Abstract
This paper analyzes Kierkegaard's Religiousness A sphere of existence, presented in his edifying works, and Heidegger's concept of authenticity, proposed in Being and Time, as responses to modern nihilism. While Kierkegaard argues that Religiousness A is an unsuccessful response to modern nihilism, Heidegger claims that authenticity, a secularized version of Religiousness A, is a successful response. We argue that Heidegger's secularization of Religiousness A is incomplete and unsuccessful, that Heidegger's later work offers a reconsideration of the problem of modern nihilism, and that later Heidegger suggests a way out of nihilism which is compatible with Kierkegaard's Religiousness B sphere of existence