PP201 Lecture Notes - Jorge Luis Borges, Modus Ponens, Modus Tollens
Document Summary
Today our concern is to understand the basic structure of arguments and how they work. Arguing is ubiquitous and is an essential aspect of our daily lives. Some arguments are serious and concern matters of life and death, while others are just silly. An argument consists of a set of statements (premisses) that together support or establish the truth of another statement (the conclusion). The conclusion is said to follow from the premisses. We can infer the conclusion from the premisses. Inference is a rational relation between statements or sets of statements. To infer b from a is to hold b true so long as a is true. In other words, if we assume a is true it is rational to assume b is true. Assuming it is true that france is a republic and the weather is fine we can infer that the weather is fine, i. e. , hold it to be true that the weather is fine.