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Is life a form of computation?

thereader.mitpress.mit.edu

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Re: Is life a form of computation?

#52

Earlier quoted context omitted.

Evolution is not optimizing anything. What's happening in the biosphere is a process of mutation & selection, it's not optimization towards any particular goal or objective. Furthermore & slightly more abstractly, b/c of conservation of mass & energy, what's actually happening is re-organization of existing biomass into different life forms enabled by solar radiation.

I suppose I fail to see why evolution through natural selection is not optimizing. That was Darwin's big idea, right? That given heredity, selection, and variation you end up with life forms we'd consider optimized for their environments? Or do you mean that optimization by definition must include intent, and evolution as a mindless process has no intentionality? I'm just not sure what you're driving at.

Optimization is by definition with respect to some cost function or goal. Evolution has none. Evolution happens, but has no goal.

Re: Is life a form of computation?

#53
Surprised the article didn't mention the most fitting sense in which life is computation, which is at the biosphere level. Life can be characterized as a (recursive) search function executing continuously over billions of years. It seeks out new environments, reacts to changes in the environment at all scales between molecules and mountains. Life is a vast, distributed visitor pattern whose payload is itself.

Re: Is life a form of computation?

#54

I love thinking about life as computation. Cells are computers, enzymes are functions, ribosomes are compilers, nucleic acids are source code... Enzymes in particular are a lot like unix pipelines. An enzyme catalyzes its substrate's conversion into its product which is the substrate of another enzyme. When cells ingest glucose, it flows through the glycolysis metabolic pathway until it becomes pyruvate, and may be r…

You're one of those cats that provides a subtle reminder that Dr. Alan Kay (invented the tablet/Xerox ALTO interface) was first a biologist. Thank you for the enlightened smalltalk! (;3)

Re: Is life a form of computation?

#55

Earlier quoted context omitted.

I suppose I fail to see why evolution through natural selection is not optimizing. That was Darwin's big idea, right? That given heredity, selection, and variation you end up with life forms we'd consider optimized for their environments? Or do you mean that optimization by definition must include intent, and evolution as a mindless process has no intentionality? I'm just not sure what you're driving at.

Optimization is by definition with respect to some cost function or goal. Evolution has none. Evolution happens, but has no goal.

Ah! That makes sense. Thank you for explaining!

Re: Is life a form of computation?

#56
post #44

I'm not too impressed with this article since it doesn't really give a definition for computing, just picks a few similarities between what we see as computing (in the practical sense) and what cells do. It's a shame because there *has* been a lot of deep work done on what kind of computer life is. People often use the Chomsky Hierarchy ( https://en.wikipedia.org/wiki/Chomsky_hierarchy ) to define the different types…

This is the kind of evolved computer science that was going on when I was a teenager. Have an upvote eig!

My addition: it's funny for how much speculation we get in the, "hard cognitive science" (RIP) that in lieu of the big insights we get from Godel, Turing, Russell that many/most undergraduates and even post-graduates still haven't internalized Wittgenstein's work especially the Tractatus. I feel like it gets us to, "the questions you're asking about how life works and the questions about what is at the core of logic and mathematics (language) are definitely related but not in any of the fundamental ways you hope they are..."

For the uninitiated-- try reading the thing in one sitting. It takes about an hour:

https://wittgensteinproject.org/w/index.php/Tractatus_Logico...

Re: Is life a form of computation?

#57
post #10

This feels like the kind of popsci that's written for people who already agree with the author - there's nothing resembling an argument, or even a definition of "computation." There are nods to Church-Turing, but the leap from "every effectively calculable function is computable" to "life is a computation" is larger than anything you could fit in a book.

I felt reminded of Hofstadter's Goedel/Escher/Bach mysticism that somehow everything is recursion.

I might not be a strange loop but I am indeed strange.

Re: Is life a form of computation?

#59

Articles like this indicate we should lock down the definition of "computation" that meaningfully distinguishes computing machines from other physical phenomena - a computation is a process that maps symbols (or strings of symbols) to other symbols, obeying certain simple rules[1]. A computer is a machine that does computations. In that sense life is obviously not a computation: it makes some sense to view DNA as sym…

I think you may be forgetting about analog computers https://en.wikipedia.org/wiki/Analog_computer

I don't think they are. The things analog computers work on are still symbolic - we don't care about the length of the rod or what have you, we care about the thing the length of the rod represents.
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