The date and identity of the author of the Yoga Sutras is debated, but we know it was comprised thousands of years ago by someone or a group of people collectively referred to as Patanjali. The Yoga Sutras came about as a code of conduct for how to practice yoga during a time when there were a lot of different rituals and rules regarding the attainment of enlightenment. During this time period, practicing these rituals to attain enlightenment was reserved for a select few people who were rich and of the upper castes. (Read on in Tapas and the Disciplines of Yoga.)
Around the same time that the Yoga Sutras were introduced (historically speaking), the Buddha was spreading his new philosophy of Buddhism, which was available to all people no matter what caste they belonged to.
The intent behind the Yoga Sutras was to simplify (hah!) the practices required to attain enlightenment so that it could be made available to all people, regardless of caste or status. A key differentiation point from yoga and the Sankhya philosophy, from which yoga is born, is that yoga practice empowers the individual to take matters into his or her own hands, whereas, Sankhya philosophy instructs an individual to do a set of rigid practices, regardless of whether or not they work for the individual. (Learn more in A Journey Through the 8 Limbs of Yoga.)
In Sankhya philosophy, there is one way to attain enlightenment, and everyone must take the same steps to get there. Yoga philosophy argues that there is a unique path for everyone, and each person must find their own way to enlightenment through practice, reflection and informed decision-making.
To understand the different paths available to the independent yogi, Patanjali outlines three types of yoga. The three types of yoga presented in the Yoga Sutras are Kriya, Ashtanga, and Samyama. There is some debate surrounding the chronology of when these systems were added or explained in the Sutras, because Kriya Yoga and Samyama are part of the overall Ashtanga system, but they also stand on their own as individual systems. Read on in The Founder of Ashtanga Yoga.)
You may have heard of Ashtanga, which in the West, most commonly refers to a particular type of asana (posture) practice. In fact, there is much, much more to Ashtanga then jump-backs and Chatarungas...
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