 The earliest clear references to meditation in Hindu literature are in the middle Upanishads and the Mahabharata (including the Bhagavad Gita).According to Gavin Flood, the earlier Brihadaranyaka Upanishad is describing meditation when it states that "having become calm and concentrated, one perceives the self ("ātman") within oneself".One of the most influential texts of classical Hindu Yoga is Patañjali's Yoga sutras (c. 400 CE), a text associated with Yoga and Samkhya, which outlines eight limbs leading to kaivalya ("aloneness").