Health depends upon the balance between activity and repose in the five senses: sight, smell, hearing, taste, and touch; and every sense, in the normal condition of health, must be able to express itself and to respond. The senses need more time for repose than for activity. Therefore the mystics go into seclusion in order to give a chance of repose to the senses, which are different in every man. Everyone passes every moment of his waking state in activity of the senses, partly by intention, partly involuntarily. For instance, the eyes look at things intentionally perhaps a hundred times a day, but nine hundred times they look at things without intention. This shows a waste of energy in an average man's life.