The System of the Vedanta according to Badarayana's Brahma-Sutras and Cankara's Commentary c6.s3.t7.3

c6.s3.t7.3

(Bṛih. 3, 4:) “Then asked him Ushasta, the descendant of “Cakra. ‘Yâjñavalkya,’ said he, ‘the immanent, non-transcen- “dent Brahman, which as soul is innermost of all, that shalt “thou declare to me.’—‘It is thy soul, which is innermost of “all.’—‘Which, o Yâjñavalkya, is innermost of all?’—‘That “which inbreathes by inbreath that is thy soul, the inner“most of all, that which outbreathes by outbreath that is “thy soul, the innermost of all, that which interbreathes by “interbreath that is thy soul, the innermost of all, that which “upbreathes by upbreath that is thy soul, the innermost of “all,—this is thy soul, which is innermost of all.’—Then said “Ushasta, the descendant of Cakra: ‘It is only indicated by “this, as when one says: that is a cow, that is a horse; but “the immanent, non-transcendent Brahman, the soul, which is “innermost of all, that shalt thou declare to me!’—‘It is thy “soul which is innermost of all.’—‘Which, o Yâjñavalkya, is “innermost of all?’—‘Thou canst not see the seer of seeing, “nor canst thou hear the hearer of hearing, nor canst thou “understand the understander of understanding, nor canst “thou know the knower of knowing. He is thy soul, which “is innermost of all.—What is different from him is afflicted.’ “—Then Ushasta, the descendant of Cakra, was silent.”