On 14 Aug 2009, at 14:34, 1Z wrote:

> > > > On 14 Aug, 09:48, Bruno Marchal <marc...@ulb.ac.be> wrote: > >> You are dismissing the first person indeterminacy. A stuffy TM can >> run >> a computation. But if a consciousness is attached to that >> computation, >> it is automatically attached to an infinity of immaterial and >> relative >> computations as well, > > There's your Platonism. Not mine. The one which follows from the comp assumption, if UDA is valid. > If nothing immaterial exists (NB "nothing", > I don't make exceptions for just a few pixies or juse a few numbers) > there is nothiign for a cosnc. to attach itself to except a propbably > small, probabuily singular set of stuiffy brains and computers. I can understand how easy for a materialist it is, to conceive at first sight, that numbers and mathematical objects are convenient fiction realized as space-time material configuration, perhaps of brains. But those space-time configuration are themselves described by mathematical functions far more complex that the numbers described or explain. This leads to major difficulties, even before approaching the consciousness problem. This shows that a purely physicalist explanation of numbers could lead to difficulties. But the same for a description of any piece of material things, by just that token. So, I am not sure that physicist can be said to have solved the "matter" problem either, and some physicists are already open, independently of comp, to the idea that physical objects are relative mathematical (immaterial) objects. Which of course are "no material". Wheeler, Tegmark, for example. But then with comp, you are yourself an immaterial object, of the kind person, like the lobian machine. You own a body, or you borrow it to your neighborhood, and "you" as an immaterial pattern can become stable only by being multiplied in infinities of coherent similar histories, which eventually the physicists begin to talk about (multiverse). I tend to believe in many immaterial things. Some are absolutely real (I think) like the natural numbers. Some may be seen as absolutely real, or just as useful fiction: it changes nothing. This is the case for the negative number, the rational, a large part of the algebraic and topological, and analytical. Some are both absolutely real, and physically real, they live in "platonia", and then can come back on earth: they have a relatively concrete existence. For example, the games of chess, the computers, the animals, and the persons. But the concreteness is relative, the 'I' coupled with the chessboard is an abstract couple following normality conditions (that QM provides, but comp not yet). Some could have an even more trivial sense of absolute existence, and a case could be made they don't exist, even in Platonia, like the unicorns, perhaps, and the squared circles (hopefully). Each branch of math has its own notion of existence, and with comp, we have a lot choice, for the ontic part, but usually I take arithmetical existence, if only because this is taught in school, and its enough to justified the existence of the universal numbers, and either they dreams (if "yes doctor") or at least their discourse on their dreams (if you say no the doctor and decide to qualify those machines are "inexistent zombies"). There is a sense to say those universal machines do not exist, but it happens that they don't have the cognitive abilities to know that, and for them, in-existence does not make sense. And for a mathematicans, they exists in a very strong sense, which is that, by accepting Church Thesis, they can prove the existence of universal digital (mathematical) machine from 0, succession, addition and multiplication. Both amoebas colony (human cells), and engineers are implementing some of them everyday in our neighborhood, as we can guess. 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 -~----------~----~----~----~------~----~------~--~---