Up. (I, 4) applies the terms apara and para vidya.  But a formal recognition of the essential difference of Brahman being viewed, on the one hand, as possessing distinctive attributes, and, on the other hand, as devoid of all such attributes is not to be met with anywhere.  Brahman is indeed sometimes described as sagu/n/a and sometimes as nirgu/n/a (to use later terms); but it is nowhere said that thereon rests a distinction of two different kinds of knowledge leading to altogether different results.  The knowledge of Brahman is one, under whatever aspects it is viewed; hence the circumstance (already exemplified above) that in the same vidyas it is spoken of as sagu/n/a as well as nirgu/n/a.  When the mind of the writer dwells on the fact that Brahman is that from which all this world originates, and in which it rests, he naturally applies to it distinctive attributes pointing at its relation to the world; Brahman, then, is called the Self and life of all, the inward ruler, the omniscient Lord, and so on.  When, on the other hand, the author follows out the idea that Brahman may be viewed in itself as the mysterious reality of which the whole expanse of the world is only an outward manifestation, then it strikes him that no idea or term derived from sensible experience can rightly be applied to it, that nothing more may be predicated of it but that it is neither this nor that.  But these are only two aspects of the cognition of one and the same entity.

Closely connected with the question as to the double nature of the Brahman of the Upanishads is the question as to their teaching Maya.—­From Colebrooke downwards the majority of European writers have inclined towards the opinion that the doctrine of Maya, i.e. of the unreal illusory character of the sensible world, does not constitute a feature of the primitive philosophy of the Upanishads, but was introduced into the system at some later period, whether by Badaraya/n/a or Sa@nkara or somebody else.  The opposite view, viz. that the doctrine of Maya forms an integral element of the teaching of the Upanishads, is implied in them everywhere, and enunciated more or less distinctly in more than one place, has in recent times been advocated with much force by Mr. Gough in the ninth chapter of his Philosophy of the Upanishads.

In his Materiaux, &c.  M. Paul Regnaud remarks that ’the doctrine of Maya, although implied in the teaching of the Upanishads, could hardly become clear and explicit before the system had reached a stage of development necessitating a choice between admitting two co-existent eternal principles (which became the basis of the Sa@nkhya philosophy), and accepting the predominance of the intellectual principle, which in the end necessarily led to the negation of the opposite principle.’—­To the two alternatives here referred to as possible we, however, have to add a third one, viz. that form of the Vedanta of which the theory of the Bhagavatas or Ramanujas