Optimism is an outlook on life such that one maintains a view of the world as a positive place. It is the philosophical opposite of pessimism. Optimists generally believe that people and events are inherently good, so that most situations work out in the end for the best. A common conundrum illustrates optimism-versus-pessimism with the question, does one regard a given glass of water, filled to half its capacity, as half full or as half empty? Conventional wisdom expects optimists to reply, "Half full," and pessimists to respond, "Half empty" (assuming that "full" is considered good, and "empty", bad). Another paradox sometimes associated with optimism is that the only thing an optimist cannot view as positive is a pessimist. Pessimism, however, as it acts as a check to recklessness, may even then be viewed in a positive light.

The term panglossianism describes baseless optimism of the sort exemplified by the beliefs of Pangloss from Voltaire's Candide, which are the opposite of his fellow traveller Martin's pessimism and emphasis on free will. The phrase "panglossian pessimism" has been used to describe the pessimistic position that, since this is the best of all possible worlds, it is impossible for anything to get any better.

For more supplemental information about the Arden's production of Candide, download the Study Guide.