"This work traces the development of mystical thought during the formative periods of the Hindu and Muslim traditions and provides comparisons between the two streams of mysticism. The author's discussion includes the classical Upanishads, the Yogasutras, the Bhagavad-Gita and their commentaries. His study of the Islamic tradition includes the Monastic revolution introduced by Abu Yazid, which the author traces to the influence of Indian thought and the later writings of Ghazali."--Bloomsbury Publishing.