Perception, then, is always of that which exists and, since it is knowledge, cannot be false. Theaetetus So it seems. Socrates By the Graces! I wonder if Protagoras, who was a very wise man, did not utter this dark saying to the common herd like ourselves, and tell the truth19 in secret to his pupils. [152d] Theaetetus Why, Socrates, what do you mean by that? Socrates I will tell you and it is not a bad description, either, that nothing is one and invariable, and you could not rightly ascribe any