奥义书——吠陀传统的哲学核心，阐明梵、真我、知识、行动与解脱的本质。十部主要奥义书，另加精选的毗湿奴派小奥义书。
Twelve lines on the syllable Oṃ and the four states: waking, dreaming, deep sleep, and the fourth — that which neither sleeps nor wakes. The most compressed book of the collection: whole treatises are written on it, yet it can be read in a minute.