On 17 Jul 2011, at 20:28, meekerdb wrote:

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On 7/17/2011 10:11 AM, Bruno Marchal wrote:On 15 Jul 2011, at 18:41, meekerdb wrote:On 7/15/2011 2:15 AM, Bruno Marchal wrote:Numerology is poetry. Can be very cute, but should not be takentoo much seriously. Are you saying that you disagree with thefact that math is about immaterial relation between non materialbeings. Could you give me an explanation that 34 is less than 36by using a physics which does not presuppose implicitly thenumbers.|||||||||||||||||||||||||||||||||||||||| ||||||||||||||||||||||||||||||||||||||||||Nice, indeed. We do agree that 34 is less than 36, and what thatmeans.I am not sure your proof is physical thought. Physics has been veryuseful to convey the idea, and I thank God for not having made mycomputer crashed when reading your post, but I see you onlyteleporting information. That fact that you are using the physicalreality to convey an idea does not make that idea physical.I was expecting a physical definition of the numbers.Of course there is no physical definition of the numbers because theusual definition includes the axiom of infinity.

`You don't need the axiom of infinity for axiomatizing the numbers. The`

`axiom of infinity is typical for set theories, not natural number`

`theories. You need it to have OMEGA and others infinite ordinals and`

`cardinals.`

As finite beings we can hypothesize infinities.

`Yes, but we don't need this for numbers. On the contrary, the`

`induction axioms are limitation axioms to prevent the rising of`

`infinite numbers.`

By thinking that I can understand your proof, you are presupposingmany things, including the numbers, and the way to compare them.On the contrary I think you (and Peano) conceived of numbers byconsidering such such examples. The examples presuppose very little- probably just the perceptual power the evolution endowed us with.

`That is provably impossible. No machine can infer numbers from`

`examples, without having them preprogrammed at the start. You need the`

`truth on number to make sense on any inference of any notion.`

So it is a funny answer, which did surprise me, but which avoidsthe difficulty of defining what (finite) numbers are.It *is* a theorem in logic, that we can't define them "univocally"in first order logical system. We can define them in second orderlogic, but this one use the intuition of number.If you agree that physics is well described by QM, an explanationof 34 < 36 should be a theorem in quantum physics,I'm sure it is. If you add 34 electrons to 36 positrons you get twopositrons left over.Physics is not an axiomatic system.

`That is the main defect of physics. But things evolve. Without making`

`physics into an axiomatic, the whole intepretation problem of the`

`physical laws will remain sunday philosophy handwaving. Physicists are`

`just very naïve on what can be an interpretation. The reason is they`

`"religious" view of the universe. They take it for granted, which is`

`problematic, because that is not a scientific attitude.`

Physicists use mathematics (in preference to other languages) inorder to be precise and to avoid self-contradiction.

`That is the main error of the physicists. They confuse mathematics`

`with a language. Even Einstein was wrong on this. Wheeler, Deutsch and`

`Penrose are already far less wrong on this. Mathematics is independent`

`of language. We can be wrong on this because mathematics is highly`

`dependent on language when we want to *communicate* mathematical`

`facts. Logic can help to make this precise. But when logic is studied`

`superficially, it can aggravate the confusion, due to the role of the`

`formal languages.`

That doesn't mean that physics is mathematics.

`A good point. Even with comp, physics is not mathematics, nor is`

`theology pure mathematics. But with comp, math plays a more`

`fundamental role, and in a sense, theology (of a provably correct`

`machine) is a branch of arithmetic. But it happens we cannot know that`

`for ourselves. This is coherent with the fact that the proposition "I`

`am conscious" cannot be made mathematical. The first person is, from`

`its point of view, beyond math (and physics).`

That |||||| is fewer than ||||||| is a fact about the world,

... about reality. OK. The word "world" is ambiguous.

that 5<7 is a theorem in mathematics which may be interpreted as adescription of that fact.

`I would say that it is a justification, or explanation of that fact.`

`The description is still another thing.`

But when talking philosophy we should be careful to distinguishfacts from descriptions of the facts.

`And to distinguish description and justification-proof, which can`

`themselves be described, like in logic-metamathematics.`

but the problem here is that quantum physics assumes real numbersand waves (trigonometrical functions), and that reintroduce thenumbers at the base.If it were an axiomatic system it would have lots of axioms(probably including Peano's) but it isn't. I'm not sure axioms are"assumptions" though.

`I use assumption in the sense that we cannot prove them (in the theory`

`under consideration).`

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.