The basic text of the Yoga philosophical school, the Yoga Sutras of Patanjali (2nd century B.C.), is a systematization of one of these older traditions. Patanjali divides the practice of yoga into eight stages: Yama, or restraint from vice, and Niyama, or observance of purity and virtue, is the moral foundation for practice and removal of the disturbance of uncontrolled desires.
Asana, or posture, and Prana Yama, or breath control, calms the physical body, while Pratyahara, or withdrawal of the senses, detaches the mind from the external world. Internal control of consciousness is accomplished in the final three stages: Dharana, or concentration, Dhyana, or meditation, and Samadhi. It is through such practices that Yogis acquire miraculous powers, which must ultimately be renounced to attain the highest state.
In Samadhi the subject–object distinction and one’s sense of an ‘Individual self’ disappears in a state usually described as one of supreme peace, bliss, and illumination. A common feature of different traditions of yoga is one–pointed concentration on a chosen object, whether a part of the body, the breath, a mantra, a diagram, a deity, or an idea.