It has often been argued that since all sound arguments are either inductive or deductive, and philosophical arguments are neither, no philosophical arguments are sound. In his recent book Philosophical Reasoning, Passmore attempts to show that sound philosophical arguments are possible. He does this not by attacking the premise that all sound arguments are either inductive or deductive, but rather by attacking the premise that philosophical arguments are neither deductive nor inductive. In fact, he asserts, “Philosophical reasoning, if it is (...) to be valid at all, must be deductive in its formal structure.” Passmore’s point is that deductive arguments are by no means confined to mathematical reasoning. Mathematics uses deductive inference in one way, and philosophy in another. Passmore does not attempt to define this alleged difference between the way mathematics uses deductive inference and the way philosophy uses it. Instead he gives examples of kinds of argument that are often used in philosophy and seldom elsewhere. One such kind of argument consists in pointing out that one’s opponent has begged the question. Another is the so-called ‘infinite regress’ argument. Again, the kind of argument that a philosopher is using when he ‘reminds’ his interlocutor of a principle that he has presumably forgotten or overlooked in the process of formulating his philosophical position is fairly common in philosophy although not frequently used in other fields. Other sorts of argument cited by Passmore as basically philosophical are ‘verbal analysis’ and ‘self-refutation’. The considerations that Passmore has in mind in characterizing all of these arguments as philosophical are stylometric. By this I mean that what motivates him to classify an argument as philosophical is not any property attaching to the argument itself, but rather the fact that it occurs for the most part in philosophical contexts. He explicitly states that other kinds of arguments, including those mainly used in mathematical contexts, can occur in philosophy, and that the arguments which he classifies as philosophical can occur in non-philosophical contexts. (shrink)