Existentialism

Existentialism is the philosophical and cultural movement which holds that the starting point of philosophical thinking must be the experiences of the individual. Moral and scientific thinking together do not suffice to understand human existence, so a further set of categories, governed by "authenticity", is necessary to understand human existence. ("Authenticity", in the context of existentialism, is being true to one's own personality, spirit, or character.)

Existentialism began in the mid-19th century as a reaction against the then-dominant systematic philosophies, such as those developed by Hegel and Kant. Søren Kierkegaard, generally considered to be the first existentialist philosopher, posited that it is the individual who is solely responsible for giving meaning to life and for living life passionately and sincerely ("authentically"). Existentialism became popular in the years following World War II and influenced a range of disciplines besides philosophy, including theology, drama, art, literature, and psychology.

Existentialists generally regard traditional systematic or academic philosophies, in both style and content, as too abstract and remote from concrete human experience. Scholars generally consider the views of existentialist philosophers to be profoundly different from one another relative to those of other philosophies. Criticisms of existentialist philosophers include the assertions that they confuse their use of terminology and contradict themselves.

Read more about Existentialism:  Definitional Issues, Opposition To Positivism and Rationalism, Existentialism and Religion, Existentialism and Nihilism, Etymology