Vitality

Vitality means life-force—wherever there is life, in plant or animal or man, there is life-force—without the vital there can be no life in matter and no living action. The vital is a necessary force and nothing can be done or created in the bodily existence, if the vital is not there as an instrument. Even sadhana needs the vital force.

But if the vital is unregenerated and enslaved to desire, passion and ego, then it is as harmful as it can otherwise be helpful. Even in ordinary life the vital has to be controlled by the mind and mental will, otherwise it brings disorder or disaster. When people speak of a vital man, they mean one under the domination of vital force not controlled by the mind or the spirit. The vital can be a good instrument, but it is a bad master.

The vital has not to be killed or destroyed, but purified and transformed by the psychic and spiritual control.

Ref : Letters on Yoga Vol. I