Existentialism is the twentieth century philosphy that stresses the individual's freedom as a self-determining agent responsible for his choices and their authenticity. It holds that the notion that a person has an essential --that is inherent -- determinative self is an illusion -- that existence preceds and determines essence, so that one's self is nothing more or less than what one has become and is at any given moment, the sum of the life one has shaped to that point. Central to this idea of essence is the view that each person is free at each moment, always able to choose how to act or not to act. But each decision affects the future by liiting later choices. To see the truth about our lives is to recognize that the human condition is absurd because our existence has no meaning other than the fact itself. Both inspite of an because of this absurdity, the induvidual must create his own meaningful personal morality. The person of good faith, despite the lonely anguish of attempting to achieve authenticity, does not withdraw from this effort but is fully engaged in it.