This dissertation undertakes a comprehensive analysis of the arguments for and against an ontology of momentary temporal parts advanced by a long tradition of Buddhist philosophers in Sanskrit. Drawing on the latest authors in Indian Buddhist schools and using contemporary tools and theories, I defend the Buddhist ontology against the best objections of its Naiyāyika critics, who favor an ontology of enduring substances. The dissertation has six chapters. In the first, I provide an overview of epistemology and ontology in the classical period of Indian civilization. In the second, I discuss how the competing considerations of change and endurance shape the early arguments for and against momentariness. The relationship of properties to property-bearers and of parts to wholes emerges as the central point of contention. In the third chapter, I consider the Buddhist argument that destruction is uncaused. Here the ontological status of absences becomes the crucial issue, and I explain the complex exchanges on this score. In the fourth chapter, I examine the most sophisticated of the Buddhist arguments, an inference based on the thesis that anything that exists has causal efficiency. Causal relations also play a key role in the Buddhist account of the persistence of things as presupposed in everyday discourse. The topic of the unity of a series is continued in the fifth chapter, where I apply Buddhist ideas to the problem of personal identity. Here so-called recognition, our identifying an object as in some sense the same as one previously perceived or cognized, is seen to be the key consideration according to my reconstruction of the classical debate. Especially cross-sensory recognition, seeing now something that one has previously touched, for instance, becomes the central issue. I defend the Buddhist view by giving an account of cross-sensory recognition that countenances no non-momentary entities. In the sixth chapter, I put the Indian dispute into the context of contemporary debates over temporal parts theories. A partial translation of the previously untranslated text, the Kṣaṇabhaṅgasiddhi of Ratnakīrti (an eleventh-century author who may be counted the last of the great Indian Buddhist philosophers), forms an appendix.
