Existentialism, philosophical movement or tendency of the 19th and 20th centuries. Because of the diversity of positions associated with existentialism, a precise definition is impossible; however, it suggests one major theme: a stress on individual existence and, consequently, on subjectivity, individual freedom, and choice.Most philosophers since ancient Greek thinker Plato have held that the highest ethical good is universal. Nineteenth-century Danish philosopher Søren Kierkegaard reacted against this tradition, insisting that the individual's highest good is to find his or her own unique vocation. In terms of moral choice, existentialists have argued that there is no objective, rational basis for decisions; they stress the importance of individualism in deciding questions of morality and truth. Most existentialists have held that rational clarity is desirable wherever possible but that life's most important questions are not accessible to reason or science.
Freedom of choice, through which each human being creates his or her own nature, is a primary theme. Because individuals are free to choose their own path, existentialists have argued, they must accept the risk and responsibility of their actions. Kierkegaard held that a feeling of general apprehension, which he called dread, is God's way of calling each individual to commit to a personally valid way of life. Relatedly, 20th-century German philosopher Martin Heidegger felt that anxiety leads to the individual's confrontation with the impossibility of finding ultimate justification for his or her choices.
