On 01 Nov 2012, at 14:25, Stephen P. King wrote:

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But I agree with comp up to the strong version of step 8!

`But then you have to find the flaw in step 8. as step 8 is done in`

`comp, without adding any assumptions, of course.`

I accept comp with a weak version of step 8 or, I thinkequivalently, a weak version of computational universality: Acomputation is universal if it is not dependent on any oneparticular physical system.

`This is called functional, not universal. It has nothing to do with`

`Turing universality.`

This implies, to me, that there is at least one physical system thatsuch a universal computation can be said to actually run on!

I don't see this.

This goes against the Parmenidean/Platonistic idea of computation asstatic objects in eternity that are completely independent ofphysical stuff!

`Sorry but, by definition, computations are static objects in`

`arithmetic (or in fortanic, Lispic, combinatoric, lambdaic, etc....`

`There are a lot of equivalent ontological choices here.).`

`The physicist have not (yet) found a definition of computation which`

`does not use that mathematical definition. This exists, though, has`

`*many* physical systems are in principle Turing universal. But Turing`

`universal is a mathematical, even arithmetical, (even in the strong`

`logician sense).`

Bruno http://iridia.ulb.ac.be/~marchal/ -- You received this message because you are subscribed to the Google Groups "Everything List" group. To post to this group, send email to everything-list@googlegroups.com. To unsubscribe from this group, send email to everything-list+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/everything-list?hl=en.