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.
Nine lines — the shortest book in the collection: a list of classes of mendicants, from those living on alms to those who have left even the staff. Its measure is not clothing, but purity of mind.