The imitation of a handful of accepted literary models lies at the core of the Greco-Roman educational process throughout all of its stages. While at the more advanced levels the relationship to models became more nuanced, the underlying principle remained the imitation of those authors who had achieved greatness. Quintilian explains the rationale as follows:
For there can be no doubt that in art no small portion of our task lies in imitation, since although invention came first and is all-important, it is expedient to imitate whatever has been invented with success. And it is a universal rule of life that we should wish to copy what we approve in others. It is for this reason that boys copy the shapes of letters that they may learn to write, and that musicians take the voices of their teachers, painters the works of their predecessors, and peasants the principles of agriculture which have been proved in practice, as models for their imitation. (Inst. or. 10.2.1-2)
The emphasis on the imitation of models does not stop with a student's education. The primary and secondary stages of education were specifically designed to lay the groundwork for rhetorical training, where a would-be rhetor or writer would learn the subtle art of imitation more fully. Students approached what is essentially the same set of texts at all stages of their education, but in increasingly complex and nuanced ways. The end result was what might be thought of as a mimetic compositional ethos. As rhetors and writers began to practice their craft, the years of training and preparation created, as Ruth Webb puts it, "certain modes of thinking about language, about the classical texts which served as models and about the relation to language in general." These modes of thinking are evident in the widespread imitation of literary models in the literature of the Hellenistic and Roman periods.
Dupertuis, R. R. (2007). Writing and imitation: Greek education in the Greco-Roman world. Forum, 1(1), 3-29.