  The first of these deft exchanges struck the Anonymous Commentator as disingenuous: “Plato himself knew that Protagoras’ opinion about knowledge was not the same as Theaetetus’” (Anon, ad loc.). Certainly it is easy to see counter-examples to the alleged entailment. Take, for instance, the thesis that knowledge is awareness (which is often the right way to translate aisthêsis). Or take the thesis that to know is to perceive things as God, or the Ideal Observer, perceives them, and that we fail to know (or to perceive) just insofar as our opinions are other than God’s or the Ideal Observer’s. These theses are both versions of D1. Neither entails Hm, the claim that “man is the measure of all things”; nor the Protagoreanism that lies behind that slogan.