The Patanjali's Yoga Sutra outlines the eight limbs of yoga which are yamas (universal ethics), niyamas (self purification), asana (postures), pranayama (breathing), pratyahara (sense withdrawal), dharana (concentration), dhyana (meditation), and samadhi (enlightenment/liberation). It discusses the practice of yoga and how it can help eliminate the causes of suffering. The goal of yoga according to Patanjali is kaivalya, i.e., isolation of the mind from all its modifications and finding union with the eternal unchanging reality or purusha.