Nyāya Sūtra

The root text of the Nyāya school: five books of terse aphorisms that only make sense with commentary, above all that of Vātsyāyana. It opens by listing sixteen topics whose correct knowledge leads to the highest good, beginning with the means of knowledge (pramāṇa): perception, inference, comparison and testimony. It defines each, sets out the five-membered argument (thesis, reason, example, application, conclusion), and distinguishes honest discussion from disputation aimed at victory and from purely destructive wrangling. Long sections analyse fallacious reasons, quibbles, futile rejoinders and the points at which a debater is defeated. The text also defends the reality of wholes and of the external world and argues for an enduring self against Buddhist opponents, and it treats doubt, error and the way knowledge brings release from suffering. Later Navya-Nyāya built a highly technical logic on these foundations.

It is the founding document of Indian logic and epistemology, and its treatment of debate and fallacy is a manual for arguing well with no exact Greek counterpart.