that is fed, on the one hand, by his love of "music as form" and by his early readings of Augustine, Dionysius the Areopagite, Thomas Aquinas, and John Henry Newman. From his early musical training he came to appreciate the contrapuntal theme of a unity and rhythmic interplay of opposites. On the basis of his reading of Augustine, who speaks of God as both interior and superior to the soul, Przywara presented the Catholic concept of God in terms a mysterious simultaneity and interplay of divine immanence and transcendence. From Dionysius he came to emphasize God's "dazzling darkness", thereby giving his doctrine of analogy a final, apophatic stress. From Aquinas, beginning with his study of Thomas's De ente et essentia, he appropriated the fundamental ontological distinction between essence and existence and the equally important distinction between primary and secondary causality (secondary causation). Finally, from Newman he appropriated the idea of "opposite virtues", as seen, for example, in the complementarity of "loving fear" and a "fearing love," to which one must add his reading of Goethe, the Romantic philosophy of Franz von Baader, the Jewish sociologist Georg Simmel, and the Protestant theologian Ernst Troeltsch. All of these influences helped him to formulate his doctrine of analogy in more dynamic terms as a "dynamic polarity" – a polarity that registers both the creaturely tension between essence and existence as well as the tension between divine immanence and divine transcendence. Thus for Przywara the term "analogy" came to be more or less synonymous with what he also calls "unity-in-tension". Various engagements As a synthesizer of Catholic tradition, Przywara was one of the first Catholic theologians to engage creatively and critically with the modern world, defending Catholicism on two main fronts: one philosophical, the other theological (and ecumenical). On the philosophical front, he was one of the first Catholic thinkers to engage modern phenomenology, in particular the philosophies of Edmund Husserl, Max Scheler, and Martin Heidegger. On the theological front, he was one of the first Catholic theologians to engage in dialogue with Karl Barth, opposing Barth's early theology with the analogy of being as the Catholic answer to Protestant dialectics. He was, moreover, one of the first Catholic theologians to engage in dialogue with Jewish rabbis in Essen and Frankfurt, corresponding both before and after the war with the chief Berlin rabbi, Leo Baeck. However, his early attempts at constructive engagement with some