The faculty of seeing through life can be developed by observation, which is called study; and the focusing of the mind upon the object of study is called concentration. As by making a habit of lifting one thing, a person can learn to lift several different weighty things, so by observing one object of study a man becomes capable of observing any object in the same way. Keenness of observation is a phenomenon in itself. In the first place, the sight penetrates, so to speak, the object one sees; and the next thing is that as the light of the sun has the power to open the buds, so the power of keen observation commands the objects observed to unfold themselves and to reveal their secrets.