[1] It is associated with the Kaushitaki shakha, but a Sāmānya Upanishad, meaning that it is "common" to all schools of Vedanta.
[1][3] Paul Deussen suggests that these different chapter numbers may reflect that Upanishadic layer of Vedic literature were created and incorporated as spiritual knowledge in the pre-existing Aranyaka-layer of Vedic texts, and when this was being done in distant parts of India, the sequencing information was not implemented uniformly.
[1] The Kausitaki Upanishad is a prose text, divided into four chapters, containing 6,[13] 15, 9 and 20 verses respectively.
[3] Divisions Sama vedic Yajur vedic Atharva vedic Vaishnava puranas Shaiva puranas Shakta puranas In the first chapter of the Kausitaki Upanishad, rebirth and transmigration of Atman (Self) is asserted as existent, and that one's life is affected by karma, and then it asks whether there is liberation and freedom from the cycles of birth and rebirth.
Edward Cowell translates the above verses that declare the "Oneness in Atman and Brahman" principle as follows, (The Self answers, when asked by Brahma, "Who art thou?")
In the second chapter of the Kausitaki Upanishad, each life and all lives is declared as Brahman (Universal Self, Eternal Being).
He doesn't need to pray, states Kausitaki Upanishad, the one who realizes and understands his true nature as identical with the universe, the Brahman.
Then it posits that freedom and liberation comes not from sense-objects, not from sense-organs, not from subjective psychological powers of mind, but that it comes from "knowledge and action" alone.
The one who knows Self, and acts harmoniously with the Self, solemnly exists as the highest God which is that Self (Atman) itself.
The chapter presents the metaphysical definition of a human being as Consciousness, Atman, Self.
Edward Cowell translates these last verses as, "Prāṇa is prajñā, it is joy, it is eternally young, it is immortal.
[24] This last chapter of Kausitaki Upanishad states that Brahman and Self are one, there is ultimate unity in the Self, which is the creative, pervasive, supreme and universal in each living being.
The most cited English translations are those by Eduard Cowell,[3] Paul Deussen, Robert Hume and Max Müller.