By combining deep breathing with gentle smiling, both acts being done quite slowly, and by keeping the mind solely attentive to the body's condition, a relaxed half-drowsy state will develop. No other thoughts should be allowed to enter; the whole of his being should lie completely reposed in the rhythmic breathing and happily hypnotized by the lazy smile. Everything should be light and effortless. This is the Yoga of the Liberating Smile.
-- Notebooks Category 23: Advanced Contemplation > Chapter 6: Advanced Meditation > # 51