According to 1-ching's report from India (A.D. 691), Mahayana Bud- dhism was divided into two schools, the Madhyamika and the Yogacara. The Madhyamaka (middle) philosophy, founded on Nagarjuna's (A.D. second to third century) philosophy of absolute negation (sunyatii), is really a remarkable and probably one of the greatest achievements in the history of Buddhism. It is my contention, however, that it was brought to completion by the Yogacara, especially through the works of Asanga and Vasubandhu (A.D. fifth century). They complemented the sunyata philosophy with various positive theories such as the theory of consciousness-only, the three- nature theory, the theory of Buddha's body, and so on. The Yogacara theories are said to be ''positive'' because by accepting the negative idea of sunyata as a whole, the Yogacara established the positive affirmative aspect of sunyata (abhavasya bhavah). During the later centuries, Indian Buddhism (as well as Tibetan Buddhism) focused its attention on only the Madhyamika school as the main stream of Buddhism while it overlooked the Yogacara as an independent school. In spite of that, ideas and terminologies created by the Yogacara school continued to influence the development of Buddhism in India (also in Tibet) for a long time, and it can be said further that, without the effort and achievement of the Yogacara, which complemented the Madhyamika, Mahayana Buddhism would not have reached its present perfection. (Nagao, 1991, p. xi)
The Madhyamika thought of sunyata was extended by the Yogacara by their system of the Three-nature theory that depended upon a logic of convertibility. (ibid, p. 1)
