Logic and Proof Principles Il Cleaver Picture Modus Tollens What does this comma mean, does it mean "and"? Does it mean that either P=>Q or -Q1 = -P? If both (P=>Q. -Q) follow from -p, this means that ((P=>Q, -Q)) = -P is True. Right? l f both (P=>Q, -Q) DONT follow from -p, this means that (Pe>Q, -Q)) = -P is False. Right? wak akt Another look at proof by contradiction {P=Q), -adrup P Q Pasalip na Dy not ok! Dook Can someone explain why {(P =) Q), 7Q Erp please ? OK