In a disordered mind as in a disordered body soundness of health is impossible.

It is now possible to quantify people's levels of happiness pretty accurately by asking them by observation and by measuring electrical activity in the brain in degrees from terrible pain to sublime joy.

But what is after all the happiness of mere power? There is a greater happiness possible than to be lord of heaven and earth that is the happiness of being truly loved.

To desire and strive to be of some service to the world to aim at doing something which shall really increase the happiness and welfare and virtue of mankind - this is a choice which is possible for all of us and surely it is a good haven to sail for.

Knowledge of what is possible is the beginning of happiness.

Happiness serves hardly any other purpose than to make unhappiness possible.

Indeed man wishes to be happy even when he so lives as to make happiness impossible.

The essence of philosophy is that a man should so live that his happiness shall depend as little as possible on external things.

The secret of happiness is this: let your interests be as wide as possible and let your reactions to the things and persons that interest you be as far as possible friendly rather than hostile.

Unquestionably it is possible to do without happiness it is done involuntarily by nineteen-twentieths of mankind.