The Concept of Anxiety
The Concept of Anxiety (): "A Simple Psychologically Orienting Deliberation on the Dogmatic Issue of Hereditary Sin", is a philosophical work written by Danish philosopher Søren Kierkegaard in 1844. The original 1944 English translation by Walter Lowrie (now out of print), had the title The Concept of Dread. "The Concept of Anxiety" was dedicated "to the late professor Poul Martin Møller". He used the pseudonym Vigilius Haufniensis (which, according to Kierkegaard scholar Josiah Thompson, is the Latin transcription for "the Watchman" of Copenhagen) for "The Concept of Anxiety".
Paul Tillich
Two of Tillich's works, "The Courage to Be" (1952) and "Dynamics of Faith" (1957), were read widely, including by people who would not normally read religious books. In "The Courage to Be", he lists three basic anxieties: anxiety about our biological finitude, i.e. that arising from the knowledge that we will eventually die; anxiety about our moral finitude, linked to guilt; and anxiety about our existential finitude, a sense of aimlessness in life. Tillich related these to three different historical eras: the early centuries of the Christian era; the Reformation; and the 20th century. Tillich's popular works have influenced psychology as well as theology, having had an influence on Rollo May, whose "The Courage to Create" was inspired by "The Courage to Be".