William Walker Atkinson,
The Hindu-Yogi Science of Breath
“ EXERCISE.—Place your body in a relaxed, reclining position. Breathe rhythmically, and meditate upon the real Self, thinking of yourself as an entity independent of the body, although inhabiting it and being able to leave it at will. Think of yourself, not as the body, but as a spirit, and of your body as but a shell, useful and comfortable, but not a part of the real You. ”
