[FOM] Godel Sentence

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Karlis Podnieks writes:

 >Thus, since Godel never proved the consistency of a serious formal theory,
 >his results are useless when discussing "true, but unprovable" sentences.

  On the contrary, they are most useful! It is from Godel's theorem we
learn that e.g. "PA is consistent" is unprovable in PA if PA is
consistent. Coupling this with the trivial result that PA is consistent, we
get an example of a true sentence in the language of PA which is
unprovable in PA.

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