"It takes great wit and interest and energy to be happy. The pursuit of happiness is a great activity. One must be open and alive. It is the greatest feat man has to accomplish"

"It is a useless life that is not consecrated to a great ideal. It is like a stone wasted on the field without becoming a part of any edifice"

"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"

"Behind every great fortune lies a great crime"

"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"

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

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

"Happiness is where we find it, but rarely where we seek it"

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