"A pessimist might initially seem like someone who bears the burden of expectation too thoroughly. But in reality the opposite is the case. The pessimist expects nothing - thus he or she is more truly open to every possibility as it presents itself. A pessimist can recognize and delight in the fact that we live in a world of surprises - surprises that can only strike the optimist as accident and mishaps, disturbing as they do a preordered image of the world's continuous improvement. This openness to the music of chance lends to the pessimist an equanimity that might strike an outsider as callous. The optimist, on the other hand, must suffer through a life of disappointment, where a chaotic world constantly disturbs the upward path he feels entitled to tread."
Joshua Foa Dienstag "Pessimism: philosophy, ethic, spirit" (Princeton UP, 2006)