Patanjali
Indian author and compiler (uncertain date, probably between the second century BC and the fourth century AD) to whom tradition attributes the Yoga Sutras, the founding text of classical yoga as a rigorous philosophical system, though modern scholarship doubts he was a single historical figure and suggests instead a compilation of several sources over time under a venerated name. The text, composed of some 196 extremely brief aphorisms arranged in four books, systematises for the first time the practices and philosophy of yoga within the framework of Samkhya philosophy, with which it shares the fundamental dualism between purusha (pure consciousness, the unchanging witness) and prakriti (matter, including the mind and its activities). The famous definition that opens the work, 'yogash chitta-vritti-nirodhah' — 'yoga is the cessation of the fluctuations of the mind' — establishes the goal of the entire practice: to halt the incessant activity of thought so that consciousness may rest in its own nature, free from any mistaken identification with mental contents. To achieve this, Patanjali sets out the eight-limbed system (ashtanga yoga): the ethical principles of restraint (yama) and observance (niyama), physical posture (asana), breath control (pranayama), withdrawal of the senses (pratyahara), concentration (dharana), sustained meditation (dhyana) and, finally, total absorption (samadhi), in which all distinction between subject and object disappears. This framework, originally oriented toward spiritual liberation (kaivalya) rather than physical well-being, is today the philosophical foundation of the vast majority of yoga traditions practised worldwide, though often reduced solely to their postural aspects.