We know very little of our bodies and minds, of the fine process within, that keep the lamp of life and thought shining bright. The reason for this is that, only when the mind becomes very subtle, can it enter into the depth of our being and watch the subtle movements of the body. To get the subtle perception, we have to begin with the grosser perceptions. We have to get hold of that which is setting the whole engine in motion; that is the prana, the most obvious manifestation is the breath. Then, along with the breath, we shall slowly enter the body and come across the subtle forces, the nerve currents, that are moving all through the body. As soon as we perceive and feel them, we shall begin to get control over them and over the body. The mind also is set in motion by these different nerve currents; so at last we shall reach the state of perfect control over the body and mind, making both our servants. Knowledge is power; we have to get this power, so we must begin at the beginning – the Pranayama or the restraining of the Prana.
- Swami Vivekananda
(Excerpts from The Four Yogas of Swami Vivekananda, condensed and retold by Swami Tapasyananda)