“The pessimist says, ‘It can’t get any worse!’ And the optimist replies, ‘Oh yes it can!”
“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.”
“[A] pessimist gets nothing but pleasant surprises, an optimist nothing but unpleasant.”
“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.”