On Wed, 19 Jul 2006 19:47:02 -0600, Virgil <email@example.com> wrote:
>In article <firstname.lastname@example.org>, > Lester Zick <DontBother@nowhere.net> wrote: > >> On Wed, 19 Jul 2006 14:47:00 -0600, Virgil <email@example.com> wrote: >> >> > You have not read my reference to " logical tautologies" correctly. >> > >> >If, for example. "P and not P" would qualify as "false" does your >> >gobledegook require its negation, "P or not P", to be true? >> >> "P and not P" is only universally false because it provides no >> mechanical basis for alternatives since any "not (P and not P)" >> converts into itself "not P and P". > >Not in any respectable logic it doesn't. According to de Morgan's laws, >"not (P and not P)" is logically equivalent to "P or not P".
It may be equivalent to lots of things. The issue is whether it converts into itself mechanically.
>> So there is no alternative in >> strict mechanical terms because "P or not P" is not always true if P >> itself contains a self contradiction because P and "not P" are the >> same. > >If P contains a contradiction, doesn't that make P false? In normal >logic, that would make (not P) true.
It makes them the same.
>> See if the above impresses you even a little. > >Not even.