We will now study the germ of all these theories in classical Greek criticism. The main lines of classical literary theory are mimetic--they are concerned mostly with the relationship between the work and reality. But in the best work of Plato or Aristotle we can find the elements of future interpretive and structural theories of literature. It is difficult at times to distinguish what is explicitly stated in a particular theory of criticism from what is merely implied, just as it was difficult to draw the line between literary theory and literary criticism. The merit of many a theorist is to make explicit what was implicit in an earlier one; in doing so, he will himself be implying more things than he is actually saying. With both activities he is contributing to the development of the theory of literature. It will be adequate, then, to begin our study of classical literary criticism with a knowledge of some current ideas about literature which were the background to the activity of the early theorists. These ideas are the equivalent to the mythical world-view from which philosophy emerged. Not surprisingly, many literary theorists of ancient Greece (and later too) are also philosophers.