I think his discussion of “aristotelian categoricals” may shed light on other problems in ethical theory, specifically the possibily of virtue ethics.

Well, for what it’s worth this is one of the explicit purposes of the philosophical work that I’m drawing on. Philippa Foot has the best investigation I know of in her book Natural Goodness, and puts the logical status of Aristotelian categoricals front and center in her account of why a broadly Aristotelian virtue theory can succeed in solving a number of standing problems concerning ethics and rationality; Thompson’s essay explicitly aims at, among other things, clearing some of the logical ground for an explanation of what he finds to be right in Foot’s work, and in some similar remarks on ethics by Elizabeth Anscombe.

It’s good stuff; if more people in applied ethics would apply it, then we might see some more interesting and serious work on questions like those surrounding ethical vegetarianism.