PHIL 210 Lecture Notes - Lecture 1: Modus Ponens, Constructive Dilemma, Law Of Excluded Middle

• School: Concordia University
• Department: Philosophy
• Course: PHIL 210
• Professor: Guillaume Beaulac

Document Summary

The book gives two definitions of an argument. Neither of these definitions identifies arguments with heated disputes between two people. This sense of argument is not what we are interested in for this course. In the first definition an argument is something given by a particular speaker, in a given context, in order to convince an audience of a certain point. The second definition is more idealized, but often very helpful for understanding arguments. An argument is a series of statements (premises) that are intended to lend support to a conclusion. An argument is valid if it is not possible for the premises to all be true and the conclusion false. If stephen harper is a fish, then he spends his life under water. In the example above, the premises imply the conclusion (it is valid). But there is an obvious problem with the argument. Not all of the premises are true (stephen harper is not a fish).