12 November 2021, Cool Logic, Tibo Rushbrooke

In his seminal 1936 paper "On the Concept of Logical Consequence", Tarski provides a notion of logical consequence which has become standard in analytic philosophy today. Tarski argues that logical consequence is independent of the meanings of non-logical terms, on the grounds that a logical inference cannot rely on any empirical knowledge of the objects referred to. Accordingly, he defines a logical consequence relation which is insensitive to the meanings of the non-logical vocabulary. In this talk, I will closely scrutinise Tarski’s original reasoning. I will then give an alternative notion of logical consequence in natural language, which is entirely sensitive to the meanings of the terms involved. I argue that the alternative notion is both interesting and fruitful, in that it captures certain inferences not reckoned as ‘logical’ by the traditional notion, thus broadening the scope of logic.