On ch. 17, "constructing proofs", pg. 130, practice exercises, in C.5 i think there is a typo,
(A or ~B) -> (A -> B) is not a tautology (check for instance here). It would have been, for instance, if the outermost consequent were reversed, to B -> A, having
rzach
commented
4 years ago
On ch. 17, "constructing proofs", pg. 130, practice exercises, in C.5 i think there is a typo,
(A or ~B) -> (A -> B) is not a tautology (check for instance here). It would have been, for instance, if the outermost consequent were reversed, to B -> A, having
(A or ~B) -> (B -> A)
version 2cf987e (2020-08-07)
btw, thanks for all this effort.