Against Counterexamples to Hypothetical Syllogism
Issue: • Author/s: Eddie W.L. Cheng
Topics: Epistemology, Philosophical logic, Philosophy of language, Philosophy of logic
A hypothetical syllogism with three conditional propositions (hereinafter HSc) is considered invalid according to the ordinary discourse counterexamples in the existing literature. In this paper, I argue that such counterexamples cannot verify the validity of HSc. The conditional propositions in these arguments are questionable, whether that is indicative or counterfactual HSc. The arguments are considered invalid not because HSc is invalid by itself, but because there is a mismatch between the antecedent of one premise and the consequent of another premise (i.e. a violation of the common part of both…