Abstract

The conviction that argument plays an essential role in philosophy seems to be a rather widespread one. At the same time, however, there is no explicit agreement on what may count as a reason for this conviction, neither is there explicit agreement on what it is for a philosophical argument to be good. Henry W. Johnstone jr. tried to provide a positive answer to these questions, by sketching a general theory of philosophical argumentation. Johnstone's main claim is that philosophical arguments typically are "ad hominem" arguments, in that they rely on premises accepted by some philosopher and are intended to show the undesirable logical consequences of these premises. According to Johnstone there may be valid philosophical "ad hominem" arguments.