The System of the Vedanta according to Badarayana's Brahma-Sutras and Cankara's Commentary c8.s7.t2.2

c8.s7.t2.2

In deep, *i.e.* dreamless sleep, the soul becomes temporarily one with Brahman. In course of time this doctrine, which, in our opinion, only expressed the extinction of conscious in unconscious life, that is perceived in sleep by simple observation, assumed an essentially different meaning. According as the soul came to be regarded as an essentially intellectual potency a separation of it from the *Mukhya Prâna* as principle of the unconscious life and a closer connection with the organs of conscious life, *viz.* *Manas* and *Indriyas*, became necessary. In deep sleep this connection is temporarily dissolved in such a way that *Manas* and *Indriyas* enter into the *Prâna*, and the soul on the other hand is submerged in the Brahman who sojourns in the ether of the heart. Çañkara's statements on this point are concerned with special questions and rest on assumptions which are nowhere clearly developed; we must therefore by putting things together attempt to lay down what these were.