PHI 1101 Lecture Notes - Lecture 9: Categorical Logic, Propositional Calculus, Obversion

• School: University of Ottawa
• Department: Philosophy
• Course: PHI 1101
• Professor: Sascha Maicher

Document Summary

Categorical logic: the way which humans make claims about classes of things. They have a subject and a predicate (verb). First space is the subject of the claim, second space is the predicate of the claim. Categorical a and e claims are universal claims. These two claims are universal claims because they talk about all the members of that class. The second type of a categorical claim is a particular claim. Particular claims talk about some members of a class. A. all wolves are mammals: e claim. no members of a class are. Another example: no dragons are alive: i claim. Some members of the class: o claim. Affirmative claim: something is something ( a and i ) Negative claim: something isn"t something ( e and o ) Example:the only logical fans are barca fans -> same thing. The word only used by itself introduces the predicate term of an a claim.