Re: Simple yet Profound Metatheorem

Charlie-Boo says...

>New Question: Just curious - is there even a wff such that you can
>prove it to be intuitionistically valid but I can't prove the wff
>using case analysis?

No, it's the other way around. There are formulas that are provable
using truth tables (case analysis) but are not provable
intuitionistically. The examples are

Excluded Middle: A or ~A
Pierce's Law: ((P -> Q) -> P) -> P

--
Daryl McCullough
Ithaca, NY

.

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