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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?

#61

Post by da_chicken »

AIPedant wrote: post #29

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 don't think it's necessary to completely discard the idea. However, I do think it's important, at the end of it all, to ask: Okay, so what's the utility of this framework? What am I getting out of setting up my point of view this way?

I'm reminded of an old YouTube video [0] that I rewatched recently. That video is "Every Zelda is the Darkest Zelda." Topically, it's completely different. But in it Jacob Geller talks about how there are many videos with fan theories about Zelda games where they're talking about how messed up the game is. Except, that's their only point. If you frame the game in some way, it's really messed up. It doesn't extract any additional meaning, and textually it's not what's present. So you're going through all this decoding and framing, and at the end your conclusion is... nothing. The Mario characters represent the seven deadly sins? Well, that's messed up. That's maybe fun, but it's an empty analysis. It has no insight. No bite.

So, what's the result here other than: Well, that's neat. It's an interesting frame. But other than the thought to construct it, does it inform us of anything? Honestly, I'm not even sure it's really saying life is a form of programming. It seems equally likely it's saying programming is a form of biochemistry (which, honestly, makes more sense given the origins of programming). But even if that were so, what does that give us that we didn't already know? I'm going to bake a pie, so I guess I should learn Go? No, the idea feels descriptive rather than a synthesis. Like an analogy without the conclusion. The pie has no bite.

[0]: https://youtu.be/O2tXLsEUpaQ

Re: Is life a form of computation?

#62

Post by ants_everywhere »

lmm wrote: post #59
ants_everywhere wrote: post #50

Earlier quoted context omitted.

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.

analog computers don't generally compute by operating on symbols. For example see the classic video on fire control computers https://youtu.be/s1i-dnAH9Y4?t=496

OP's specific phrasing is that they "map symbols to symbols". Analog computers don't do that. Some can, but that's not their definition.

Turing machines et al. are a model of computation in mathematics. Humans do math by operating on symbols, so that's why that model operates on symbols. It's not an inherent part of the definition.

Re: Is life a form of computation?

#63

Post by zmgsabst »

matheusmoreira wrote: post #46
heavyset_go wrote: post #41

Earlier quoted context omitted.

I think the issue with this way of thinking is that humans think in abstractions. Abstractions don't really exist, they're a product of the human mind, but then we apply them to nature. Calling DNA code, comparing NNs and the brain, etc. But those abstractions fall apart when you look a little too deeply at what actually happens in nature. Is DNA code? Or is it more like a machine? Is it neither, or is it something e…

> When you look at the nature of DNA, it does more than simply act as code. > It can edit and self-modify, self-assemble, self-replicate, it can turn genes on and off Unless my knowledge of biology is very outdated or incomplete, all of those things you cited are done to DNA. They don't happen spontaneously. DNA doesn't self-replicate, a whole bunch of enzymes come and actively copy it. Genes don't spontaneously turn…

I think RNA (in particular, ribozymes) does those things.

But DNA is effectively separation of concerns: RNA systems evolved to RNA mediated systems with DNA as more inert and reliable storage and enzymes as more effective catalysts. Or so the RNA world hypothesis goes.

Re: Is life a form of computation?

#65

Post by matheusmoreira »

zmgsabst wrote: post #63
matheusmoreira wrote: post #46

Earlier quoted context omitted.

> When you look at the nature of DNA, it does more than simply act as code. > It can edit and self-modify, self-assemble, self-replicate, it can turn genes on and off Unless my knowledge of biology is very outdated or incomplete, all of those things you cited are done to DNA. They don't happen spontaneously. DNA doesn't self-replicate, a whole bunch of enzymes come and actively copy it. Genes don't spontaneously turn…

I think RNA (in particular, ribozymes) does those things. But DNA is effectively separation of concerns: RNA systems evolved to RNA mediated systems with DNA as more inert and reliable storage and enzymes as more effective catalysts. Or so the RNA world hypothesis goes.

> ribozymes

I learned something new today! Thank you.

It's impressive that RNA of all things can be folded in such a way that it also acts like an enzyme.

Re: Is life a form of computation?

#69

Post by AIPedant »

ants_everywhere wrote: post #62
lmm wrote: post #59

Earlier quoted context omitted.

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.

analog computers don't generally compute by operating on symbols. For example see the classic video on fire control computers https://youtu.be/s1i-dnAH9Y4?t=496 OP's specific phrasing is that they "map symbols to symbols". Analog computers don't do that. Some can, but that's not their definition. Turing machines et al. are a model of computation in mathematics. Humans do math by operating on symbols, so that's why th…

No, analog computers truly are symbolic. The simplest analog computer - the abacus - is obviously symbolic, and thus is also true for WW2 gun fire control computers, ball-and-shaft integrators, etc. They do not use inscriptions which is maybe where you're getting confused. But the turning of a differential gear to perform an addition is a symbolic operation: we are no more interested in the mechanics of the gear than we are the calligraphy of a written computation or the construction of an abacus bead, we are interested in the physical quantity that gear is symbolically representing.

Your comment is only true if you take an excessively reductive view of "symbol."

Re: Is life a form of computation?

#70

Post by heavyset_go »

matheusmoreira wrote: post #46
heavyset_go wrote: post #41

Earlier quoted context omitted.

I think the issue with this way of thinking is that humans think in abstractions. Abstractions don't really exist, they're a product of the human mind, but then we apply them to nature. Calling DNA code, comparing NNs and the brain, etc. But those abstractions fall apart when you look a little too deeply at what actually happens in nature. Is DNA code? Or is it more like a machine? Is it neither, or is it something e…

> When you look at the nature of DNA, it does more than simply act as code. > It can edit and self-modify, self-assemble, self-replicate, it can turn genes on and off Unless my knowledge of biology is very outdated or incomplete, all of those things you cited are done to DNA. They don't happen spontaneously. DNA doesn't self-replicate, a whole bunch of enzymes come and actively copy it. Genes don't spontaneously turn…

I'm thinking more of early RNA and DNA life, where ideas like the RNA-world might have happened and applied. RNA can assemble, replicate, and catalyze to form deoxynucleosides in a proto-DNA, without "outside" work needing to happen from enzymes/proteins/etc.

Similarly, RNA and DNA "machines" could have existed before cellular life, in which genetic material self-assembled, transferred genes horizontally/vertically, etc, blurring the lines between genes as "code" and something else.

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