Why Minds Are Not Like Computers (2009)

http://www.thenewatlantis.com/publications/why-minds-are-not-like-computers

by prostoalex • 11 years ago

23 45 11 years ago

This is why people not trained in CS shouldn't speculate on it, when they do you get garbage like this.

The brain performs computation, it is by definition a computer. Before modern computers there was a human job, called, computer. One who performs computations. The analogy of the brain to a computer is perfect, because the brain is a computer.

cheradenine012• 11 years ago

Nope. Go read Penrose.

There are problems that the brain can solve, but you can (provably) show that an algorithm cannot. For example - tesselation on an infinite plane.

innguest2• 11 years ago

I googled for tessellation infinite plane algorithm but could not find any pertinent information.

There are problems that the brain can solve that one can prove an algorithm cannot. That to me is a bold claim. Could you point to material I could read on this?

cheradenine012• 11 years ago

The Emperor's New Mind (and the followup whose name I forget).

There's a rather scratchy recorded documentary here https://www.youtube.com/watch?v=eVq39QbFQXE

See also: https://en.wikipedia.org/wiki/Wang_tile n 1966, Wang's student Robert Berger solved the domino problem in the negative. He proved that no algorithm for the problem can exist, by showing how to translate any Turing machine into a set of Wang tiles that tiles the plane if and only if the Turing machine does not halt. The undecidability of the halting problem (the problem of testing whether a Turing machine eventually halts) then implies the undecidability of Wang's tiling problem.

theaiguy5• 11 years ago

Nope. Can I suggest you read Penrose again with a little more critical thought.

There are problems it is possible to prove are not computable. But can you prove that human beings can solve them?

Tessellation of the infinite plane? Please demonstrate a person that can solve this (i.e. not that they have a > 99.9% chance of being able to do it, or that you can show they can start out pretty successfully and you assume they'll always stay ahead of the game).

Bear in mind when working out if a computer can solve a given problem (i.e. is it mathematically computable), we're not trying to work out if it can ever solve it, or even if it can solve it in infinitely many cases, or even in an arbitrarily high proportion of cases. We're working out if it can be proven that it is (not) guaranteed to find a correct solution in all cases. There's just no way to make those judgements of a human being.

So instead, mathematical analysis of computation is compared against intuition arguments from the evidence that human beings have good, reliable strategies for solving some of them. Unsurprisingly, the brain comes off pretty well in that comparison!

Penrose was big on handwaving and appeal to quantum magic, but not very good on the specific arguments to back up his claim.

I found this article to be a huge bag of misconceptions about AI, computation, and the actual claims of AI professionals. As an argument against hyperbolic media mischaracterisation, it might be reasonable. But like Penrose, it manages a long and condescending argument from intuition that fails to take seriously the actual claims being made.

[Edit: for clarity and spelling]

Sharlin• 11 years ago

Such overconfidence. There is no generally accepted evidence that anything physical, whether brain or something else, can compute something a TM cannot compute. Penrose's claims are conjectures at best and pseudoscience at worst.

justinpaulson6• 11 years ago

Except the author does in fact have a BS in CS. IMO, the brain does far more than performing computation. Sure humans were once "computers," but our ability to perform computation is not a valid argument to that computation, or the inner workings of our mind, being the same as digital computers performing computation. You failed to look up the author's credentials and I feel like you may have also failed to read the entire piece.

theaiguy5• 11 years ago

the brain does far more than performing computation

In your opinion? Can you be more specific, and give examples of things the brain does that are not computable?

This is trivially true in some senses, neurones have analogue responses, that the biology does a good (but not perfect) job of thresholding. But then, the same thing can be said of transistors. It's just we're able to engineer their analogue responses out much more successfully than evolution has. It is also true that the brain is connected to a much broader system which is undoubtedly analogue (i.e. the body), but then again, it isn't clear that isn't true of any non-abstracted computer.

Comparing theoretical and idealised computing to embodied brains might feel insightful, but it doesn't actually resolve any of the real issues in the philosophy of AI.

Also, a BS in CS isn't a good minimum qualification for competency in the philosophy of AI. I wouldn't read much into that.

UK-AL• 11 years ago

Computers can simulate electrical and chemical interactions, given enough computational power could you not simulate it at that level?

yew2• 11 years ago

. . . our ability to perform computation is not a valid argument to that computation, or the inner workings of our mind, being the same as digital computers performing computation.

No one [1] thinks that the human brain is likely to be a digital computer performing arithmetic on fixed-width binary integers and IEEE floating-point numbers. The argument for AI is simply that the mind appears to be a material object and the laws of physics appear to be Turing-equivalent. If that holds, the mind is provably equivalent to a Turing machine (or, less likely, some less powerful class of automaton). Arguing about whether in fact that does hold, as Penrose does, can be justified (though I personally think Penrose lost the plot years ago). Arguing about whether your preferred model for categorizing abstract ideas renders the argument inconceivable, with no reference to experimental results or formalisms, can not.

[1] Feel free to add your preferred qualifiers here. The existence of people who believe tobacco companies are run by lizard-people has no bearing on whether cigarettes cause lung cancer.

pjungwir3• 11 years ago

It seems like you are the one speculating . . . about the author's credentials.

Also, the fact that thinking includes computation does not imply that computation includes thinking. There is a strong case that the brain is a computer, but really no one knows. Even if the brain is 100% material, there are people who argue it cannot be simulated on a computer. In part what we're talking about is the Church-Turing Thesis, which is still just a conjecture.

wwweston4• 11 years ago

It's not clear how much the brain is like most of the computers even CS specialists or engineers have encountered. Actually, that's putting it mildly. AFAICT it's pretty accurate to say that the brain is about as far from a Von Neumann computer as it is from older favorite analogies like clockwork.

Also, while it's clear the brain can do computation, it's not clear that everything it does is computation.

sudo_free_cake3• 11 years ago

If you take models of computation you will learn anything that can do computation is a computer. A bag of rocks is a computer, you can add and remove rocks to perform computation.

coldtea2• 11 years ago

The brain performs computation, it is by definition a computer.

Citation needed.

Actually that's the standard motto of any era -- the brain was like god (soul), then like gears in the early mechanical era, and so on to the computer analogy.

palosanto• 11 years ago

"If we achieve artificial intelligence without really understanding anything about intelligence itself then we will have no idea how to control it."

Exactly. It's fascinating/scary to me how people still talk about A.I. or machine consciousness when we basically have no idea how consciousness works in general.

sullyj3• 11 years ago

People who say things like that don't understand how to reason using limiting cases. We have artificial intelligence right now. Maybe not artificial general intelligence, but plenty of stuff traditionally thought of as being solely the domain of minds, is now performed by software. I'd say we understand it pretty well, and we certainly have the ability to control it.

scarmig• 11 years ago

The one iron-clad rule of artificial intelligence: any successful attempt at implementing it makes it not artificial intelligence, just something that computers are able to do.

(Though I guess there is the second rule of over-optimistic timelines, to be fair.)

taniraja• 11 years ago

Is cognitive dissonance computable?

le0n• 11 years ago

A great article on similar issues is "Turing Test: 50 Years Later":

http://crl.ucsd.edu/~saygin/papers/MMTT.pdf

It touches on the "physics is computable therefore the mind is computable", and similar such arguments, in a fascinating and IMO balanced way.

Why Minds Are Not Like Computers (2009)

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