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Why Minds Are Not Like Computers (2009)

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Re: Why Minds Are Not Like Computers (2009)

#41

Post by Sharlin »

ars wrote: post #29
netcan wrote: post #15

Earlier quoted context omitted.

To me the most convincing discussions of artificial or engineered minds start with: "human minds exist" Therefore, whatever it is that minds do is possible.

Both you and the parent have assumed without evidence that the mind operates by local physical laws. There is certainly no evidence to the contrary, but an absence of evidence is not evidence. Religions might be right and the mind is actually the soul. Or we could all be characters in a virtual world "played" by beings operating us. This world could be an elaborate RPG. Or something else we haven't figured out yet. S…

There are no proofs outside pure mathematics; science works based on justifiable beliefs. Absence of evidence is evidence of absence; we don't need to prove unicorns don't exist to ignore their potential existence in our model of the universe. The null hypothesis is that brains are not magic.

Re: Why Minds Are Not Like Computers (2009)

#42

Post by truantbuick »

eli_gottlieb wrote: post #21
tikhonj wrote: post #8

It feels like this article sets up something of a straw man. The analogy that a mind is like a computer is just that, an analogy . It's used to present the high-level structure of the brain in a accessible, understandable way, not as a logical argument. This analogy is not the justification for why people believe that "the mind can be replicated on a computer". And yet the article tries to disprove the latter, deep a…

It's just the Church-Turing Thesis all over again, with a dash of metaphysical nondeterminism. So far, everything in reality seems to be "made of" either determinism or randomness. There might be a third option (and options beyond that), but we haven't seen one or thought of one yet. So far, computation can model determinism perfectly well (after all, computation is just very orderly, bottled-up determinism harnessed…

I'm no expert myself, but I thought the Turing-Church thesis implied the exact opposite. Turing machines and lambda calculus are widely assumed -- though not proved -- to be the limits of what can be computed. And yet, in a Gödelian fashion, for a given computer (equiv. set of finite axioms), you can always formulate deterministically true statements that cannot be computed.

Note that the formulation of these are counter-examples and thus assert a fundamental limit of computation, but it says nothing that there might be many other things that are non-computable that do not fit the form of these counter-examples.

Re: Why Minds Are Not Like Computers (2009)

#43

Post by Sharlin »

bencollier49 wrote: post #10
malka wrote: post #7

Earlier quoted context omitted.

Given that you can emulate a turing machine in your mind, I'd assume that it is more than a Turing machine.

But no infinite tape. I can't remember if that's essential to the definition of a Turing machine?

Obviously no physical machine can have an actual unbounded tape (note that unbounded is not the same as infinite!) The interesting question is whether the brain is Turing-equivalent if given a notebook with an unlimited number of pages to keep track of the program state.

Re: Why Minds Are Not Like Computers (2009)

#44

Post by andrewmu »

treekiller wrote: post #40
tikhonj wrote: post #8

It feels like this article sets up something of a straw man. The analogy that a mind is like a computer is just that, an analogy . It's used to present the high-level structure of the brain in a accessible, understandable way, not as a logical argument. This analogy is not the justification for why people believe that "the mind can be replicated on a computer". And yet the article tries to disprove the latter, deep a…

Hes not saying that the mind can't be replicated. Hes just suggesting that the approach is wrong, that many of the claims routinely made by AI are not supported by empirical observation. For example, that the neuron is a unit of the brain. There are so many falsehoods just accepted, left-brain, right-brain personalities for example. Hes not some dualist, resorting to spiritual explanations.

Yes, criticising the current popular models is valid, but doesn't suggesting that strong AI is impossible in theory allow a dualist or mystical view?

Re: Why Minds Are Not Like Computers (2009)

#45

Post by Sharlin »

malka wrote: post #7
danieltillett wrote: post #2

I would have thought it was obvious that minds are not like computers, the really interesting question is are minds Turing machines?

Given that you can emulate a turing machine in your mind, I'd assume that it is more than a Turing machine.

It is not proven that a human mind can emulate all Turing machines (given an arbitrary amount of external storage). All physical computers are "just" finite state machines (because they don't have unbounded storage); you can emulate a subset of Turing machines using an FSM just fine even though a TM is strictly more powerful than an FSM.

Re: Why Minds Are Not Like Computers (2009)

#46

Post by tim333 »

My the article rattles on a bit in the typical way of philosophers where it's hard to analyse what's up with their arguments because they lump about a hundred of them together. But I think there is a basic straw man argument in implying AI researchers think of the mind as software. I think a more reasonable model in AI is for software to simulate the computational action of the neurones and for the mind to be analogous to the data that the software or neurones operate on. If you believe the brain is a machine following the laws of physics then this should be possible. The proof is in the pudding. Researchers have already been able to produce functional simulations of the retina and parts of the hearing system and get similar signals out which can then be fed back in to the brain successfully as seen in the contraption on Rush Limbaugh's head.

Whether that extends to the rest of the brain we will see before long. The Blue Brain / Human Brain Project has a €1bn grant to get cracking on it. Time will tell.

http://www.theguardian.com/science/2013/oct/15/human-brain-p...

Re: Why Minds Are Not Like Computers (2009)

#47

Post by netcan »

ars wrote: post #29
netcan wrote: post #15

Earlier quoted context omitted.

To me the most convincing discussions of artificial or engineered minds start with: "human minds exist" Therefore, whatever it is that minds do is possible.

Both you and the parent have assumed without evidence that the mind operates by local physical laws. There is certainly no evidence to the contrary, but an absence of evidence is not evidence. Religions might be right and the mind is actually the soul. Or we could all be characters in a virtual world "played" by beings operating us. This world could be an elaborate RPG. Or something else we haven't figured out yet. S…

I disagree, though not with absolute confidence. Incidentally, i love how fast AI discussion degrade into existentialism.

Even if minds need unknown 'laws' emerging from dualistic nature of existence, they still exist.

Whether we are human beings in a world that is as it seems, characters in an RPG game, brains in a vat, souls tortured by a demon, artificial minds somewhere in a cascade of simulations or dreaming Hindu gods, we are (or rather I am) still minds under the des cartes definition of a mind and that mind exists.

As for not confusing proof with belief… Occams razor has value. Even if the religious view of souls or such is possible, it is not based on any knowledge or information. It's made up. It has a kind of a longshot chance of being correct in the same way early philosophical claims that matter is made up of wind, fire, earth and water were had a longshot chance of being correct.

In any case, minds seem to have a lot to do with brains and brains are nice squishy physical things that can be prodded and examined and haven't yet been seen to do stuff that is impossible in a material universe.

Re: Why Minds Are Not Like Computers (2009)

#48

Post by lifebeyondfife »

I'd take the argument to the physical level. Do we know how the brain works? To some degree, yes. Neural networks: nodes, weights and activation functions.

If one day we can map exactly an animal brain's architecture, how new ideas are learned etc. (is it backwards propagation or something else?) then we can replicate that behaviour using logic gates and floating point numbers.

Mapping a brain to a digital neural network architecture is such a prohibitively expensive problem I wouldn't know where to begin. Perhaps a biologist would have a better idea than a computer scientist. But it's enough to say that intelligence can theoretically exist on electronic circuits.

Re: Why Minds Are Not Like Computers (2009)

#49

Post by eli_gottlieb »

truantbuick wrote: post #42
eli_gottlieb wrote: post #21

Earlier quoted context omitted.

It's just the Church-Turing Thesis all over again, with a dash of metaphysical nondeterminism. So far, everything in reality seems to be "made of" either determinism or randomness. There might be a third option (and options beyond that), but we haven't seen one or thought of one yet. So far, computation can model determinism perfectly well (after all, computation is just very orderly, bottled-up determinism harnessed…

I'm no expert myself, but I thought the Turing-Church thesis implied the exact opposite. Turing machines and lambda calculus are widely assumed -- though not proved -- to be the limits of what can be computed. And yet, in a Gödelian fashion, for a given computer (equiv. set of finite axioms), you can always formulate deterministically true statements that cannot be computed. Note that the formulation of these are co…

Hence why I'd said Turing-recognizable rather than Turing-decidable.

Re: Why Minds Are Not Like Computers (2009)

#50

Post by andyjohnson0 »

eli_gottlieb wrote: post #21
tikhonj wrote: post #8

It feels like this article sets up something of a straw man. The analogy that a mind is like a computer is just that, an analogy . It's used to present the high-level structure of the brain in a accessible, understandable way, not as a logical argument. This analogy is not the justification for why people believe that "the mind can be replicated on a computer". And yet the article tries to disprove the latter, deep a…

It's just the Church-Turing Thesis all over again, with a dash of metaphysical nondeterminism. So far, everything in reality seems to be "made of" either determinism or randomness. There might be a third option (and options beyond that), but we haven't seen one or thought of one yet. So far, computation can model determinism perfectly well (after all, computation is just very orderly, bottled-up determinism harnessed…

Interesting argument. Is it fair to summarise it as: (a) Mathematics models the deterministic and random aspects of reality; (b) Mathematics reduces to computation; (c) Church-Turing says that all computation is equivalent; (d) Therefore a Turing machine[2] can fully model reality.

"When you get deep enough, mathematics is in fact reducible to computation (paging Robert Harper)."

Could you elaborate on that, as it seems to be a big jump? I'm not familiar with Harper's work (I'm assuming you mean this [1] Robert Harper). I'm also not a mathematician...

[1] http://en.wikipedia.org/wiki/Robert_Harper_(computer_scienti...

[2] Or, presumably, Lambda calculus or Godelian recursion.

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