |
Yeah, the public engagement part there
link |
is really interesting.
link |
And it's almost like a challenge
link |
to the way we've done stuff in the past
link |
in terms of keeping secrets when they're not,
link |
so like the first step,
link |
if you don't know how something works,
link |
if there's a mysterious thing,
link |
the first instinct should not be like, let's hide it.
link |
Let's put it in the closet.
link |
So that the Chinese or the Russian government
link |
or whatever government doesn't find it.
link |
Maybe the first instinct should be, let's understand it.
link |
Perhaps let's understand it together.
link |
No, I think that's good.
link |
And something I realized recently
link |
that I never thought was gonna be a problem,
link |
but I think this actually helps with quite a bit
link |
is because so many people nowadays
link |
believe we've already made contact,
link |
that as an astrobiologist,
link |
if we actually want to understand life and make contact,
link |
we kind of have to deconstruct the narratives
link |
we've already built from ourselves
link |
and kind of unteach ourselves
link |
that we've learned about aliens and then reteach ourselves.
link |
So there's this really interesting sort of dialogue there
link |
and making it open to the public
link |
that they actually have to think critically about it
link |
and they see the evidence for themselves,
link |
I think is really important for that process.
link |
Yeah, that aliens might be way weirder than we can imagine.
link |
Yes, I'm pretty sure they're probably weirder
link |
than we can imagine.
link |
Okay, we've in 2020 and still living through a pandemic,
link |
setting the political and all those kinds of things aside,
link |
I've always found viruses fascinating
link |
as dynamical systems, I was gonna say living systems,
link |
but I've always kind of thought of them as living,
link |
but that's a whole nother kind of discussion.
link |
Maybe it'd be great to put that on the table.
link |
One, do you find viruses beautiful slash terrifying?
link |
And two, do you think they're living things
link |
or there's some aspect to them per our discussion of life
link |
that makes them living?
link |
I mean, living in a pandemic saying viruses are beautiful
link |
is probably a hard thing,
link |
but I do find them beautiful to a degree.
link |
I think even in the sense of mediating a global pandemic,
link |
there's something like deeply intriguing there
link |
because these are tiny, tiny little things, right?
link |
And yet they can essentially cause a seizure
link |
or handicap an entire civilization at a global scale.
link |
So just that intersection between
link |
our perceived invincibility and our susceptibility to things
link |
and also the interaction across scales of those things
link |
is just a really amazing feature of our world.
link |
Most technology, whether it's viruses or AI
link |
that can scale in an exponential way,
link |
like kind of run as opposed to like,
link |
one thing makes another thing makes another thing,
link |
it's one thing makes two things
link |
and those two things make four things.
link |
Like that kind of process
link |
also seems to be fundamental to life.
link |
And it's terrifying because in a matter of,
link |
in a very short time scale, it can,
link |
if it's good at being life, whatever that is,
link |
it can quickly overtake the other competing forms of life.
link |
And that's scary both for AI and for viruses.
link |
And it seems like understanding these processes
link |
that are underlying viruses.
link |
And I don't mean like on the virology or biology side,
link |
but on some kind of more computational physics perspective
link |
as we've been talking about,
link |
seems to be really important to figure out
link |
how humans can survive.
link |
Along with this kind of life
link |
and perhaps becoming a multi planetary species
link |
is a part of that.
link |
Like there's no, maybe like we'll figure out
link |
from a physics perspective is like,
link |
there's no way any living system
link |
can be stable for prolonged period of time
link |
and survive unless it expands exponentially throughout.
link |
Like we have to multiply.
link |
Otherwise anything that doesn't multiply exponentially
link |
will die eventually.
link |
Maybe that's a fundamental law.
link |
Maybe, I don't know.
link |
I always get really bothered by these Darwinian narratives
link |
that are like the fittest replicator wins and things.
link |
And I don't, I just don't feel like
link |
that's exactly what's going on.
link |
I think like the copying of information
link |
is sort of ancillary to this other process of creativity.
link |
Right, so like the drive is actually,
link |
the drive is creativity,
link |
but if you wanna keep the creativity
link |
that's existed in the past,
link |
it has to be copied into the future.
link |
So replication, like if you, so that for me is,
link |
so I had this set of arguments with Michael Lockman
link |
and Lee Cronin about the like life being about persistence.
link |
They thought it was about persistence
link |
and like survival of the fittest kind of thing.
link |
And I'm like, no, it's about existence.
link |
It's like, cause when you're talking about that,
link |
it's easy to say that in retrospect,
link |
you can post select on the things that survived
link |
and then say why they survived,
link |
but you can't do that going forward.
link |
That's really profound
link |
that survival is just a nice little side effect feature
link |
of maximizing creativity, but it doesn't need to be there.
link |
Yeah, I like that. That's really beautiful.
link |
Yeah, I know, like I said, I like optimistic theories.
link |
Well, I don't know if that's optimistic.
link |
That could be terrifying to people because,
link |
because a system that maximizes creativity
link |
may very quickly get rid of humans for some reason,
link |
if it comes up with some other creative,
link |
I mean, forms of existence, right?
link |
This is the AI thing is like the moment you have an AI system
link |
that can flourish in the space of ideas
link |
or in some other space much more effectively than humans.
link |
And it's sufficiently integrated into the physical space
link |
to be able to modify the environment.
link |
I think we'll just be like
link |
the core genetic architecture or something.
link |
We'll be like the DNA for AI, right?
link |
It's like, we haven't lost the past informational
link |
architectures on this planet.
link |
They're still there.
link |
Yeah, so the AI will use our brains in some part
link |
to like ride, like accelerate the exchange of ideas.
link |
That's the neural language dream is that,
link |
well, the humans will be still around
link |
because you're saying architecture.
link |
Yeah, but I don't even think
link |
they necessarily need to tap into our brains.
link |
I mean, just collectively, we do interesting things.
link |
What if they were just using like the patterns
link |
in our communication or something?
link |
Oh, without controlling it, just observing?
link |
Well, I don't know.
link |
In what sense do you control the chemistry
link |
happening in your body?
link |
I mean, obviously I don't know.
link |
I'm just, like the way I look at, like people look at AI
link |
and then they look at this thing that's bigger than us
link |
and is coming in the future and is smarter than us.
link |
And I think though that looking at the past history
link |
of life on the planet and what information
link |
has been doing for the last 4 billion years
link |
is probably very informative to asking questions
link |
about what's coming next.
link |
one is planetary scale transitions are really important
link |
So the global internet and sort of global integration
link |
of our technology, I think is an important thing.
link |
So that's again, life is a planetary scale phenomenon
link |
but we're an integrated component of that phenomenon.
link |
I don't really see that the technology
link |
is gonna replace us in that way.
link |
It's just gonna keep scaffolding and building.
link |
And I also don't have an idea
link |
that we're gonna build AI in a box.
link |
I think AI is gonna emerge.
link |
AGI to me is a planetary scale phenomena
link |
that's gonna emerge from our technology.
link |
Planetary scale phenomena.
link |
But do you think an AGI is not distinct from humans?
link |
The whole package.
link |
The whole package, yeah.
link |
Comes as a planetary scale phenomena.
link |
And that goes back to the fact that like,
link |
you were asking questions about you as an individual.
link |
Like, what are you as an individual?
link |
You're like a packet of information
link |
that exists in the particular physical thing that is you.
link |
We're all just packets of information.
link |
And some of us are aggregates in certain ways
link |
but it's all just kind of exchanging
link |
and propagating, right?
link |
Is your packet of information
link |
that you've continually referred to as Sarah
link |
afraid of the dissipation of the death of that packet?
link |
Are you afraid of death?
link |
Do you ponder death?
link |
Does death have meaning in this process
link |
I think I have the natural biological urge
link |
that everyone has to fear death.
link |
I think the thing that I think is interesting
link |
is if I think about it rationally,
link |
I'm not necessarily afraid of death for me
link |
because I won't be aware of being dead.
link |
But I am afraid like for my kids
link |
because it matters to them if I die.
link |
So again, like I think death becomes more significant
link |
as a collective property, not as an individual one.
link |
Yeah, but isn't there something to fear
link |
about the fact that the way,
link |
like the creative,
link |
the complexity of information
link |
that's been like created in you.
link |
The fact that it kind of breaks apart and disappears.
link |
It doesn't, but I don't think it disappears.
link |
It's just not me anymore.
link |
Right, but that process of it being not you anymore,
link |
that doesn't scare you?
link |
Of course it does.
link |
The mystery of it.
link |
Yeah, but I guess I'm heartened by the fact
link |
that there will be some imprints of the fact
link |
that I existed still in the universe after I leave it.
link |
Yeah, but there'll be a...
link |
And also that has to do with my perception of time, right?
link |
So, I perceive time as flowing,
link |
but that might not be the case.
link |
I mean, this is standard physicist comfort is,
link |
every moment exists and there's no...
link |
And the flow of time is just our perception of us changing.
link |
So, you can travel back in time and that's comforting?
link |
Like from a physicist's concept?
link |
I'm not talking about traveling back in time.
link |
I'm just saying that the moments in the past still exist.
link |
Now, whether the moments in the future exist or not
link |
is a different question.
link |
That's not comforting to me in terms of death.
link |
The flow of time is not...
link |
I think there's no comfort in the face of death
link |
for what we are because we like existing.
link |
And I think it's especially true if you love life
link |
and you love what life is.
link |
Do you think there's a certain sense in which
link |
the fear of death or the fear of nonexistence,
link |
maybe fear is not the right word,
link |
is the actual very phenomena that gives birth to existence?
link |
Like, death is fundamental.
link |
It just feels like freaking out, oh shit,
link |
this ride ends is actually like the...
link |
That's the thing that gives birth to this whole thing.
link |
That like, it's constantly...
link |
It's matter constantly freaking out about the fact
link |
that it's gonna be the most.
link |
No, I think things like to exist.
link |
I think they wanna exist.
link |
Yeah, there's a desire, whatever, to exist.
link |
There's a drive to exist
link |
and there's a drive for more things to exist.
link |
I guess, yeah, I like existing.
link |
I like it a lot and I don't know it any other way.
link |
See, I don't even know if I like existing.
link |
I think I really don't like not existing.
link |
Yeah, that's true.
link |
Yeah, maybe it's that.
link |
Some days I might like existing less than others.
link |
Yes, but like, I think those are like surface feelings.
link |
It seems like there's something fundamental
link |
about wanting to exist.
link |
No, I think that's right.
link |
But I think to your point that that might go back
link |
to the more fundamental idea that, you know,
link |
if life is the physics of existence
link |
and maximizing existence, individual organisms,
link |
of course, wanna maximize their existence
link |
and everything, you know, like wants to exist.
link |
But I guess for me, the small comfort is
link |
my existence matters to future existence.
link |
Speaking of future existence, is there advice
link |
you can give to future pockets of existences,
link |
AKA young people, about life?
link |
You've had, you've worn many hats.
link |
You've taken on some of the biggest problems
link |
Is there advice you can give to young people
link |
about life, about career, about existing?
link |
Yeah, maybe not about the last one.
link |
You know, a lot of people ask me this question
link |
about like working on such hard problems,
link |
like how can you make a successful career out of that?
link |
But I think for me, it couldn't be otherwise.
link |
Like I have to, to be fulfilled,
link |
you have to work on things you care about.
link |
And that's always kind of driven me.
link |
And that's been discipline, department,
link |
and sort of superficial level problem independent
link |
because I started at community college actually,
link |
and I was taking a physics class
link |
and I learned about magnetic monopoles
link |
and we didn't know if they existed in the universe,
link |
but we could predict them and we could go look for them.
link |
And I was so deeply intrigued by this idea
link |
that we had this mathematical formula to go look for things.
link |
And then I wanted to become a theoretical physicist
link |
But that actually wasn't my driving question.
link |
I realized my driving question is the nature
link |
of the correspondence between our minds
link |
and physical reality and what we are.
link |
And that question is very deep,
link |
so you can work across a lot of fields doing that.
link |
But I think without that driving question,
link |
I never would have been able to do all the things
link |
It's really the passion that drives it.
link |
And usually when students ask me these kinds of questions,
link |
I tell them like, you have to find something
link |
you really care about working on
link |
because if you don't really care about it,
link |
A, you're not gonna be your best at it,
link |
and B, it's not gonna be worth your time.
link |
Why would you spend your time working on something
link |
you're not interested in?
link |
So find the driving questions.
link |
Yeah, find the driving question.
link |
Find your passion.
link |
I mean, I think passion makes a huge difference
link |
in terms of creativity, talent, and potential,
link |
and also being able to tolerate all the hard things
link |
that come with any career or life.
link |
Yeah, I've had a bunch of moments in my life
link |
where I've just been captivated
link |
by some beautiful phenomena.
link |
And I guess being rigorous about it
link |
and asking what is the question underlying this phenomena,
link |
like robots bring a smile to my face
link |
and forming a question of like,
link |
why the hell is this so fascinating?
link |
Why is this, specifically the human robot
link |
interaction question that something beautiful
link |
is brought to life when humans and robots interact,
link |
understanding that deeply.
link |
It's like, okay, so this is gonna be my life work then.
link |
I don't know what the hell it is,
link |
but that's what I wanna do.
link |
And doing that for whatever the hell gives you
link |
that kind of feeling, I guess, is the point.
link |
Am I allowed to ask you a question?
link |
because I had this colleague that suggested the idea
link |
that consciousness might be contagious.
link |
And so interacting with things,
link |
it's an interesting idea, right?
link |
So I'm wondering sort of the motivation there.
link |
Is it the motivation that you want more of the universe
link |
to appreciate things the way we do
link |
and appreciate those interactions?
link |
Or is it really more the enjoyment of the human
link |
in those interactions?
link |
Like, is it, do you know what I'm asking?
link |
See, I think consciousness is created
link |
in the interaction between things.
link |
So the joy is in the creation of consciousness.
link |
I really like the idea that
link |
it doesn't just have to be two humans
link |
creating consciousness together.
link |
It could be humans and other entities.
link |
We talked offline about dogs and other pets and so on.
link |
There's a magic, I mean, I've been calling it love.
link |
It's this beauty of the human experience that's created.
link |
And it just feels like fascinating that you could do that
link |
with a robotic system.
link |
And there's something really powerful, at least to me,
link |
about engineering systems that allow you
link |
to create some of the magic of the human experience.
link |
Cause then you get to understand what it takes,
link |
at least get inklings of what it takes
link |
to create consciousness.
link |
And I don't get this, you know,
link |
philosophers get really upset about this idea
link |
that sort of the illusion of consciousness is consciousness.
link |
But I really liked the idea of engineering systems
link |
that fool you into thinking they're conscious.
link |
Because that's sufficient to create the magical experience.
link |
Right, because it's the interaction, yeah.
link |
It's the interaction, yeah.
link |
And this is the Russian hat I wear,
link |
which is like, I think there's an ocean of loneliness
link |
I think we're deeply lonely.
link |
We're not even allowing ourselves to acknowledge that.
link |
And I kind of think that's what love is between romantic love
link |
and friendship is two people kind of getting a little bit
link |
like alleviating for brief moment.
link |
That loneliness, but not, but we're not there.
link |
It's not the full aspect of that loneliness.
link |
Like we're desperately alone.
link |
We're desperately afraid of nonexisting.
link |
I have that kind of sense.
link |
And I just want to explore that ocean of loneliness more.
link |
When engineering, like create a submarine
link |
that goes into the depth of that loneliness.
link |
So creating systems that can truly hear you.
link |
Make the universe a less lonely place.
link |
Let me ask you about the meaning.
link |
You've brought up why.
link |
The physics of why.
link |
What do you think is the meaning of our particular planets,
link |
set of existences and the universe in general?
link |
The meaning of life.
link |
Someone once told me as a physicist,
link |
I'm not allowed to ask why questions,
link |
but I don't believe that.
link |
So I think what we are is the creative process
link |
in the universe, I think.
link |
And for me, that's the meaning.
link |
The ability to create more possibilities
link |
and more things to exist.
link |
What is, Dostoevsky has the saying,
link |
beauty will save the world.
link |
What is, is there a connection between creation and beauty?
link |
So is that like, is beauty a correlate of creation?
link |
I mean, why is it, you know,
link |
a lot of people have asked these kinds of questions,
link |
but like, why is it we have such an emotional response
link |
to intellectual activity or creativity?
link |
And that seems kind of a deep question to me.
link |
Like, it seems very intrinsic to what we are.
link |
So I do have an interest in the questions I ask
link |
because I think they're beautiful
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and I think the universe is beautiful.
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And I'm just so deeply fascinated
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by the fact that I exist at all.
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And so maybe it's that, you know,
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that intrinsic feeling of beauty
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that's in part driving, you know,
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the physics of creating more things.
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So they could be deeply related in that way.
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Well, I don't think there's a better way to end it.
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I think this conversation was beautiful.
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Thank you so much for wasting
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all your valuable time with me today.
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I really, really appreciate it, Sarah.
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I hope we get the chance to talk again.
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I hope, like I mentioned to you offline,
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we get a chance to talk with Lee.
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You guys have a beautiful, like, intellectual chemistry
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that's fascinating to listen to.
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So I'm a huge fan of both of you
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and I can't wait to see what you do next.
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Thanks for listening to this conversation
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with Sarah Walker and thank you to Athletic Greens,
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Nat Sweet, Blinkist, and Magic Spoon.
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Check them out in the description to support this podcast.
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And now let me leave you with some words
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from Robert Frost, one of my favorite poets.
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In three words, I can sum up everything
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I've learned about life.
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Thank you for listening.
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I hope to see you next time.