Re: Edge.org: 2014 : WHAT SCIENTIFIC IDEA IS READY FOR RETIREMENT? The Computational Metaphor

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On 18 Jan 2014, at 01:48, meekerdb wrote:```
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```On 1/17/2014 2:04 PM, LizR wrote:
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```On 17 January 2014 18:03, meekerdb <meeke...@verizon.net> wrote:
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Briefly, computationalism is the idea that you could replace the brain
```with a Turing machine and you would preserve the mind. This would not
be possible if there is non-computable physics in the brain,

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Just to clarify, as I understand Bruno's theory, there is non- computable physics in the brain. In fact physics is non-computable in general, BUT the mind is computable, i.e. the level of substitution that preserves the person is above the fundamental physics level. I actually think this last is dubious.
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I also find it unlikely that the subst level is above the quantum level. Or at least I think that if it's at the quantum level then we can guarantee that the duplication arguments would work (assuming we could duplicate objects at that level, which we can't due to a fundamental principle...!)
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Actually Brent, your comment above reads like a refutation of comp, which I suspect isn't the intention.
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Or is it? I read it as

1 Comp says fundamental physics is non-computable.
2 Comp says the mind is the result of a computation.
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3 Hence if the subst level is at the level of fundamental physics, 2 can't be correct 4 I think it IS at the quantum level, so 2 is wrong, so comp is wrong - QED :)
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I don't think 2 is right. I think comp says that a mind is the result of an infinite set of computations, which are not computable. But Bruno can correct me if I'm wrong.
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It is subtle.

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By comp, "one" computation can brought your mind, in principle. But you need an infinity of computation to have a stable mind relatively to "one" or "an infinity" of computations to not only have a mind, but a stable physics.
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So "one" computation is enough, if it is done relatively to an environment which multiplies it with the right (physical) measure. Like the quantum seem to do. This assure also some notion of first person plural consistency. We can share the (infinity) of relative computations.
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And similarly a physical object, like a neuron or an artificial neuron, is also not computable. But then it may become a question of what does it mean to 'preserve a person' when a person is just an abstraction, a self-modeling piece of the world. How accurately does the substitution have to be to 'preserve'? If I had a silicon based neuron replacing one of my biologically based ones, it might serve fine in transmitting neural pulses. But it might not respond to some hormones. It wouldn't grow. I might respond very differently to a stray cosmic ray particle. But I might still seem to be "me".
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That will plausibly be the case with the first artificial brain. You will survive, but loss some things. But it just means that the level of subst was not adequate enough.
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However, surely comp says the mind is the result of computations in Platonia, rather than in the brain? In fact it says that the brain doesn't exist (along with everything else, apart from Platonia).
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But apparently the brain has a lot to do with those computations in Platonia, c.f. anesthetic. Notice that I'm not a disciple of Platonia.
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You believe that "17 is prime" depends on the physical existence of Brent? OK, but can you explain the dependency? And to answer this properly, you have to define "physical existence of Brent" without using arithmetic.
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Bruno

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Brent

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I feel as though my own brain is about to boggle, or would if it existed. Maybe I should write everything "under erasure" to be on the safe side!
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