Overview
The most important contribution made by the Nyaya school to modern Hindu thought is its methodology to prove existence of God, based on the Vedas. This methodology is based on a system of logic that, subsequently, has been adopted by the majority of the other Indian schools, orthodox or not. This is comparable to how Western science and philosophy can be said to be largely based on Aristotelian logic.
However, Nyaya differs from Aristotelian logic in that it is more than logic in its own right. Its followers believed that obtaining valid knowledge was the only way to obtain release from suffering. They therefore took great pains to identify valid sources of knowledge and to distinguish these from mere false opinions. Nyaya is thus a form of epistemology in addition to logic.
According to the Nyaya school, there are exactly four sources of knowledge (pramāṇas): perception, inference, comparison, and testimony. Knowledge obtained through each of these can, of course, still be either valid or invalid. As a result, Nyaya scholars again went to great pains to identify, in each case, what it took to make knowledge valid, in the process creating a number of explanatory schemes. In this sense, Nyaya is probably the closest Indian equivalent to contemporary analytic philosophy.
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