This is a reprint of a brief essay originally published in 1951. Hayek looks back on the age of liberalism and its collapse. During the generations of growing darkness, there were a few figures who bridged the age of liberalism and the postwar revival of its ideas and values. Hayek identifies three as particularly important, Edwin Cannan, Ludwig von Mises, and Frank H. Knight, and he briefly treats their works, circles, and students. He also briefly treats the circle of Ordo liberals in Germany.