On a careful analysis we find that man’s happiness is entirely a subjective phenomenon, for there seems to be a distinct and clear relationship between the state of his mind and the joy or sorrow that is experienced by him. When the mind is agitated, sorrow is experienced and when it is tranquil, there is joy. Happiness, therefore, is measured by the tranquility of one’s mind.
Man, the roof and crown of creation, has the unique capacity of quieting his mind without helplessly depending upon the objects around him. But this capacity now lies dormant in him and he, unaware of it, foolishly tries to procure happiness through the objects of the world, which have only a false glitter of joy. They can give, indeed, no enduring and everlasting satisfaction.
Our great religious books help to awaken and promote this dormant faculty in man. He need not run after the sense objects to attain some fleeting experiences of joy. He can get engaged in a more permanent and a fuller happiness, which is wholly independent of the availability of agreeable objects and environment.
(Source: Kindle Life by Swami Chinmayananda)