PHI 1101 Lecture Notes - Logical Form, Multiple Choice, Syllogism

• School: University of Ottawa
• Department: Philosophy
• Course: PHI 1101
• Professor: Mark Brown

Document Summary

There are four standard forms of categorical statements: All s and p (all cats are carnivores) No s are p. (no cats are carnivores) Some s are p (some cats are carnivores) Some s are not p (some cats are not carnivores) No a-students are slackers: venn diagram of 2 circles. Shade out the all students without touching the overlap: venn diagram of 2 circles. Some professors are not mean. (negation: venn diagram of 2 circles with an asterisk (*) in the overlap area, venn diagram of 2 circles with the asterisk is in the professor circle. A valid categorical syllogism is such that if its premises are true, then its conclusion must be true. We can check the validity by using a venn diagram. If, after representing the premises, the conclusion is already represented on the diagram, then the argument is deductively valid. Note: you only ever diagram the premises, you never ever diagram the conclusion.