#concept
godelβs 2 incompleteness theorems are concerned with >> the limits of provability in formal axiomatic theories.
Any system that can talk about itself and its own consistency is necessarily inconsistent.
First Incompleteness Theorem >> βAny consistent formal systemΒ FΒ within which a certain amount of elementary arithmetic can be carried out is incomplete; i.e., there are statements of the language ofΒ FΒ which can neither be proved nor disproved inΒ F.β [1]
Second Incompleteness Theorem >> βAssumeΒ FΒ is a consistent formalized system which contains elementary arithmetic. Then F does not prove the consistency of Fβ [2]
True or False: Godelβs first theorem shows there are truths that canβt be proved. Explain ? False. Incompleteness theorem doesnβt deal with provability in an absolute sense, but rather the derivability in a specific formal system. Statement X may be unprovable in formal system A but provable in formal system B.
According toΒ GΓΆdelβs incompleteness theorems, the statement that Peano Arithmetic (PA) is consistent, in its guise as a number-theoretic statement (given the technique of godel numbering) ? cannot be derived in PA itself. godel numbering is used to prove these theorems.
References
Notes
1st theorem: not complete
- any sentence can be represented w a godel number
- any proof can be represented w a godel number
- the proof referring to itself cannot be represented as a godel number
- g: there is no proof with the statement godel g
2nd: canβt prove consistency
my hot takes
butβ¦you kinda got to accept formal system of peano arithmetic, to accept godel numberingβ¦ i just think a formal system itself is flawedβ¦logical systemβ¦