# Testing Logical Equivalence

by axellerate
Tags: equivalence, logical, testing
 P: 562 After you have followed micromass's suggestion, the next step can make more sense to you if you contemplate an analogy (I stress that this is a way of thinking: it would not work as a formal proof) all quantifier like a large "and", existence quantifier like a large "or" "and" like "intersection" "or" like "union" deMorgan Laws. Formally, if you are not an intuitionist, you can try playing around with the equivalence between "$\forall$x P" and "~$\exists$x ~P", or between "$\exists$x Q" and "~$\forall$x ~Q" (by the way, it's "per se")