Abstract

In recent and not so recent years, fallacy theory has sustained numerous challenges, challenges which have seen the theory charged with lack of systematicity as well as failure to deliver significant insights into its subject matter. In the following discussion, I argue that these criticisms are subordinate to a more fundamental criticism of fallacy theory, a criticism pertaining to the lack of intelligibility of this theory. The charge of unintelligibility against fallacy theory derives from a similar charge against philosophical theories of truth and rationality developed by Hilary Putnam. I examine how Putnam develops this charge in the case of the conception of rationality pursued by logical positivism. Following that examination, I demonstrate the significance of this charge for how we proceed routinely to analyse one informal fallacy, the fallacy of petitio principii. Specifically, I argue that the significance of this charge lies in its issuance of a rejection of the urge to theorise in fallacy inquiry in general and petitio inquiry in particular. My conclusion takes the form of guidelines for the post-theoretical pursuit of fallacy inquiry