When Horace turned from Sermones and Epodes to the composition of lyrics, the task that he set himself was a complex one. Like Virgil, Horace accepted wholeheartedly the poetic ideals of careful craftsmanship and sophistication advocated by Callimachus and the Alexandrians and first represented in Rome by Catullus, Calvus and Cinna. Nevertheless, the Alexandrian and neoteric programs were not enough for Horace and Virgil: both were deeply affected by the times in which they lived and were therefore determined to deal with contemporary affairs in their poetry. This determination eventually led Virgil to the "impossible" task of adapting the classical Greek form of epic to his own Roman world without falling into the difficulties inherent in the genre of Roman historical epic. Horace, on the other hand, had no ambitions to write on the grand scale. He chose instead a genre which would allow him the freedom to alternate between slight and elegant poems (ludi) and those of a more serious nature, whether political or philosophical. The Alexandrian forms could not offer him this freedom; nor could the exigui elegi of Gallus and his followers. Thus, he too turned to a classical form: lyric. This genre filled his needs admirably, for it was traditionally capable of enormous diversity: hymn, subjective love poetry, political, philosophical, and convivial poems all fell within its province. Furthermore, its metrical variety offered him ample opportunity to display his technical virtuosity.
McDermott, Emily A., "Horatius Callidus" (1977). American Journal of Philology. Vol. 98, pp. 363-380. http://scholarworks.umb.edu/classics_faculty_pubs/15
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