Karl Rahner (Freiburg, 1904 - Innsbruck, 1984) in 1922 entered the Society of Jesus and was ordained in 1932. He received his Ph.D. in philosophy with a thesis on the Spirit in the world (1939), which sought to revitalize, in relation to Heidegger, traditional metaphysics. Later, his thinking was extended to other fields of theology and Christology, ecclesiology, ecumenism, political action, spirituality and Christianity anonymous. He was professor of dogmatic theology and philosophy of religion in Innsbruck, Vienna, Munich and Münster. He was appointed consultant theologian of Vatican II and a member of the international commission of theologians. Among his numerous books include Foundations of Faith, published in Herder, Writings of theology and hearer of the word.