a constraint on the writer and a "latent demand for innovation." The writer "is expected to manipulate the existing conventions and to carry them (at least) one step further…. From the writer's perspective, the generic convention is a model to follow but also a challenge to overcome." Fishelov explains that writers choose or are compelled to manipulate prevailing conventions for a variety of aesthetic and thematic reasons. History of genre theory Genre theory or genre studies got underway with the Ancient Greeks, who felt that particular types of people would produce only certain types of poetry. or oratory. Regarding literary theory, the Greeks also believed that certain metrical forms were suited only to certain genres. Aristotle said, We have, then, a natural instinct for representation and for tune and rhythm—and starting with these instincts men very gradually developed them until they produced poetry out of their improvisations. Poetry then split into two kinds according to the poet's nature. For the more serious poets represented the noble deeds of noble men, while those of a less exalted nature represented the actions of inferior men, at first writing satire just as the others wrote hymns and eulogies. This is all based on Plato's mimetic principle. Exalted people will, in imitation of exaltation, write about exalted people doing exalted things, and vice versa with the "lower" types (Farrell, 383). Genre was not a black-and-white issue even for Aristotle, who recognized that though the "Iliad" is an epic it can be considered a tragedy as well, both because of its tone as well as the nobility of its characters. However, most of the Greek critics were less acutely aware—if aware at all—of the inconsistencies in this system. For these critics, there was no room for ambiguity in their literary taxonomy because these categories were thought to have innate qualities that could not be disregarded. The Romans carried on the Greek tradition of literary criticism. The Roman critics were quite happy to continue on in the assumption that there were essential differences between the types of poetry and drama. There is much evidence in their works that Roman writers themselves saw through these ideas and understood genres and how they function on a more advanced level. However, it was the critics who left their mark on Roman literary criticism, and they were not innovators. Regarding rhetorical genres, although a general classification of various kinds of