Sri Aurobindo translates Aitareya Upanishad, Chapter 1, Section 3 (part 2): “The Spirit thought, ‘Without Me how should all this be? and He thought, ‘By what way shall I enter in? He thought also, ‘If utterance is by Speech, if breathing is by the Breath, if sight is by the Eye, if hearing is by the Ear, if thought is by the Mind, if the lower workings are by apana, if emission is by the organ, who then am I? It was this bound that He cleft, it was by this door that He entered in. ‘Tis this that is called the gate of the cleaving; this is the door of His coming and here is the place of His delight. He hath three mansions in His city, three dreams wherein He dwelleth, and of each in turn He saith, ‘Lo, this is my habitation’ and ‘This is my habitation’ and ‘This is my habitation.’ Now when He was born, He thought and spoke only of Nature and her creations; in this world of matter of what else should He speak or reason? Thereafter He beheld that Being who is the Brahman and the last Essence. He said, ‘Yea, this is He; verily, I have beheld Him.’ There is He Idandra; for Idandra is the true name of Him. But though He is Idandra, they call Him Indra because of the veil of the Unrevelation; for the gods love the veil of the Unrevelation, yea, verily, the gods love the Unrevelation.”
The Spirit has built a house, with all its machinery functional and ready to be put into operation. But who is to experience and enjoy the operation of that machinery in that dwelling? The three mansions referenced here have multiple different potential explanations, but within the context of the Upanishad itself, it is likely to refer to Matter, Life and Mind. The three dreams appear to be the 3 states of awareness, waking, dream and dreamless sleep, which in one sense are all “dreams”. Sometimes we experience the dream state as if it were our reality, and the waking state as if it is a dream. In an ultimate sense, these are all states of “dream”. What is missing in all of this is the witness, the experiencer of all experience.
The Spirit is not separate from this creation, so the Spirit, which is all-consciousness, must also have a seat in the house. The Spirit inhabits this house and uses all the machinery of body, life and mind for its experience. The conscious-awareness in the being is call the Jivatman, and it enters and departs the structure through the Brahmarandhra, the soft-spot in the top of the head. As the Taittiriya Upanishad states “where the hair at its end whirleth round like an eddy, there it divideth the skull and pusheth through it.”
The human individual is immersed in the experience of Nature and therefore focuses his attention there. It is possible however to turn the attention inward, to seek the being that “enjoys” Nature, and thereby to behold the Brahman, beyond and outside all the dream states. The Upanishad names the perceiver of the Brahman as Idandra. Idandra means “he who perceives”. We see here a connection made to Indra, the universal power of the divine mind. It should be noted that in the Kena Upanishad Indra is the one god who perceives the Brahman. The universal powers, as noted in the Kena Upanishad, all take upon themselves the power and generally fail to recognise that it is the Brahman, not themselves, who is the source of their powers. Thus, the statement that they “love the Unrevelation.”
Sri Aurobindo, The Upanishads, Aitareya Upanishad, pp.285-294