PHIL 105 Lecture Notes - Lecture 7: First-Order Logic, Logical Reasoning, Zucchini

• School: Simon Fraser University
• Department: Philosophy
• Course: PHIL 105
• Professor: Jill Mc Intosh

Document Summary

Rule method cannot be used to test for cogency. It is saying more than some a are b . ( some means at least one ) It is not saying that some a are not b, since most a are b would be true even if. Most of the students in this room are under 50 . This isn"t false if all the students in this room are under 50. Can these claims fit into one of the four standard forms: every a is a b. = all a are b: only a are b. Consider the following two claims: dr. mc owns a van, dr. mc does not own a van. They cannot both be false at the same time: dr. mc"s one and only van is all orange, dr. mc"s one and only van is all green. In conflict? (ask could they both be true at the same time?)