Re:MIT Ends Elsevier Negotiations
by c3534l on Friday June 12, 2020 @01:54AM
(#23496439)
Yes. In classical logic, p OR !p is always true. You have to add these axioms to get classical logic. Intuitionistic logic doesn't have that. p OR !p is not necessarily true in intuitionistic logic.
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> A and not A are not necessarily contradictions
Nobody was saying p OR !p is necessarily true. The argument was about p AND !p. It really seems to me like you're confusing AND and OR...
The intuitionist will accept that "A and not A" cannot be true https://en.wikipedia.org/wiki/Intuitionism#Truth_and_proof