AITAREYA UPANISHAD · 3.1.1

कोऽयमात्मेति वयमुपास्महे कतरः स आत्मा । येन वा पश्यति येन वा शृणोति येन वा गन्धानाजिघ्रति येन वा वाचं व्याकरोति येन वा स्वादु चास्वादु च विजानाति ॥ १ ॥

ko’yamātmeti vayamupāsmahe kataraḥ sa ātmā । yena vā paśyati yena vā śṛṇoti yena vā gandhānājighrati yena vā vācaṃ vyākaroti yena vā svādu cāsvādu ca vijānāti ॥ 1 ॥

Who is this Spirit that we may adore Him? and which of all these is the Spirit? by whom one seeth or by whom one heareth or by whom one smelleth all kinds of perfume or by whom one uttereth clearness of speech or by whom one knoweth the sweet and bitter.

Sri Aurobindo · CWSA 18, p. 204