"I feel lucky, happy and philosophical about it all"

"I feel happy to terrify kids"

"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 the only good. The time to be happy is now. The place to be happy is here. The way to be happy is to make others so"

"Happy is the person who knows what to remember of the past, what to enjoy in the present, and what to plan for in the future"

"No man is happy who does not think himself so"

"No man is happy but by comparison"

"Try to be happy in this present moment, and put not off being so to a time to come, as though that time should be of another make from this which has already come and is ours"

"You will never be happy if you continue to search for what happiness consists of. You will never live if you are looking for the meaning of life"

"Great effort from great motives is the best definition of a happy life"