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- Newsgroups: sci.math
- Path: sparky!uunet!convex!darwin.sura.net!spool.mu.edu!agate!stanford.edu!rock!taco!auerbach
- From: auerbach@ncsu.edu (David D Auerbach)
- Subject: Re: Logic and Mathematicians (quite long)
- Message-ID: <auerbach.721856286@news.ncsu.edu>
- Sender: news@ncsu.edu (USENET News System)
- Organization: North Carolina State University
- References: <1992Nov13.090126.7142@jarvis.csri.toronto.edu> <1992Nov15.150408.18663@email.tuwien.ac.at>
- Distribution: sci.math
- Date: Sun, 15 Nov 1992 19:38:06 GMT
- Lines: 21
-
- I won't quote this thread, which has gotten quite lengthy, and turned into
- a discussion of what exactly certain logicians, chiefly Godel, showed. I
- have a few cavils with some assertions that went by. The 2nd
- Incompleteness Theorem is not a simple corollary of the 1st; if it were
- Godel would have proved it in his paper. He sketched it. Proving it is not
- trivial and requires stronger assumptions than G1.
- There is a sizable literature on whether G1, G2 or neither refute
- Hilbert's Program or modified Hilbert's Programs. For such arguments the
- technical results alone do not suffice--one needs the premises that relate
- such purely mathematical results to the epistemology. The issues are not
- as simple as the remarks in the thread would indicate. (I think Hilbert's
- Program *is* refuted, but it takes a longer argument than pointing at G2 ).
- Finally there was a tone in the thread that Godel numbering is simply a
- matter of assigning numbers 1-1 to syntactic entities and after that it is
- a simple diagonal argument. Not so; there is the tender matter of showing
- that sequences of *arbitrary* length can be coded up in an elementary
- manner. One of Godel's many insights was that this was what was needed and
- then doing it. (In his original proof this is where the Chinese Remainder
- THeorem comes in). What is amazing about the original paper is the
- surefootedness with which he covered all the bases in an area where he
- basically had to invent modern standards of clarity and rigor.
-