The Positive Sciences of the Ancient Hindus c10.42

c10.42

*The Nyáya Doctrine of Inference.*—The Nyáya easily demolishes the Buddhist contention about identity of essence. The Nyáya writers, being realists, do not impugn the reality of the genus (जाति) like the nominalists or the nominalistic conceptualists; but they point out that the inseparableness (or non-disjunction) in such cases can only be established by the experience of unbroken uniformity (अव्यभिचारित्व, *i.e.* by अन्वयव्यतिरेकौ, दर्शनादर्शने). Uniform agreement in presence with uniform agreement in absence—not the mysterious identity of essence irresistibly perceived in any individual case or cases—is the only basis for constituting genera and species in natural classification. Indeed, some of the later Nyáya writers point out that individuals do not always possess in nature all the characters that go to form the definition of the class to which they are referred.