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 on "the unmanifest" and on Nṛsiṃha: how the world unfolds from the invisible, and why the Lion who appeared is that very unmanifest, become visible. It ends with a ban on teaching it to one not devoted to Viṣṇu.