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Old 05-20-2019, 11:37 PM
Half Man Half Wit's Avatar
Half Man Half Wit is offline
Join Date: Jun 2007
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Originally Posted by begbert2 View Post
Are you asserting that it's impossible for any computational system to assign symbols to new concepts as it encounters them?
No. And, frankly, your continued misconstrual of my argument is somewhat disconcerting to me. I've given an explicit example of what I'm arguing in post #93: there, I have shown how one and the same physical system can be considered, on equal grounds, to perform distinct computations (binary addition---f---and the function f').

Hence, what computation a physical system performs---whether it performs any computation at all---isn't an objective matter of fact about the physical system. You can't say the device I proposed performs binary addition; you can only say that you can interpret it as such.

But then, a dismissal of the computational theory of mind follows immediately. Computationalism holds that brains give rise to minds via performing the right sort of computation. But if it's the case that brains don't perform any computation at all, unless they are interpreted in the right way, then that whole thing collapses.

So whether or not a computational system assigns symbols to concepts, or what have you, is entirely beside the point. The point is that there's no such thing as a computational system absent an interpretation of a physical system as a computational system.

We're not talking about orrerys and maps, and you know it - we're talking about functionally exact copies. At a functional level the digital copy would operate exactly the same way the original physical person did. So forget all the crappy analogies, please.
The analogy is exact in the one respect that matters: neither an orrery nor a map is intrinsically about what we use it to model, but needs to be interpreted as such. The same is true with computation.

The rest of your post unfortunately doesn't really have any connection to anything I've written so far, so I won't reply to it for now, for fear of introducing yet more confusion in the attempt of explaining myself. Really, I implore you, if any of this is still unclear, go back to my example. If you don't understand something, ask. But don't just go on attacking points I never made.

Originally Posted by RaftPeople View Post
HMHW, I'm curious which definition of computation (or computationalism if it's a different animal) you are assuming?
Well, as I put it earlier:

Originally Posted by Half Man Half Wit View Post
Computation is nothing but using a physical system to implement a computable (partial recursive) function. That is, I have an input x, and want to know the value of some f(x) for a computable f, and use manipulations on a physical system (entering x, pushing 'start', say) to obtain knowledge about f(x).

This is equivalent (assuming a weak form of Church-Turing) to a definition using Turing machines, or lambda calculus, or algorithms. What's more, we can limit us to computation over finite binary strings, since that's all a modern computer does. In this case, it's straightforward to show that the same physical system can be used to implement different computations (see below).
Computationalism then is the idea that the way the brain gives rise to a mind is by implementing the right sort of computation.

Last edited by Half Man Half Wit; 05-20-2019 at 11:38 PM.