PHL145H5 Lecture Notes - Lecture 5: Categorical Proposition, Inductive Reasoning, Syllogism
Document Summary
There are 3 different forms of inductive reasoning. An inductive argument is good if, and only if, the truth of the premises gives a reason to believe the conclusion, or (roughly equivalent) if the truth of the premises raises the probability of the conclusion. An inductive argument is cogent if, and only if, it is good and its premises are in fact true. Categorical propositions are about categories of things. Quantified categorical propositions say something about a certain amount of members of a category of things. Jack shakes a large opaque basket filled with 4,000 black and red cubes, reaches in without looking, and grabs 500. He counts the reds, sees that he has 450, and then on this basis infers that roughly 90% of the cubes in the basket are red. P1: cube1, cube2, , cube500 are all cubes in the basket. P2: 90% of cube1, cube2, , cube500 are red.
