In need of the all-out revision of symbolic logic

From: Eukie_M_SHIRAISHI <ms.eurms@xxxxxxxxx>
Date: Mon, 28 Apr 2008 19:59:32 -0700 (PDT)

In the Fregean Theory of Logic (the standard theory of logic in the
20th century),
“p implies q” has had been defined to mean “not-p or q”.

Here let P be “A lion is a mammal” and Q be “A lion and a whale are
both mammals”
It is clear that Q implies P but P does not imply Q.
Hence “P implies Q” is a falsity.
On the other hand, “not-P or Q” is a truth.
Therefore, it is a mistake to define “p implies q” to mean “not-p or
q”.

Since implication is one of the most fundamental concepts in logic,
all-out revision
is needed in the Fregean Theory of Logic.

Have a look at the following Web site:- <http://www.age.ne.jp/x/eurms/
PNG/Key/Honron-2.html#02-2>
.

Follow-Ups:
- Re: In need of the all-out revision of symbolic logic
  - From: Frederick Williams
- Re: In need of the all-out revision of symbolic logic
  - From: sarabt1

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