The Taittiriya Upanishad is a principal Upanishad of Hindu philosophy, part of the Yajur Veda. It is divided into three sections (Vallis) that explore the nature of reality, the self (Atman), and the ultimate purpose of life. It introduces the concept of five sheaths (Panchakosha) that cover the true self, and emphasizes that Brahman, the ultimate reality, is bliss (Ananda). The text highlights the importance of knowledge, ethical living, and self-inquiry for achieving self-realization and liberation.

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