SSH 105 Lecture Notes - Lecture 7: Murder 2, Deductive Reasoning

• School: Ryerson University
• Department: Social Sciences and Humanities
• Course: SSH 105
• Professor: Klaas Kraay

Document Summary

This is the notion of a valid argument . Deductive argument: intends to provide logically conclusive support for the conclusion ambitiously in that the argument must be true. Deductive validity: an argument is deductively valid if and only if it is impossible for all the premises to be true and the conclusion false whilst also possessing the logical connection between premises and conclusion. If all the premises were true, then the conclusion would have to be true as well. > in a world where the premises are all true, then the conclusion is guaranteed to be true as well. Ex: all bachelors are unmarried, ivan is a bachelor, ivan is unmarried (from 1,2) All the premises above can be said to all be false but the argument retains validity . False premises, false conclusions: all human beings can fly, all red things can fly, all human beings are red.