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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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 camgirls@hush.com Posts: 12 Registered: 4/8/11
Re: If ZFC is a FORMAL THEORY ... then what is THEOREM 1 ?
Posted: Oct 12, 2012 8:52 PM

On 13 Oct, 10:45, rich...@cogsci.ed.ac.uk (Richard Tobin) wrote:
>
>  <camgi...@hush.com> wrote:

> >> THERE IS, however, an algorithm that CONFIRMS that a formula is
> >> logically valid WHEN IT IS.

> >so why can't you do brute force lexicographically on ALL formulas and
> >output

>
> >VALID
> >NOT VALID

>

>
> Because there isn't an algorithm that confirms that a formula is
> invalid when it is.
>
> -- Richard

[GG]
THERE IS, however, an algorithm that CONFIRMS that a formula is
logically valid WHEN IT IS.

Use this!

if (valid(formula)) write (formula + " is valid")
else write (formula + " is not valid")

What are you saying, valid() doesn't halt when the formula is invalid?

Herc

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