This dissertation looks at debates over the Tamil literary tradition in treatises and commentaries on poetics composed in South India between the eighth and the seventeenth centuries. Central to these discussions of what constitutes the literary was the relationship of new literary developments to the language and conventions of an ancient poetic system established in the earliest stratum of Tamil literature, known as "Sangam literature" or "literature of the assembly." The chapters that follow look at these competing attitudes towards the classical tradition, beginning with the debates over defining the Tamil tradition found in Pera ciriyar's thirteenth-century commentary on the section of poetics discussed by the ancient grammar Tolkappiyam , and the Virutti commentary on the metrical treatise Yapparun˙kalam, dated between the eleventh and twelfth centuries. The different interpretations of the Tamil past adopted by these commentaries reveal the capacity of the Sangam tradition to serve both as the foundation of an authoritative canon worthy of preservation as well as fertile material for experiments with new theories of literature and language, including those derived from Sanskrit. If the first two chapters explore the central role played by the Sangam conventions in Tamil literary theory, albeit mobilized for different interpretive projects, the next two chapters focus on the competing poetic system of the pa˙t&dotbelow;t&dotbelow;iyals , which theorize the capacity of Tamil language and literature to praise a royal patron, and explore the implications of this new understanding of the function of literary language. Finally, the dissertation ends with a seventeenth-century text, the Ilakkan&dotbelow;a Vil&dotbelow;akkam , which attempts an integrated theory of Tamil literature, in which the most influential "new" developments in Tamil aesthetics, including the praise poetics of the pa˙t&dotbelow;t&dotbelow;iyals, are rendered compatible with the Sangam tradition. By providing a comparative look at approaches to interpreting the Tamil literary tradition, this dissertation hopes to bring attention to the important role played by comparative literary theory in our approach both to the study of South Asian literature and to the study of world literature more generally.