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Neither have the books yet been closed on the antinomy, nor has
agreement on its significance and possible solution yet been reached." -
(Abraham Fraenkel)
Using the L?wenheim-Skolem Theorem, we can get a model of ZF set theory which contains only a countable number of objects. However, it must contain the aforementioned uncountable sets. This appears to be a contradiction, since the uncountable sets are subsets of the (countable) domain of the model.
A widely held interpretation is that of Thoralf Skolem himself. He believed that LST showed a relativity in some of the fundamental concepts of set theory. Uncountable cardinalities in particular have no meaning apart from specific sets of axioms. A set may be uncountable within a certain formal system and countable when viewed from the standpoint of an unintended model of that system. This means that there simply are no sets whose cardinality is absolutely uncountable. For many, this view guts set theory, arithmetic, and analysis. It is also clearly incompatible with mathematical Platonism which holds that the real numbers exist, and are really uncountable, independently of what can be proved about them.
"I believed that it was so clear that axiomatization in terms of sets was not a satisfactory ultimate foundation of mathematics that mathematicians would, for the most part, not be very much concerned with it. But in recent times I have seen to my surprise that so many mathematicians think that these axioms of set theory provide the ideal foundation for mathematics; therefore it seemed to me that the time had come for a critique." - ([[Skolem]"The Bulletin of symbolic logic" Vol.6, no 2. June 2000, pp. 147
G?del didn't rely on the notion
of truth
Godel did is find a general method that enabled him to take any theory T
strong enough to capture a modest amount of basic arithmetic and
construct
a corresponding arithmetical sentence GT which encodes the claim 'The
sentenceGT itself is unprovable in theory T'. So G T is true if and only
if T can't prove it
If we can locate GT
, a Godel sentence for our favourite nicely ax-
iomatized theory of arithmetic T, and can argue that G T is
true-but-unprovable,
G?del's first incompleteness theorem, perhaps the single most celebrated result in mathematical logic, states that:
For any consistent formal, recursively enumerable theory that proves
basic arithmetical truths, an arithmetical statement that is true, but not
provable in the theory, can be constructed.1 That is, any effectively
generated theory capable of expressing elementary arithmetic cannot be
both consistent and complete.
I am wondering if you mean that maths is in trouble because formulae are [1]based on the incompleteness theorem and that the formula is incorrect in itself or [2] that the theory the incompleteness theorem presents (especially in combination with skolems paradox which helps point just that out) makes math "obsolete" in a way?
G?del's first incompleteness theorem, perhaps the single most celebrated result in mathematical logic, states that:
For any consistent formal, recursively enumerable theory that proves basic arithmetical truths, an arithmetical statement that is true, but not provable in the theory, can be constructed.1 That is, any effectively generated theory capable of expressing elementary arithmetic cannot be both consistent and complete.
Wasn't Godel's theorem debunked? Or was that Kant?
GODEL'S INCOMPLETENESS THEOREM. ENDS IN ABSURDITY OR MEANINGLESSNESS GODEL IS A COMPLETE FAILURE AS HE ENDS IN UTTER MEANINGLESSNESS CASE STUDY IN THE MEANINGLESSNESS OF ALL VIEWS
