“The difference between an optimist and a pessimist? An optimist laughs to forget but a pessimist forgets to laugh.”

“The difference between school and life? In school, you're taught a lesson and then given a test. In life, you're given a test that teaches you a lesson.”

“They say a person needs just three things to be truly happy in this world: someone to love, something to do, and something to hope for.”

“Both optimists and pessimists contribute to society. The optimist invents the aeroplane, the pessimist the parachute.”

“The the question whether I am a pessimist or an optimist, I answer that my knowledge is pessimistic, but my willing and hope are optimistic.”

“Still, Fritz was an optimist, and Karl was a pessimist, and that makes all the difference in the world.”

“Don't ever become a pessimist, Ira; a pessimist is correct oftener than an optimist, but an optimist has more fun--and neither can stop the march of events.”