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Computation as a universal and fundamental concept

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Re: Computation as a universal and fundamental concept

#91

Post by Diogenesian »

jibal wrote: post #86
andsoitis wrote: post #81

Earlier quoted context omitted.

Metaphysics operates one level up from physics or the sciences, asking what reality has to be like for anything, including the sciences, to be possible or meaningful at all.

I know what metaphysics is (and your description isn't accurate--science is a knowledge-producing method that doesn't depend on metaphysics in order to be meaningful), but that has nothing to do with my statement. And it's called "metaphysics" because Andronicus placed that volume after the "physics" volume when he organized Aristotle's writings.

Science absolutely does depend on metaphysics. Most famously: the validity of the scientific method is ultimately a metaphysical extension of our intuitions about inductive reasoning and causality. There is no scientific proof that the scientific method is valid. ("Our intuitions" is why I said metaphysics is tautologically the domain of humans. This is essentially Kant's philosophical legacy: science will describe what it does, but humans intuitively understand reality in ways that defy noncircular scientific description, and metaphysics must be invoked to have a rational and grounded discussion about these intuitions.)

Re: Computation as a universal and fundamental concept

#93

Post by SideQuark »

Maxatar wrote: post #5
sgt101 wrote: post #2

Computation has turned out to be a far more general concept than I think was imagined, up to the point that many computer scientists now seem to equate computation with the functioning of the universe. Recently it's been shown that there are real, physical processes which are undecidable (we cannot know if a latice of atoms has a spectral gap or not, we cannot determine if a specific particle in a fluid flow will rea…

>Recently it's been shown that there are real, physical processes which are undecidable I want to push back a bit on this claim along two dimensions. Imagine a physical Turing machine built out of atoms, gears, levers, and an electron parked on the read/write head and ask whether that electron ever crosses some fixed plane in space, which it does only when the machine enters its halt configuration. That's now a purel…

> … so there's a physical process that's undecidable.

No, since you cannot physically build a Turing Machine. A Turing machine requires infinite tape. Any physically realizable machine doesn’t have that, so has finite states, so is decidable: enumerate the states in finite time - it halts or repeats, so all programs on a finite state machine are decidable.

Your example is not an undecudable physical process.

Godel things also don’t apply: Godel theorems are about proof of this or that from within the same system. In logic one can prove such things from an outside system, then construct towers, avoiding Godel theorems. Godel theorems also require a model of integers including multiplication (without multiplication, such systems were proven complete and decidable). However the universe does not contain a model of integers, as the physical universe is not unbounded: relativity places a finite limit in spacetime on what can interact.

Mixing math as reality fails at these requirements.

Re: Computation as a universal and fundamental concept

#94

Post by jibal »

jibal wrote: post #86
andsoitis wrote: post #81

Earlier quoted context omitted.

Metaphysics operates one level up from physics or the sciences, asking what reality has to be like for anything, including the sciences, to be possible or meaningful at all.

I know what metaphysics is (and your description isn't accurate--science is a knowledge-producing method that doesn't depend on metaphysics in order to be meaningful), but that has nothing to do with my statement. And it's called "metaphysics" because Andronicus placed that volume after the "physics" volume when he organized Aristotle's writings.

I asked for proof of claims and I just get "it absolutely does" and a bunch more assertions, and word salad like "the validity of the scientific method is ultimately a metaphysical extension of our intuitions about inductive reasoning and causality" -- there's nothing "metaphysical" about it ... the scientific method is a disciplined application of an effective process of discovery. And '"Our intuitions" is why I said metaphysics is tautologically the domain of humans' is more word salad -- "tautologically" has no business in that sentence, and none of the rest of it makes any sense either. Humans have multiple domains, not just "the" domain. Metaphysics is a field of study that non humans capable of studying can also study. Metaphysical facts govern everything, not just humans. etc. I consider this sort of junk to border on bad faith ... it certainly isn't of any use to me, and I have no interest in engaging with it.

> There is no scientific proof that the scientific method is valid.

The scientific method is provably effective in a lawful world. That the scientific method isn't provably effective is because the world is not provably lawful ... it's logically possible for the "laws" of physics--which are simply regularities that we have discovered--to suddenly change, oscillate, be random, etc. But as long as they don't the scientific method works ... and we can't do better. (Not in this world, anyway ... in some other world there might be oracles (aka gods or bibles) that always have the right answer and we could simply query them. Of course, such oracles are also not provably correct.)

Re: Computation as a universal and fundamental concept

#95

Post by pilgrim0 »

kaashif wrote: post #57

I like how every time a new technology is invented and becomes big, people start to think it explains everything. Like how in the 16th/17th centuries some people thought the universe was a big clock. Or how in the 19th centuries people thought the universe was like a big steam engine. Or now we think the universe is a big computer. Not saying this is wrong or that I've watched all of the lectures above or anything, b…

Couldn’t all of them be right, though? In the sense that every technology associated with the functioning of the universe had a systemic, spatiotemporal and evolutive dynamic, which appears to be the sensible facets of the universe’s behavior? In that sense computation is no different, just has more primacy. It gives me some Hofstadter vibes, meaning whatever complex thing we produce within the universe is hopelessly bound to be analogous with it.

Re: Computation as a universal and fundamental concept

#96

Post by RandomLensman »

Maxatar wrote: post #5
sgt101 wrote: post #2

Computation has turned out to be a far more general concept than I think was imagined, up to the point that many computer scientists now seem to equate computation with the functioning of the universe. Recently it's been shown that there are real, physical processes which are undecidable (we cannot know if a latice of atoms has a spectral gap or not, we cannot determine if a specific particle in a fluid flow will rea…

>Recently it's been shown that there are real, physical processes which are undecidable I want to push back a bit on this claim along two dimensions. Imagine a physical Turing machine built out of atoms, gears, levers, and an electron parked on the read/write head and ask whether that electron ever crosses some fixed plane in space, which it does only when the machine enters its halt configuration. That's now a purel…

How to build a Turing machine to tell which one of ten atoms of a radioactive element decays next?

Re: Computation as a universal and fundamental concept

#97

Post by voidhorse »

BirAdam wrote: post #73
Diogenesian wrote: post #65

Earlier quoted context omitted.

Information and computation are not the same thing. I was very specifically talking about Turing machines and other theoretical models of computation. That said, you are still making the same mistake I pointed out, elevating human symbolic information to a higher plateau than it deserves. I think it's because you're being too vague about the connection, when it's fairly mundane. The "fundamental connection" is that p…

I’ve always hated the use of the word “information” in relation to things like spin. Information and order are effects of human perception and preference. They exist as abstractions in the mind and not in reality.

This. I'll never understand people who reify "information" as though it is some object with independent existence from man.

No information without an interpretation. The "amount" of information is completely dependent on the observer.

You'd think people who work constantly with abstraction wouldn't fall prey to reifying abstractions but they actually seem more susceptible to it than anyone else.

Re: Computation as a universal and fundamental concept

#98

Post by voidhorse »

jibal wrote: post #94
jibal wrote: post #86

Earlier quoted context omitted.

I know what metaphysics is (and your description isn't accurate--science is a knowledge-producing method that doesn't depend on metaphysics in order to be meaningful), but that has nothing to do with my statement. And it's called "metaphysics" because Andronicus placed that volume after the "physics" volume when he organized Aristotle's writings.

I asked for proof of claims and I just get "it absolutely does" and a bunch more assertions, and word salad like "the validity of the scientific method is ultimately a metaphysical extension of our intuitions about inductive reasoning and causality" -- there's nothing "metaphysical" about it ... the scientific method is a disciplined application of an effective process of discovery. And '"Our intuitions" is why I sai…

There is no single "scientific method" to speak of. Your epistemic position is ultimately just as faith based as you claim faith in God etc. is, the sciences (plural) just have a set of operations which, as you point out, seem to have practical utility and seem to be better than certain alternatives for building up shared epistemic structure.

The attitude of "we can't do better" is precisely the kind of attitude that would have hampered the creation of various sciences and their methods in the first place, and the production of scientific thought is often not as pure or logically consistent as all the methodological purists or Popperians seem to believe it is. Feyerabend, Quine, Von Foerster, Dataon and Gallison and several others have made this pretty clear and make the argument pretty forcefully in my opinion.

All sciences carry an ontology and value system along with them. Religion is also a rich and highly effective epistemic structure when your underlying ontological assumptions, values, and goals differ from those established and implicit in the scientific (predominantly utilitarian) Western enlightenment value system. Science is not able to found itself on some irrefutable bedrock "truth" correspondence any more than religion is. There is no basis by which we can actually solidify empiricism as somehow more privileged and more capital T true if we admit the possibility of human error.

Re: Computation as a universal and fundamental concept

#99

Post by curiousest »

Robotbeat wrote: post #60
Diogenesian wrote: post #49

There are a lot of long comments basically saying what I am about to say so I will try to keep this brief: Computation is a metaphysically universal and fundamental concept, since metaphysics is (tautologically) the domain of humans and we use symbolic communication. So of course very general theories of symbolic processes (e.g. Turing machines) are pertinent to the symbolic methodology we use to understand scientifi…

This is a misconception. It’s more fundamental than that. There’s a fundamental connection between (Shannon) information theory and thermodynamics. The Landau Limit, whether blackholes can destroy information or not, quantum mechanics, etc. Information is actually tangible . It’s not just an analogy or a coincidence that the word “entropy” is a word used in both physics and computer science (information theory). Ther…

You can say things like, “In the domain of physics, X,” “Assuming the scientific method, X,” or “Assuming the premises of logic, X.”

But “computation is a fundamental aspect of the universe”, in the way it's being understood in this thread (as opposed to the article) does not remain within any of those frameworks. It makes a claim about reality as a whole.

Once you make that kind of universal claim, all the assumptions built into “computation” - about identity, distinct states, lawful transitions, causation, logic, etc. - become part of the claim. You cannot use those assumptions silently and then present the conclusion as framework-independent.

And those frameworks come with consequences. Using the language of computation, they come with "lossiness" wrt modelling "reality".

(see Aristotle Metaphysics -> Kant CoPR -> later Wittgenstein)

Re: Computation as a universal and fundamental concept

#100

Post by voidhorse »

Computation as realized by computers is a formalism invented by Turing, Church, Kleene and others to make precise the intuitive notion of "algorithm".

An algorithm, at its root, is a procedure rooted in human understanding that human beings can follow.

When Turing and others first introduced this formal notion, not all mathematicians were even fully convinced it was an adequate representation of the informal intuitive notion. For example, some argued it was too broad because traditionally knowing that an algorithm eventually terminates was one of the requirements (to some) for something to be a legitimate algorithm. Why? Because the idea is rooted in human practical concerns and human understanding. Depending on what one cares about, one could actually reject the Turing formalization of algorithm on grounds of the class containing non-convergent (partial) functions.

All this is to say that "computation" is very much a human invention and little more than a formal model of human behaviors (we want to manipulate things algebraically). Elevating it to some objective substance of the universe is just doing 17th/18th century philosophical Idealism wrapped in new clothes.

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