For although Theaetetus has enumerated several kinds of knowledge, he has not explained the common nature Jowett1892: 147of them; as if he had been asked, ???What is clay???? and instead of saying, ???Clay is moistened earth,??? he had answered, ???There is one clay of image-makers, another of potters, another of oven-makers.??? Theaetetus at once divines that Socrates means him to extend to all k