Modus tollens

Modus tollens is a valid form of logical reasoning that can be summarized as follows: If we have two statements: 1. If \( P \) then \( Q \) (this is a conditional statement). 2. Not \( Q \) (the negation of the second part of the conditional). From these two statements, we can conclude: 3. Therefore, not \( P \) (the negation of the first part of the conditional).