The Philosophy of the Upanishads c9.s3.t2.1

c9.s3.t2.1

No natural phenomenon bears so ambiguous a character, none appears to be derived so immediately from the most intimate essence of things and so fully to reveal it, as the phenomenon of life, manifested in the activity of all the vital organs (*prânas*), but above all in the process of breathing (*prâna*) which determines the life itself. Hence as early as the Brâhmana period the central significance of *prâna* (breath or life) was discussed together with its superiority to the other *prânas* (vital forces, as the eye, ear, speech, *manas*), and its identity with *Vâyu*, the god of the wind as the vital breath of the universe, was discussed. All these discussions are continued in the Upanishads, especially in the older texts, which yet are unable to apprehend the first principle of the universe otherwise than in its most obvious phenomenal forms; until the *prâna*, whether by a process of subordination or identification, retires more and more behind the âtman, and appears only as an occasional synonym for it.