PHIL-125 Lecture Notes - Lecture 11: Venn Diagram, Contraposition
Document Summary
An argument whose invalidity results from the claim of existence made in conclusion without the matching claim of existence made in premise. An existential fallacy occurs when you only assume something to exist in the conclusion, and not in the premise. You are assuming something to exist in the conclusion but not in the premise. P = decent people ns = dishonest people np = indecent people. Note that the ns and np are the complements of s and p. they are no opposites; if you are an opponent (s), being the complement of opponent (ns) does not make you an ally or proponent. It simply makes you not an opponent, since there are multiple ways for someone not to be an opponent. Some p are not s. (invalid, fallacy of illicit conversions) (valid and logically equivalent) (valid and logically equivalent) (invalid, fallacy of illicit conversions)