PHI 1101 Lecture Notes - Lecture 9: If And Only If, Logical Biconditional, Logical Form

• School: University of Ottawa
• Department: Philosophy
• Course: PHI 1101
• Professor: Vincent Bergeron

Document Summary

They could be very relevant or they could be a little relevant. A premise is relevant to a conclusion if it provides support at all. A set of premises is adequate if they provide enough support to make it reasonable to accept the conclusion. A strong conclusion requires strongly adequate support. The basic here is because it is not going to be an advanced section on formal or symbolic logic. Bolzano"s definition of validity has 2 steps. Valid argument form: an argument form is said to be valid if and only if no instance of the form has all true premises and a false conclusion. It is not possible for the premises to be true and the conclusion false. An instance is a particular argument that has the form in question. Valid argument: an argument is valid if and only if it is an instance of a valid form. Whenever you have a particular argument, if that argument is valid.