Philosophy and Logic | Timothy Williamson | Methods of Philosophy: Lecture 6

Part of Prof. Timothy Williamson’s ten-lecture series ’Methods of Philosophy’, organised by Prof. Chen Bo of Peking University, which sponsored and hosted the lectures. ABSTRACT Many philosophers regard the central method of argument in philosophy as deduction, where the premises are logically inconsistent with the denial of the conclusion. Of course, this immediately raises the question of what supports the argument’s premises. Typically, the answer is that they are supported by abduction, a non-deductive form of argument. But this does not mean that philosophy does not need deduction, for it is often the means by which the consequences of a philosophical theory are drawn out, as they must be for the theory to be abductively assessed. Another challenge to the role of deduction in philosophy is that many principles of logic are philosophically controversial, contrary to the assumption that logic is a sort of neutral referee for substantive disagreements. In fact, virtually every proposed principle of logic h