Existentialism (// or //) is a form of philosophical inquiry that explores the problem of human existence and centers on the experience of thinking, feeling, and acting. In the view of the existentialist, the individual's starting point has been called "the existential angst," a sense of dread, disorientation, confusion, or anxiety in the face of an apparently meaningless or absurd world. Existentialist thinkers frequently explore issues related to the meaning, purpose, and value of human existence.
Existentialism is associated with several 19th and 20th-century European philosophers who shared an emphasis on the human subject, despite profound doctrinal differences. Many existentialists regarded traditional systematic or academic philosophies, in style and content, as too abstract and remote from concrete human experience. A primary virtue in existentialist thought is authenticity. Søren Kierkegaard is generally considered to have been the first existentialist philosopher. He proposed that each individual—not society or religion—is solely responsible for giving meaning to life and living it passionately and sincerely, or "authentically".