One of the advanced stages of the Hindu system of yoga
practice. According to the Indian teacher Patanjali (ca. 200
B.C.E.), the following stages are prescribed yama and niyama
(ethical restraints and moral observances), asanas (the physical
positions of hatha yoga), pranayama (breathing exercises), pratyahara
(sense withdrawal), dharana (concentration), and dhyana
(meditation), culminating in various degrees of samadhi
Pratyahara involves withdrawing sensory perception from
external objects to concentrate on single-minded contemplation
as a preliminary phase of meditation.
Inengar, B. K. S. Light on Yoga. New York Schocken Books,
Majumdar, Sachindra Kumar. Introduction to Yoga Principles
and Practices. Secaucus, N.J. Citadel Press, 1976.