Existentialism is a tradition of philosophical enquiry associated mainly with certain 19th and 20th-century European philosophers who, despite profound doctrinal differences, shared the belief that philosophical thinking begins with the human subject — not merely the thinking subject, but the acting, feeling, living human individual. While the predominant value of existentialist thought is commonly acknowledged to be freedom, its primary virtue is authenticity. In the view of the existentialist, the individual’s starting point is characterized by what has been called “the existential attitude”, or a sense of disorientation, confusion, or dread in the face of an apparently meaningless or absurd world.