Date: Oct 12, 2012 8:52 PM
Subject: Re: If ZFC is a FORMAL THEORY ... then what is THEOREM 1 ?
On 13 Oct, 10:45, rich...@cogsci.ed.ac.uk (Richard Tobin) wrote:
> In article <458567d7-d298-4c8f-af7d-36473f1ae...@n16g2000yqi.googlegroups.com>,
> <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
> >NOT VALID
> Because there isn't an algorithm that confirms that a formula is
> invalid when it is.
> -- Richard
THERE IS, however, an algorithm that CONFIRMS that a formula is
logically valid WHEN IT IS.
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?