“Sometimes a pessimist is only an optimist with extra information.”

“To the optimist, pessimists are neurotic; to the pessimist, optimists are deluded.”

“Optimists and pessimists differ only on the date of the end of the world.”

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

“Between the optimist and the pessimist, the difference is droll. The optimist sees the doughnut; the pessimist the hole! ”

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

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

“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.”

“The optimist sees the donut, the pessimist sees the hole.”

“A stumbling block to the pessimist is a stepping-stone to the optimist.”