One of the most significant Roman Catholic theologians of the twentieth century and a formative influence upon Vatican II, Karl Rahner was born on March 5, 1904, in the city of Freiburg im Breisgau, Germany, the fourth of seven children in the family of Karl and Luise (Trescher) Rahner. Upon graduation from secondary school at the age of eighteen, Rahner followed in the footsteps of his elder brother Hugo and entered the Society of Jesus; he was to remain a Jesuit his entire life. During his novitiate studies from 1924 to 1927, Rahner was introduced to Catholic scholastic philosophy and to the modern German philosophers. He seems especially to have been influenced by the work of Joseph Maréchal (1878–1944), the Belgian philosopher and Jesuit, whose adoption of Kant's transcendental method in his five-volume work, Le point de départ de la métaphysique, had led to somewhat of...