Part I outlines the historical background out of which Buddhism arose and emphasizes the teachings of early Buddhism. By comparing the earliest Buddhist literature in both the Pali Nikayas and the Chinese Agamas, the author has established the common base of earliest Buddhism most free of sectarian rivalry. Topics such as epistemology, causality, existence, karma, morality, ethics, and nirvana are discussed in detail.

Part II examines developments in the history of Buddhist thought and the emergence of the various schools of Buddhism. The development of Abhidharma is studied through analysis of the various doctrines of the scholastics that comprise Abhidharma literature, as is early Mahayana through the Mahayana sutras. Two chapters examine Madhyamika Transcendentalism and Yogacara Idealism. The Buddha's attitude toward metaphysics and the relationship between early Buddhism and Zen are covered in two appendices.