This volume provides a detailed resume of current knowledge about the classical Indian Philosophical systems of Nyaya and Vaisesika in their earlier stages, i.e. covering the literature from their inception in the sutras of Gautama and Kanada before the time of Gangesa (about A.D. 1350). The summaries are arranged in relative chronolo-gical order to assist the reader in tracing the development of the syncretic school,s thought. Scholars around the world-India, Japan, American-have collaborated in the undertaking. The summaries in the volume serve as a tool for introducing Indian thought into their courses on problems of Philosophy, history of thought, etc. and guide the students for further study.