Philosophy 1200 Lecture Notes - Lecture 28: Modus Tollens, Formal Language, Logical Form

• School: Western University
• Department: Philosophy
• Course: Philosophy 1200
• Professor: Eric Desjardins

Document Summary

Now that we can translate arguments into our formal language, we can use truth tables to test the validity of natural language arguments. (239) an all powerful god would not allow suffering in the world. Since there is suffering, god does not exist. If and all powerful god exists, then there would be not suffering in the world. Since s is the same as ~~s we can see this is just an instance of the valid argument form modus tollens. But the hill will be icy or it won"t. So if it snows the hill won"t be icy. Another way to demonstrate that an argument is invalid is to provide another argument having the same form, in which the premises are true and the conclusion is false. This second argument is called a counterargument, or counterexample to the argument form, an absurd example or a logical analogy.