On 06 Feb 2011, at 22:20, 1Z wrote:

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On Feb 5, 7:43 pm, Bruno Marchal <marc...@ulb.ac.be> wrote:Computationalism needs Church thesis which needs AR (Arithmetical Realism).Nope, just AT (arithmetic truth).Actually, comp needs only, for the ontology, the quite tiny complete Sigma_1 truth.As I have stated many times, it doesn;t matter in the least how many or few immaterial objects you attribute existence to. It's like saying pixies exist, but only a few

What? It is always better to make a theory precise.

Please don't put metaphysics where there is only religionBelieving in what is not proven is religion. I can argue for anti realism.

`I argue in favor of nothing. That's philosophy. You force me to be`

`explicit on this; I do science. I am a logician, and I show that`

`rational agent believing in comp believe that ... etc. I don't know`

`about the truth.`

(saying yes to the admittedly betting doctor).Saying yes to the doctor will not guarantee your immaterial existence if there is no immaterial existence.

`But there is immaterial existence. I recall you that I say in the`

`ontological context that something exist if Ex (bla-bla-bla x) is true`

`in the standard model of arithmetic. I use the standard meaning of`

`existence of numbers, etc.`

AR/Platonism is a separate assumption to yes Dr.

`I have drop out AR. You need AR (in which everyone believes except the`

`ultrafinitists and the bad faith philosophers) to understand the term`

`"digital" used by the doctor.`

<And with comp,it is math, indeed, even (full, above Sigma_1 arithmetic. Arithmetical realism is what you need to apply the excluded middle in computer science and in arithmetic.The excluded middle is a much of a formal rule as anthing else. Formalists can apply it, so it is compatible with anti realism.

`The theory admits a formal study. You don't act like a formalist at`

`all. The term "Formalism" makes not an atom of sense without`

`arithmetical realism. In philosophy arithmetical realism is the weaker`

`of all possible realism, except again for the ultrafinitists.`

`If you are formalist and anti realist on the numbers you are in`

`contradiction, or, once and for all, just replace numbers by the`

`following formal expression 0, s(0), s(s(0)), etc. + the axioms I just`

`sent to Andrew, etc.`

`AUDA provides more than a formalism, it provides an arithmetisation,`

`which is a *weakening* of formalism, made possible by AR. GĂ¶del`

`already exploited this.`

To understand the fundamental consequences of Church thesis you need to accept that some program computes function despite we have no means to know if it is total or partial, or that a program will stop or not.And I can accept that by positing LEM as a formal rule. I don;t have to posit an immaterial Plato's heaven

`I make clear that the immaterial Plato Heaven for the machine is just`

`the truth of arithmletical proposition. It is an non arithmetical`

`notion, union of the entire Kleene-Mostowki arithmetical hierarchy,`

`and well know non controversal mathematical object in the field of`

`logic.`

`I use the "immaterial Plato heaven" terminology, either as poetical`

`shortcut, or as a point in the arithmetical representation of some`

`term in Plotinus theory.`

`I explained this already to you, but you keep adding metaphysical`

`stuff which don't exist.`

Only ultrafinitist denies AR.Wrong. Anti realists deny it. I have pointed this out many times. You think the only debate is about the minimal set of mathematical objects, and that is not the only debate. Anti realists can accept a maximal set of objects, with the proviso that their existence is fictive and not real existence

`I am agnostic on all notion of existence. All, except my own`

`consciousness here and now. I suggest a theory, and derive`

`consequences in that theory.`

AR+, the idea that we don't need more than AR, in this setting, is a consequence of the math. From 'outside' the tiny effective universal sigma_1 complete set is enough. from inside, even mathematicalism is not enough (it is more 'theologicalism').The ontological status of mathematical objects is a area of contention in metaphysics, and not straightforwardly proven by mathematics itself.With comp, you don't need more than the part on which almosteverybodyagrees: arithmetical realism.Anti realists do not agee on the real existence of any part. There are no pixies at all, not just a few pixies.

`If you believe in prime numbers, and if you are patient and good`

`willing, I can explain that there are all universal numbers, and why`

`assuming comp that's enough and that's necessary to solve the white`

`rabbit problem. And that postulating physical laws miss the`

`epistemological existence of the qualia.`

`The basic ontology is not important. If you take less than a universal`

`system (like numbers, combinators, ...) you don't have enough for`

`comp, if you take more you miss the qualia.`

`No problem with a formalist interpretation of all this. Actually S4Grz`

`formalize at the meta-level what the machine can uderstand to be non`

`formalisable (like consciousness).`

The engineers, the scientists, most philosophers. Except for Thorgny Tholerus I never met an ultrafinitist. You don't have to decide if numbers are idea of the mind or sort of angel in Plato Heaven. With comp the very idea of number will itself be a number, a sort of second order number, relative to universes (universal numbers).ULtrafinitism has nothing to do with it. For formalists no number exists. They have no prejudice about any kind,

`If comp is false because, according to you 7 does not exist, then it`

`is your problem.`

`I told you that I am working in a theory, which is neutral on those`

`question. Formalist have normally less problem with a tiny sigma_1`

`arithmetic than with the real or complex numbers.`

`I just don't believe you don't believe in seven. You confuse`

`'immaterial' with 'inexistent'.`

`If you don't believe in seven, do you still believe in the formal`

`expression s(s(s(s(s(s(s(0))))))) ?`

http://en.wikipedia.org/wiki/Philosophy_of_mathematicsAnd you cannot refute an argument by anticipating a refutation.So ifyou have a refutation of MGA you should present it.See Colin Klein;s refutation of Maudlin's Olympia.We have already discussed this and Colin Klein does not touch the movie graph argument.Then you had better stop saying the MGA and Olympia are equivalent

`The movie graph *argument*, is not attacked by Klein. Klein attacks`

`the Olympia *argument*.`

`When I say that Olympia and MGA are equivalent, I am talking about the`

`conclusion, not about the arguments leading to the conclusion.`

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.