The conception of a world-soul related to the universe as the soul of man to his body is found for the first time in R.V.X. 121. I, where he is said to have sprung forth as the firstborn of creation from the primeval waters. This being has twice been referred to in the S'vetâs'vatara, in III. 4 and IV. 12. It is indeed very strange that this being is not referred to in any of the earlier Upani@sads. In the two passages in which he has been spoken of, his mythical character is apparent. He is regarded as one of the earlier products in the process of cosmic creation, but his importance from the point of view of the development of the theory of Brahman or Âtman is almost nothing. The fact that neither the Puru@sa, nor the Vis'vakarma, nor the Hira@nyagarbha played an important part in the earlier development of the Upani@sads leads me to think that the Upani@sad doctrines were not directly developed from the monotheistic tendencies of the later @Rg-Veda speculations. The passages in S'vetâs'vatara clearly show how from the supreme eminence that he had in R.V.X. 121, Hira@nyagarbha had been brought to the level of one of the created beings. Deussen in explaining the philosophical significance of the Hira@nyagarbha doctrine of the Upani@sads says that the "entire objective universe is possible only in so far as it is sustained by a knowing subject. This subject as a sustainer of the objective universe is manifested in all individual objects but is by no means identical with them. For the individual objects pass away but the objective universe continues to exist without them; there exists therefore the eternal knowing subject also (_hira@nyagarbha_) by whom it is sustained. Space and time are derived from this subject. It is itself accordingly not in space and does not belong to time, and therefore from an empirical point of view it is in general non-existent; it has no empirical but only a metaphysical reality [Footnote ref 1]." This however seems to me to be wholly irrelevant, since the Hira@nyagarbha doctrine cannot be supposed to have any philosophical importance in the Upani@sads. The Theory of Causation. There was practically no systematic theory of causation in the Upani@sads. S'a@nkara, the later exponent of Vedânta philosophy, always tried to show that the Upani@sads looked upon the cause ___________________________________________________________________ [Footnote 1: Deussen's _Philosophy of the Upanishads_, p. 201.] 53