Pratyahara, the fifth limb in Ashtanga yoga, means to consciously withdraw energy from the senses and the world. In yoga one way to begin to understand it is to practice the corpse pose. By remaining motionless and letting go of all stress and tension, you begin to achieve a wonderful state of stillness while the world goes on around you. You achieve a state of nonreaction—like a leaf floating on the water, you are in the world, but not of it.