The Upaniṣads — the philosophical core of the Vedic tradition, revealing the nature of Brahman, the Ātman, knowledge, action and liberation. The ten principal Upaniṣads together with select minor Vaiṣṇava Upaniṣads.
A book told to Śuka — the one who will later relate the Bhāgavatam to the world. It examines the four great sayings and explains why, behind the abstract "that you are," stands not identity, but belonging.