“Pessimists are usually right and optimists are usually wrong but all the great changes have been accomplished by optimists.”
“Optimists are usually inexperienced.”
“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.”
“I'd rather be an optimist and a fool than a pessimist and right.”
“The pessimist complains about the wind; the optimist expects it to change; the realist adjusts the sails.”