  So how, if at all, does D1 entail all the things that Socrates apparently makes it entail in 151–184? And does Plato think it has all these entailments? Evidently the answer to that depends on how we understand D1. In particular, it depends on the meaning of the word aisthêsis, “perception,” in D1. If the slogan “Knowledge is perception” equates knowledge with what ordinary speakers of classical Greek would have meant by aisthêsis, then D1 does not entail Protagoras’ and Heracleitus’ views. In the ordinary sense of aisthêsis, there are (as just pointed out) too many other possible ways of spelling out D1 for the move from D1 to Hm to be logically obligatory. But if the slogan “Knowledge is perception” equates knowledge with what Protagoras and Heracleitus meant by aisthêsis, D1 does entail Protagoras’ and Heracleitus’ views. Of course it does; for then D1 simply says that knowledge is just what Protagoras and Heracleitus say knowledge is.