“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.”
“I am neither an optimist nor pessimist, but a possibilist.”
“The difference between an optimist and a pessimist? An optimist laughs to forget but a pessimist forgets to laugh.”
“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.”
“I'd rather be an optimist and a fool than a pessimist and right.”