1. It is very closely related to the rule of inference modus tollens . 2. The falsification of statements occurs through " modus tollens ", via some observation. 3. The history of the inference rule " modus tollens " goes back to antiquity. 4. So then modus tollens wouldn't be included as an inference rule in constructive logics? 5. The first to explicitly describe the argument form " modus tollens " were the Stoics. 6. Modus ponens is closely related to another valid form of argument, " modus tollens ". 7. In instances of " modus tollens " we assume as premises that p ?! q is true and q is false. 8. Popular rules of inference in propositional logic include " modus ponens ", " modus tollens ", and contraposition. 9. This is often called the " law of contrapositive ", or the " modus tollens " rule of inference. 10. The inference rule " modus tollens " validates the inference from P implies Q and the contradictory of Q to the contradictory of P.
