<metaphysics> otimism is something of a "marginal" term in philosophy, in the sense that it is not really used in technical philosophy (when it is used, it refers to Leibniz's belief that this is "the best of all possible worlds"). The term is useful, however, since it describes a metaphysical affirmation of the possibility of knowledge and happiness in opposition to pessimism. In this sense, for example, eudaimonism can be a form of optimism. The popular usage of optimism is related to the meaning described here, but it is not as fundamental or "metaphysical".
See also meliorism Recommended Reading: Gottfried Wilhelm Leibniz, Theodicy: Essays on the Goodness of God, the Freedom of Man, and the Origin of Evil, ed. by Austin Marsden Farrer (Open Court, 1988) and The Cambridge Companion to Leibniz, ed. by Nicholas Jolley (Cambridge, 1994).
based on [A Dictionary of Philosophical terms and Names]
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