"The founder of modern religious existentialism and the founder of psychoanalysis could not have known one another. Kierkegaard died one half year before the birth of Freud, and it is very unlikely that Freud ever read any of Kierkegaard's works. Yet the two have much more in common than their lifelong preoccupation with the phenomenon of anxiety. The elucidation and treatment of the problem of anxiety in the works of both thinkers — who knew nothing of each other’s work — leads to most surprising results. They confirm each other in their conclusions; they criticize each other in their limitations; and they match each other perfectly."