RE Bad terms in seq A108719? (last one)
Tautócrona
tautocrona at terra.es
Wed Nov 16 01:04:38 CET 2005
----- Original Message -----
From: "Tautócrona" <tautocrona at terra.es>
The flaw is, of course, in 5.). If we have that q --> -p then we know that Q is a subset
of -P, not the other way around. So we can not infer from q --> -p and p & q that we have
p & -p because P & Q is a set smaller than P & -P (I hope the logic-set theory analogy is
clear for anyone). I applied a false modus.
=================================
Oops! Forget (and forgive) entirely my last thread. I must have been lobotomyzed or
something.
Obviously if we have q, and we have q --> -p, then we have -p. This' real basic logic. The
flaw was in 4., we can say that there's "at least one element that..." in the empty set. I
was confunded by an intuitive pseudo-analogy I thought was right between formal logic and
set theory.
Regards. Jose Brox
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