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NYAYA THTORY OF KNOWLEDGE
But for the Naiyāyikas, particularity also is a subsistent fact and the relation of conjunction (samyoga) has existence as an attribute of the substances related by it.
All realities, we have said, are brought under the seven categories. But all of them cannot ordinarily be objects of perception. Hence with regard to the different objects included under each of the categories we have to distinguishi between those that are perceived and those that are imperceptible.
2. Perception of substances or things (dravya)
A substance is defined as the constitutive cause of things or as the substratum of qualities. There are nine kinds of substances. These are : earth, water, light, air, ākāśa, time, space, soul and mind. Of these, the first four stand for both the atoms of earth, water, light and air, and the compounds formed by these atoms. The atoms of earth, etc., cannot be perceived. A compound of two atoms, called dvyanuka or the dyad, is also imperceptible, because, like an atom, it has no dimension and manifest quality (mahattva and udbhūtatva) Mind (manas) as another atomic substance is not an object of ordinary sense perception So also ākāśa, time and space are, according to the NvāyaVaišeşikas, imperceptible substances.: A kāśa is an allpervading medium which is inferred from the phenomena of sound. Space and time are conceived as two receptacles of unlimited dimension holding all things and events witbin them. These two are the most fundamental conditions for the existence of finite objects and are therefore called the origin of all that is originated (janyānāṁ janakah). Each
1 Samaväyıkáranain rava'), saņābray.) v&, TB, P 20, 3 BP , 3 3 TB, and TM Ch. 1.