An optimist is a person who sees a green light everywhere, while a pessimist sees only the red stoplight... the truly wise person is colorblind. Albert Schweitzer
Don't ever become a pessimist... a pessimist is correct oftener than an optimist, but an optimist has more fun, and neither can stop the march of events. Robert A. Heinlein
I am an optimist, unrepentant and militant. After all, in order not to be a fool an optimist must know how sad a place the world can be. It is only the pessimist who finds this out anew every day. Peter Ustinov
I have been judged to be a pessimist but what abyss of ignorance and low egoism is not hidden in one who thinks that Man is the god of himself and that his future can only be triumphant? Eugenio Montale