Lived in the second century. Indian thinker whose influence pervaded the second 500 years of the religious and philosophical history of Buddhism.

In his treatise Mulamadhyamakakarika (Fundamentals of the Middle Way), Nagarjuna used an analysis of the philosophical teachings of his time to provide models of a dialectical method applicable to the theory of knowledge. Refusing to define his own philosophical position, Nagarjuna proposed methods of negative criticism that could be applied to any theory. These methods he called sunyavada, or “the teaching about the emptiness (of all points of view)”; they could be used to demonstrate the contradictoriness of the categories and concepts of any philosophical system. According to Nagarjuna, any statement about the nature of reality and about the existence of objects given in experience, or of the bearer of this experience, is unprovable.

The Madhyamika school, which Nagarjuna founded, was the earliest in the history of philosophy to single out methodology as a separate study, inasmuch as the school’s field of investigation was not reality itself, but the various theories of reality.

Nagarjuna’s dialectical methodology was a powerful incentive to philosophical and scientific thought in India. In particular, in mathematics, the concept of zero as the difference in points of view from the absolute point of view was first defined under the influence of his methodology. Nagarjuna’s methodology underwent further development in the Prajnyaparamita Sutras (Perfection of Wisdom Verses), which contains the teaching about emptiness as a place absolutely free of consciousness. His relativist ethics was later thoroughly elaborated in Tantrism and Zen Buddhism. Finally, Nagarjuna’s dialectical method was taken out of its specifically Buddhist context and used as the basis for the systematic philosophy of the advaita vedanta created by Shankara.