Bruno Marchal wrote: > Le 23-oct.-06, à 14:29, 1Z a écrit : > > > > > > > Bruno Marchal wrote: > >> Le 20-oct.-06, à 17:04, 1Z a écrit : > >> > >>> As usual, the truth of a mathematical existence-claim does not > >>> prove Platonism. > >> > >> By Platonism, or better "arithmetical realism" I just mean the belief > >> by many mathematician in the non constructive proof of "OR" > >> statements. > > > > So where is the UD running? If Platonia doesn't exist, > > how can I be in it? > > > > You miss the point. For asserting that the UD exists, I don't even > need to use the non-constructive OR. The UD exists for an intuitionist > as well. > ("exists" in the same sense that it exists a number which is not the > sum of three squares (x = 7 for example).

That doesn't answer the question. I am not saying mathematical statements asserting the mathemtical existence of a UD, or the number 7, are false. I am asking what mathematical existence means. Where do mathematical objects exist? In the physical world? In Platonia? In mathematicians minds? Nowhere? > I think that in many of your last posts you are begging the point. You > seem to assume the existence of a physical universe, then you define > "existence" by existing in the physical universe. No, I am just asking. I have even come up with formulations like "real in the sense that I am real" which avoid begging any questions about what kind of reality I have. >I don't assume a > physical universe. I define existence by the arithmetical truth of (mathematical) >existential sentences. But for anti-Platonists the truth of mathematical statements has no existential consequences. > Then I explain in all (technical thus) details > why immaterial machines/numbers come to feel, perceive, know, believe > in sharable quanta and unsharable qualia. Assuming immaterial machines exist. > You say somewhere that we see matter. I think that this is the main > difference between you and me, and I would say between Aristotle and > Plato: Aristotle (like St-Thomas) argues indeed in his metaphysics that > what we see and measure is what really exist (so that we can sleep in > peace). Plato and actually most (rational) mystics (from Pythagorus to > St-Augustin) try to explain that what we see could as well be only the > shadows of the shadows of the shadows of the shadows ... of what > perhaps is (so that we have to keep our vigilance and our skepticism or > our doubting abilities in front of *all* theories (especially including > those who could have been built in by long evolutionary processes). Matter can only be a shadow of something that exists. > All what I say is that (standard) computationalism is epistemologically > incompatible with materialism. It *is* a necessary-redundancy argument: > even if matter exists, standard comp makes it impossible to use for > justifying any stable belief. But that isn't true. Matter can only be made redundant by some form of immaterial existence. However immaterial existence, is *not* implied by *standard* computationalism. Claims that computationalism necessitates the truth of mathematical existence claims does not prove immaterial existence, unless you can refute the anti-Platonists argument that mathematical "existence" is non-existence ontologically. > That is the conclusion of the UDA. The UDA has to assume the existence of a UD, and that is not given by standard computationalism. It is given by Platonism. > The > AUDA makes it constructive and can generate the physical laws > completely (making comp or acomp 100% scientific (popper-testable). > It remain possible that the translation of UDA in arithmetic is to > rough, and that is why I say "comp or acomp". But until now, empirical > physics seems to confirm all the "weird" prediction of (a)comp. > > > 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 [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/everything-list -~----------~----~----~----~------~----~------~--~---