PHI 1101 Lecture Notes - Lecture 9: Modus Tollens, Modus Ponens, Deductive Reasoning

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

Document Summary

* an argument intended to provide logically conclusive support for its conclusions. * defining characteristic is that it is either valid or invalid. * a deductive argument is intended to provide conclusive support for its conclusion. * the structure or form of some arguments is deductive. * when arguments are structured in a certain way they are good since they guarantee their conclusion. * if the premises are true, then the conclusion must also be true, and we can describe the argument as being valid. * arguments that are valid can be described as having: * the only combinations of premises and conclusion that can be considered to be invalid is true premises and a false conclusion. * that if its premises were true then the premises would guarantee the conclusion. But the structure of the argument is valid. Every province west of ontario is famous for harvesting lobster. Thus, new brunswick is famous for harvesting lobster.