Happiness is often the result of being too busy to be miserable.

~   Unknown

Happiness is essentially a state of going somewhere, 
wholeheartedly, one-directionally, without regret or reservation.

~   William H. Sheldon

There is no fatigue so wearisome as that which comes from lack of work.

~   Charles Haddon Spurgeon

Happiness is mostly a by-product of doing what makes