The Upanishads declare a number of truths that, on their surface, appear to be somewhat contradictory, but viewed from another standpoint, make absolute sense. On the one hand, the Absolute Brahman is viewed as unknowable, beyond anything that the limited mind and senses of a human being can possibly comprehend, and the solution to gaining some form of knowledge is usually a recommendation to abandon the life in the world, do away with all forms of desire,and fix the consciousness on the silent, infinite, Absolute. On the other hand, the Upanishads declare “all this is the Brahman” and thus, imply that the world we live in, the experiences we have, the perceptions we receive, the thoughts we think, are all Brahman. Eventually the sages concluded with the phrase “So ‘ham” and “Aham Brahm’ Asmi”, one generally translated as “He am I” and the other as “I am Brahman”. These conclusions are the inevitable result of a recognition that the entire universal creation is one with the Transcendent Brahman, and thus, at the level of particularity, I also am That.
Sri Aurobindo observes: “But this will not necessarily mean the immersion into an all-oblivious Being eternally absorbed in His own inactive self-existence. For the mind, sense, life going beyond their individual formations find that they are only one centre of the sole Mind, Life, Form of things and therefore they find Brahman in that also and not only in an individual transcendence; they bring down the vision of the superconscient into that also and not only into their own individual workings. The mind of the individual escapes from its limits and becomes the one universal mind, his life the one universal life, his bodily sense the sense of the whole universe and even more as his own indivisible Brahman-body. He perceives the universe in himself and he perceives also his self in all existences and knows it to be the one, the omnipresent, the single-multiple all-inhabiting Lord and Reality. Without this realisation he has not fulfilled the condition of immortality. Therefore it is said that what the sages seek is to distinguish and see the Brahman in all existences; by that discovery, realisation and possession of Him everywhere and in all they attain to their immortal existence.”
Sri Aurobindo, The Upanishads, Kena Upanishad and analysis, pg. 186
Sri Aurobindo Studies 