pessimism, philosophical opinion or doctrine that evil predominates over good; the opposite of optimism. Systematic forms of pessimism may be found in philosophy and religion. In religion Buddhism and Hinduism pessimistically appraise the world, while Christianity's pessimism is more restricted. Numerous philosophers have been pessimistic, notably Arthur Schopenhauer in the 19th cent. and Martin Heidegger in the 20th cent.