Blaise Agüera y Arcas: uncertainty

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…ut, but hopefully we'll we'll set up the problem in in a perhaps somewhat new way that that I I hope will help to do that. And finally, in section c, how is life related to mind, machines and culture? If I have time, I will get into this as well and talk a bit about the emergence of intelligence and mind in an artificial living system and, the influence of machines on the next major evolutionary transition of life. So, you know, it was really cool to to read this paper from 2020 and to see how much of the perspective, that that, that you had already been exploring then, you know, feels, you know, right and consistent with, you know, with with a sort of fresh look at this at these problems in 2025. Let me just begin with, with this question of souls. It used to be in the nineteenth century and and earlier, that we thought that, life had some vital force or spirit, that animated it and made it different from inanimate matter. In the nineteenth century, when we began to figure out organic chemistry and be able to synthesize urea and so on, the the idea that that no, we should really adopt a strictly materialist perspective because there's nothing special or different about the matter in us versus the matter anywhere else in the universe, took hold. And that's progress for sure, but, but it also, you know, when we when we embrace atoms and materialism fully, we're left with some, some questions about, you know, what differentiates life from non life then. You know, like, what can we even say about life? There are at least some biologists who who say, well, maybe it's not even meaningful to talk about about any difference between life and non life. But I I don't think that that's true. And I think that the answer to the to the conundrum is to invoke function. Function is the thing that life has, that non life doesn't have. In other words, if we, you know, just to to give you a little parable, if I were to come back from the future with this object and you ask me what it is, and I tell you it is an artificial kidney with 100 year lifespan. You can implant it in a body and it'll it'll, you know, it'll work the way your kidneys do. It'll it'll filter urea from the blood and so on. That's a really important piece of information, but it's not a material or a materialist piece of information. It's not something that you could read off from the atoms. And, you know, those atoms could be, I don't know, tungsten filaments or carbon nanotubes are made out of some technology we don't understand now, or it could be organic, it could be made out of cloned tissue. And and the point is that it working as a kidney doesn't depend on that matter. There is a kind of separation of concerns between the matter and the function. And so there's some real sense in which the function is like a spirit or like something like something immaterial, it's not material, and yet it also relies of course on the physics of what's going on. You can't have the spirit without the matter as it were. So function is really important and, and function is something that, you know, a rock on a non living planet, somewhere doesn't have. going on. You can't have the spirit without the matter as it were. So function is really important and, and function is something that, you know, a rock on a non living planet, somewhere doesn't have. You know, if you if you break a rock on a non living planet, you now have 2 rocks. You don't have a broken rock. If you break a kidney, you now no longer have a working kidney. That's the difference between something functional and something non functional. This idea of function was formalized by Alan Turing, who never intended the Turing machine to actually be built, when he wrote it in 1936, but there is 1 that was built by Mike Davy in 2010. I don't need to review Turing machines with all of you, of course. You you all know how they how they work. But I do want to review briefly von Neumann's update to Turing's thinking about computation, which which he did a few years later. This was published posthumously after von Neumann died. But the idea behind behind von Neumann's thinking is he was trying to answer the same question that Schrodinger had quite had asked in his What is Life book? And in particular, he was trying to ask the question, if you have a robot that is swimming around, on a, you know, in a in a pond and the pond has lots of loose Legos around. There were no I don't know if there were Legos in 1950, but let's pretend there were Legos in 1950. And the job of the robot is to assemble those Legos into a new robot like itself. You know, there's something a little bit mysterious about that. It feels a little bit like pulling yourself up by your own bootstraps or like a paradox. And so he asked, what does it take for something to be able to make something like itself? Which seems, hard, almost paradoxical. And his conclusion was, well, you need to have instructions for how to make a mi. You need to have a tape with instructions for how to make a mi, and you need to have a universal constructor that will follow the, the instructions on that on that tape in order to assemble the necessary parts. You also need to have a tape copier, so that you can give your offspring, another copy of that tape. By the way, the tape has to also include the instructions for making the universal constructor and the tape copier. If those things all hold, then you have life. You have something that can build itself. And, what's what's so profound about about von Neumann's insight, I mean, first of all, he predicted all of this before we knew the structure and function of DNA, before we we understood what ribosomes were or discovered DNA polymerase. So he called it exactly right. Those all of those things really do exist, inside cells and he figured this out from pure theory, never having set foot in a bio lab. The the profound insight is that he said, by the way, a universal constructor is a universal Turing machine. Those are literally 1 and the same thing. And by by making that observation, what he discovered was that life is literally embodied computation. It is computational. You cannot have life without having computation. So obviously not everything that is alive reproduces, but everything that is alive has to be able to make itself. ied computation. It is computational. You cannot have life without having computation. So obviously not everything that is alive reproduces, but everything that is alive has to be able to make itself. It has to be able to do some combination of healing, growing, maintaining itself, reproducing. All of that is autopoiesis. All of that involves self construction and all of that necessarily involves a universal constructor. Now, what do I mean by embodied computation? This is a really important distinction between Von Neumann and Turing. In Turing, the symbols that the that the head writes are different from the head itself and the tape and, and the table of rules that the that the head follows. Whereas in von Neumann, it's it's more like a 3 d printer. The the memory is atoms, not abstract symbols. In other words, you know, you could think about a Turing machine as like this laptop, you know, which can't extrude another laptop out the side. But a von Neumann replicator is like a combination of a laptop and a 3 d printer that can print another laptop. So its memory is actually atoms. That's what I mean by embodied. So I don't mean embodied in the ways that a lot of roboticists talk about embodied. I mean that that there is a closure between the the medium in which the computation happens and the thing that is actually doing the computation. That's the key. So computation that is embodied in that sense and that is autopoietic is alive. You can't reproduce non trivially, evolvably without without computation. No computation, no life. I do wanna say a word briefly about what I mean by computation and in this I'm following the the work of, Susan Stepney, Dominic Horseman, Rob Wagner, Viv Kendon. This is from a nice paper they wrote in 2023 relating, the evolution of a physical system and the computation that it does. So, you know, on top you have logical gates, on the bottom you have, you know, transistors in your computer. This is important because, you know, there's there are no bits in a computer, there are just voltages that go up and down. In fact, even the voltages are an abstraction of something further, you know, if we go further down. But, you know, the the point is that you have to coarse grain those voltages into bits and then you have to have a logical machine that talks about how those bits evolve, what are the what are the what are the computational processes that those bits undergo, and there's a mapping from the physical system to the logical system and vice versa. When we say something computes, what we mean is that it is possible to construct such a mapping and that therefore as the physical system evolves, that is equivalent to the logical system evolving. So, you know, there are some caveats. You can have stochastic computation in which there's a little bit of randomness injected so it doesn't have to be fully deterministic. Another really important caveat is that you don't want that description to be infinitely complex. Otherwise, you could have the trivial case of saying like, you know, the water in the SEN is a computer and the longer my computation, I just need to make my description longer and longer in order to match. No.…

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