Logical Proofs With Equivalences

Enlarge your ability to prove arguments with natural deduction by studying nine equivalences—sentences that are t... (more)

Enlarge your ability to prove arguments with natural deduction by studying nine equivalences—sentences that are truth-functionally the same. For example, double negation asserts that a sentence and its double negation are equivalent. "It is not the case that I didn’t call my mother,"means that I did call my mother. (less)