The aim of this thesis is to examine the meanings and functions of paradox in the late Renaissance. My understanding of Renaissance paradox, in contrast to that of most critics and historians, rests entirely on contemporary definitions of the term, rather than on its present-day meaning. Paradoxes as they are envisaged in this study begin to appear in the wake of the humanist rediscovery and dissemination of Cicero's Paradoxa Stoicorum. In this work, paradoxes are characterized as 'admirabilia contraque opinionem omnium', a definition that draws attention to two important traits of paradox, repeatedly invoked in the Renaissance: its association with wonder, and its opposition to common opinion. This thesis examines the history of classical paradox as it was revived, expanded beyond the narrow confines of Stoic ethics, and adapted to new purposes so successfully that it became a recognisable genre of polemical writing, with hundreds of works in Latin and the vernacular being described as paradoxes. Previous studies of Renaissance paradox have centred almost exclusively on its literary and vernacular manifestations, and on the paradoxical encomium in particular. My own work charts the rise to prominence and the ensuing transformations of paradox in a range of disciplines: rhetoric and ethics, theology, law, medicine, and natural philosophy. I compare the different associations that paradoxes acquire in all these areas, and the argumentative strategies that they deploy. My analysis of specific examples of paradox is informed by the methods of both literary analysis and intellectual history. Paradoxes, I argue, offered their authors the possibility of departing from established norms and of voicing novel views in a period of intellectual unrest. In their challenge to received and common opinion, they paved the way for more radical ideas in the following century, and they have much to tell us about dissident ways of thinking in the late Renaissance.