On 27 July 2014 19:38, Jesse Mazer <laserma...@gmail.com> wrote: Again I am asking about the logic that explains *why* we should abandon the > notion of a "primitive universal computation" given that we agree with > steps 1-6. I thought when you said the UD would dominate, you were trying > to give an argument for why any notion of a "primitive universal > computation" would somehow become irrelevant to determining measure as long > as we assume it contains an eternally-running UD (which if true would > certainly be a good argument for abandoning the primitive universal > computation as an irrelevant hypothesis, like the argument for abandoning > an absolute reference frame in relativity because even if it existed it > would have no measurable consequences). Maybe I misunderstood you, though.
I'm sure that Bruno can give you a much better and more comprehensive answer than I can on this. However I would reiterate that it is Step 7 and Step 8 which (ISTM) are essential to understanding the dominant role of the UD. Steps 1-6 establish the indeterminacy of localisation after copying and the insensitivity of such localisation to delays in (re-)constitution. These steps are all based on the initial assumption (Step 0) that consciousness is correlated with some classically (and finitely) describable level of brain function that can consequently be copied (at least in principle). But up to (and including) Step 7 it is assumed that all such computation is nevertheless always instantiated by some kind of primitively-physical computer. There's been lot of quibbling about what primitive is supposed to mean here, but AFAICS it just means anything we agree as basic (i.e. underlying everything else) and irreducible. So primitively-physical means that certain (i.e. physical) computations, and these alone, are assumed to comprise the primitive base for everything else. The original point of this thread, as I've said, was to reiterate the implications of Steps 7 and 8 in terms of the "reversal" of physics and computation. I won't recapitulate the arguments here, since they're already given earlier in the thread. In summary, the conclusion is that, to salvage comp or CTM, we must abandon the notion of primitive physics (at least as being relevant in explanation) in favour of primitive computation. But "primitive computation" mustn't in the first instance be understood as *some computation in particular* taking this "basic and irreducible" explanatory role. We are looking rather for something that will stand for a definition of *computation itself*. To establish this notion we need to posit an ontology sufficient to emulate "computation itself". In the UDA, arithmetical relations are accepted as sufficing for this purpose (consult the expert for details) and, in terms of such relations, a sigma_1 complete theory is accepted as defining the necessary scope of computation. The establishment of such a basis for "computation itself", free of any purportedly more-primitive restriction on its scope, is what lets, so to speak, the central notion of the UD "off the leash". In terms of such a theory, an infinitely fractal structure, consequent on the recursive dovetailing implicit in any such theory, will come to dominate statistically the residual measure of any computation in particular. This seems (admittedly with some hand-waving on my part) to be rather obvious in general, if not specific, terms. David -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
