"In those who rest on their unshakable faith, pharisaism and fanaticism are the unmistakable symptoms of doubt which has been repressed. Doubt is not overcome by repression but by courage. Courage does not deny that there is doubt, but it takes the doubt into itself as an expression of its own finitude and affirms the content of an ultimate concern. Courage does not need the safety of an unquestionable conviction. It includes the risk without which no creative life is possible."