I recall my eventual dissertation supervisor, Bernard Williams, saying to me once that he didn’t think that anyone could do ethics competently without a thorough grounding in logic. I nodded solemnly as if to register agreement, though I had never spent a minute studying logic and didn’t even know what a modus ponens was—in fact, I still don’t, though I know it has something to do with p and q.

Jeff McMahan, in Thomas S. Petersen and Jesper Ryberg (eds.), Normative Ethics: 5 Questions, 2007, p. 69