PHIL 101 Lecture 24: Intro to Logic, Lecture 24

• School: University of San Diego
• Department: Philosophy
• Course: PHIL 101
• Professor: agule

Document Summary

Take premises and conclusion and lay them out horizontally. There is only one way for the premise to be true or the conclusion to be false. D v (e * f) ~e / d. D is false e is false e must be false d has to be f. E * f must be true for the v statement to be true, which is not possible, so the argument must be valid. Ex 2: (c > d) > (d > b) T t t f d must be true c must by true and b must be false. So the rst premise is false, so this argument must be valid (a v b) > (c * d) Since the rs argument must actually be false, the argument is actually false (r * c) > ~e. Since the rst premise cannot be made true, the argument must be valid since the argument is inconsistent.