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.

I’m a pessimist because of intelligence, but an optimist because of will.

I am by nature an optimist and by intellectual conviction a pessimist.

I'm a pessimist about probabilities, I'm an optimist about possibilities.

A pessimist is one who makes difficulties of his opportunities and an optimist is one who makes opportunities of his difficulties.

You see, you are an optimist and live on hope. I am a pessimist and live on experience.

"What is an optimist? The man who says, "It's worse everywhere else. We're better off than the rest of the world. We've been lucky." He is happy with things as they are and he doesn't torment himself.

What is a pessimist? The man who says, "Things are fine everywhere but here. Everyone else is better off than we are. We're the only ones who've had a bad break." He torments himself continually."

A pessimist is a man who thinks all women are bad. An optimist is a man who hopes they are.

I can't be a pessimist because I am alive. To be a pessimist means that you have agreed that human life is an academic matter. So, I am forced to be an optimist. I am forced to believe that we can survive, whatever we must survive.

An optimist is a person who sees a green light everywhere, while the pessimist sees only the red stoplight. The truly wise person is colorblind.

Contrary to what you may assume, I am not a pessimist but an indifferentist—that is, I don't make the mistake of thinking that the resultant of the natural forces surrounding and governing organic life will have any connexion with the wishes or tastes of any part of that organic life-process. Pessimists are just as illogical as optimists; insomuch as both envisage the aims of mankind as unified, and as having a direct relationship (either of frustration or of fulfilment) to the inevitable flow of terrestrial motivation and events. That is—both schools retain in a vestigial way the primitive concept of a conscious teleology—of a cosmos which gives a damn one way or the other about the especial wants and ultimate welfare of mosquitos, rats, lice, dogs, men, horses, pterodactyls, trees, fungi, dodos, or other forms of biological energy.

The optimist believes that this is the best of all possible worlds, and the pessimist fears that this might be the case.

As stated earlier, I am a pessimistic optimist, or what I like to call a "pissed-omist." This is a person who has lived long enough to know not to expect much from most people or life in general, but still allows him- or herself the hope that somewhere under all the horseshit there may possibly be a pony.

The pessimist waits for better times, and expects to keep on waiting; the optimist goes to work with the best that is at hand now, and proceeds to create better times.