DISSERTATION ABSTRACT My research is designed to plumb a question crucial to our understanding of both Dante and Petrarch: do they write for heaven or for earth? Does their poetry operate, as holds the present scholarly consensus, within the confines of Ciceronian rhetorical norms, whether aimed at practical reform within the sphere of politics, or else, failing that, representing a withdrawal into wishful thinking or pessimistic introspection? How does their seeming interest in the renewal of the Roman Empire correlate with the otherwordly commitments of their Christian faith? It is my contention that the two elements are complementary rather than competitive: that both poets are able to maintain a vital interest and engagement with the world while at the same time recognizing the inevitable tragedy of human history; and that they do this by adopting the rhetorical stance of Jeremiah. If the moral suasion of Classical Humanist rhetoric must ultimately fail to save the world from its vices, to avoid despair requires a vision of the world redeemed.