Patańjali, is the compiler of the Yoga Sutra, a major work containing aphorisms on the practical and philosophical wisdom regarding practice of Raja yoga. ("Yoga" in traditional Hinduism involves inner contemplation, a rigorous system meditation practice, ethics, metaphysics, and devotion to the one common soul, God, or Brahman/Atman.)
Virtually nothing is known about the life of Patanjali, and some scholars believe he is entirely mythical. Various references suggest he lived between 200 BC and 400 AD. Ancient texts often refer to Patanjali as an incarnation of the serpent god Ananta, and he is sometimes depicted as half human and half serpent.
Patanjali is the reputed author of the Yoga Sutra, as well as commentary on Panini's Sanskrit grammar (aShTAdhyAyI) which is called 'mahAbhAShya'. There are also many ayurvedic texts attributed to him. Nearly all scholars believe these texts were actually written by different people in different eras.
The Yoga Sutra probably dates from around AD 200. Patanjali has often been called the founder of Yoga because of this work, although in reality is more a major figure. The Yoga Sutra is a treatise on Raja Yoga, built on Samkhya and the Hindu scripture of the Bhagavad Gita. Yoga is also found in the Puranas, Vedas and Upanishads. Still, this work is certainly a major work among the great Hindu scriptures and certainly is the basis of Raja Yoga. Patanjali's Yoga is part of the six schools of Hindu Philosophy. They give us the earliest reference to the popular term Ashtanga Yoga which translates literally as the eight limbs of yoga. They are yama, niyama, asana, pranayama, pratyahara, dharana, dhyana and samadhi.
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