Thanks Bruno for being so patient with me and taking the time to carefully answer my queries.

## Advertising

Nick On Oct 28, 3:42 pm, Bruno Marchal <marc...@ulb.ac.be> wrote: > On 28 Oct 2011, at 01:56, Nick Prince wrote: > > > > > [BM] > > The QTI, or the more general comp immortality, or arithmetical > > immortality is a complex subject, if only because it depends on > > what > > you mean by "you". > > > [NP] > > > Can you be more specific on this? > > Well, we have discuss this a lot on this list. Once you accept the > hypothesis that we are digitally emulable, it can be shown that we > have to distinguish the first person subjective life from the > plausible third person description of the body related to that person, > and that the problem of relating those first person description and > the third person description are not yet solved. But for the > immortality question, we are obliged to consider thought experience > involving amnesia, and those experiences illustrates that the notion > of personal identity is quite relative, and, with mechanism, they > makes no absolute sense at all. They might depend on what *you* want > to consider as being *you*. You might consider to be immortal just by > succeeding to identify you with your core universal identity (the > universal machine that you are), and in that case you can consider > that you could survive a strong amnesia. Some drug can help some > people to "realize" such identification. But we are programmed by > nature to resist such identification, and to identify ourselves with > our "little ego" which contains our mundane personal histories, and > this can make you doubt that you could survive amnesia. Immortality > might be a question of personal choice. Assuming mechanism, the > question of afterlife can today be shown as being very difficult. > Indeed, mechanism breaks the usual mind-brain identity thesis, and > consciousness is related to the infinitely many arithmetical relations > defining consistent extensions of (relative) computational states. The > math leads to a sequence of open problems. > > > > > > > > > [BM] > > Do you know Kripke semantic? A Kripke frame is just a set (of > > elements > > called worlds) with an accessibility relation among the worlds. In > > modal logic they can be used to characterize modal logical systems. > > The basic idea is that []p is true in world alpha, if p is true in > > all > > the worlds accessible from alpha. Dually, <>p is true in alpha is p > > is > > true in at least one world accessible from alpha. For example the > > law > > []p -> p will be satisfied in all reflexive frames---independently > > of > > the truth value of p. (a frame is reflexive if all the worlds in > > the > > frame access to themselves; for all alpha alpha R alpha, with R the > > accessibility relation). > > > [NP] > > Sorry but I have no experience in this area but I can see that if yoU > > adopt non classical logic then it opens up all sorts of > > possibilities. > > With the mechanist theory/assumption, I find it better to keep > classical logic, and to derive the non classical logic from the > intensional variants of the logic of self-reference. We have the > mathematical tools to study in a clean transparent way all those > intensional nuances (which can be proved to exist necessarily as a > consequence of the incompleteness phenomena). > > It should be obvious that with the mechanist hypothesis, computer > science and mathematical logic can put much light on those questions. > But those math are not very well knows (beyond professional logicians). > > > Testing the consequences in reality is the tricky > > part. tHE Quantum mechanical formalism has been successful in so > > many respects so it gives us some confidence of being on the right > > track. > > But then you do have the QM interpretation problem. The Everett theory > is based on comp (alias mechanism), and I have shown that comp > generalizes QM. A priori there are more computations than quantum > computations, but a posteriori the quanyum computations can win a > "measure battle" in the limit. > > > > > > > > > [BM] > > > Then, as other have already mentioned, what will remain unclear > > (and > > hard to compute) is the probability that you survive through some > > memory backtracking. The cat might survive in the worlds where he > > has > > been lucky enough to not participate to that experience, and, for > > all > > we know, such consistent continuation might have bigger weight than > > surviving through some quantum tunnel effect saving the brain's cat > > from the poison. The computation here are just not tractable, if we > > assume quantum mechanics, and still less, assuming only the comp > > hypothesis. The only certainty, assuming comp or QM, is that "you" > > cannot die. But obviously you can become amnesic of some part, if > > not > > all, your existence, or you existences. Like Otto Rossler summed up > > well : consciousness is a prison. With comp, and I think with QM, > > there is no escapes from being conscious, in a way or another. I > > don't > > like that, but then it is a consequence of those theories. > > > [NP] > > Consciousness could be a prison yes. but MWI may be false of course, > > in which case maybe not. If comp says yes it is - as you suggest, > > then that's another matter. The question then is: is comp more > > fundamental than QM and if this be the case, > > Comp is more fundamental that QM. Yes. I argue in that direction since > a long time. It is not easy because it literally force us to backtrack > toward Plato, and to abandon Aristotle metaphysics (but not > necessarily his logic, biology, and even physics up to some obvious > correction). But the basic idea is that with comp the physical reality > is not the fundamental reality. The physical reality becomes the > "border" of the universal mind (of the universal machine(s)). To be > short. > > > should there not be some > > way we can utilise its predictive capabilities to distinguish (prove?) > > which interpretation of QM is the right one? > > Comp extends the MWI of physics into a MWI of arithmetic. > Theoretically you can derive the whole of physics from the numbers' > addition and multiplication laws by using the machine self-reference > logics. Up to now, we find a quantum logic rather similar to the one > by von Neumann and Birkhoff, but it is an open problem if it is > (ortho)modular or if we need von Neumann algebra or sub-Hilbert > spaces, finitely or infinitely dimensional, etc. > > The practical weakness of such an approach to physics, is that it is > very complex mathematics. > The conceptual advantage is that we can distinguish the logic and math > of the quanta and the qualia. The qualia are characterized by > accessible but unprovable truth (for the machine) obeying to the > probabilistic variant of the provability predicate. The main variant > here is the "no-cul-de-sac-definition": that is the substitution of Bp > (beweisbar 'p') by Bp & Dt (beweisbar 'p' and consistent 'truth'). The > adjunction of Dt (diamond t, consistent 't') makes the machine > abstracting from the cul-de-sac worlds. > > Of course, for the ideally correct machine, Bp implies Bp & Dt, but > the machine cannot prove that (it would prove Dt which is impossible > by the correct machine incompleteness). > > I am sorry if this looks a bit technical, but in that very complex > subject, being technical is the only way to be shown wrong and to > progress. > > Bruno > > http://iridia.ulb.ac.be/~marchal/- Hide quoted text - > > - Show quoted text -- Hide quoted text - > > - Show quoted text - -- 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.