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Topic: If ZFC is a FORMAL THEORY ... then what is THEOREM 1 ?
Replies: 39   Last Post: Oct 14, 2012 11:56 PM

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 george Posts: 800 Registered: 8/5/08
Re: If ZFC is a FORMAL THEORY ... then what is THEOREM 1 ?
Posted: Oct 13, 2012 8:16 PM

On Oct 13, 4:30 pm, Graham Cooper <grahamcoop...@gmail.com> wrote:
> You still owe me some BASE THEOREMS, otherwise all your "proofs" are
> Oracular.

No, I don't. I can just say that rule "EM" (that is what I choose to
call it)
allows me to infer P V ~P *FROM*NOTHING*.
Moreover, I can call the universal generalization of that (with P as
the variable) an inference rule (if I want to)
and say that if P is ANY WFF WHATSOEVER in the first-order langauge I
am using, then
P V ~P is inferred, as the conclusion of this inference rule, and as a
theorem,
FROM NOTHING.
That does NOT make anything "oracular" and it does NOT make anything a
"logical axiom".

I can [AND DO] JUST say that it is an inference rule that any
instance of a propositional tautology is a theorem.

Date Subject Author
10/5/12 Graham Cooper
10/5/12 Frederick Williams
10/7/12 Charlie-Boo
10/5/12 Graham Cooper
10/5/12 Frederick Williams
10/5/12 Graham Cooper
10/7/12 Graham Cooper
10/8/12 Graham Cooper
10/9/12 Graham Cooper
10/11/12 Graham Cooper
10/12/12 Graham Cooper
10/12/12 Graham Cooper
10/12/12 camgirls@hush.com
10/12/12 Richard Tobin
10/12/12 camgirls@hush.com
10/13/12 george
10/13/12 Graham Cooper
10/14/12 george
10/13/12 Graham Cooper
10/13/12 george
10/13/12 george
10/13/12 Graham Cooper
10/14/12 Graham Cooper
10/14/12 Graham Cooper
10/14/12 Graham Cooper
10/5/12 Scott Berg
10/5/12 Curt Welch
10/6/12 Mike Terry
10/6/12 Graham Cooper