"Virtue is simply happiness, and happiness is a by-product of function. You are happy when you are functioning"

"I feel happy to terrify kids"

"The man who makes everything that leads to happiness depends upon himself, and not upon other men, has adopted the very best plan for living happily. This is the man of moderation, the man of manly character and of wisdom"

"Happiness is not a state to arrive at, but a manner of traveling"

"There is only one person who could ever make you happy, and that person is you"

"I was married to Margaret Joan Howe in 1940. Although not a scientist herself she has contributed more to my work than anyone else by providing a peaceful and happy home"

"Action may not always bring happiness; but there is no happiness without action"

"Happiness is not a reward - it is a consequence. Suffering is not a punishment - it is a result"

"Knowledge of what is possible is the beginning of happiness"

"Happiness depends more on the inward disposition of mind than on outward circumstances"

"It is not true that suffering ennobles the character; happiness does that sometimes, but suffering for the most part, makes men petty and vindictive"