The central proposition of Christianity is stupendous: the core of reality is a personal deity who loves you. Joseph Ratzinger explains:

At the very moment when the Magi, guided by the star, adored Christ the new King, astrology came to an end because the stars were now moving in the orbit determined by Christ… It is not the elemental spirits of the universe, the laws of matter, which ultimately govern the world and mankind, but a personal God.

It is the central proposal of the long intellectual career of Joseph Ratzinger—first as professor, then head of the Vatican’s office for doctrine, and latterly as Pope Benedict XVI—that rational enlightenment makes this proposition intelligible.

There is no one who does not have an opinion about faith and reason. Believers abound, but, in the West, non-believers predominate, and do so because of the Enlightenment. Some of your friends think the universe a bunch of rocks where brute forces prevail. The earnest amongst them believes these anonymous forces support something of value, humanity, but the less nostalgic reason that in a reality truly indifferent the best you can do is get on with life while you can. Your friends might never have heard of the Enlightenment, but they think the way they do because of it.

The reach of the Enlightenment is a problem for the Christian churches. Maurice Ashley Agbaw-Ebai, a priest and professor at Boston College, concedes the Enlightenment predominates: “as seen in the anonymous Kantians, Hegelians, Feuerbachians, and Nietzscheans, even in the pews.” Do the people in the pews really believe that three loving persons sit at the core of everything that there is?

German Enlightenment

Agbaw-Ebai thinks Ratzinger’s theology significant for its theory of rationality, one that evolved from close engagement with Enlightenment thinkers. The Enlightenment spread across Europe in the eighteenth and nineteenth centuries. Readers of Law & Liberty are well acquainted with the French and Scottish versions, and their role in the founding of the United States. Agbaw-Ebai contends the German Enlightenment is basic to Catholicism’s leading contemporary theologian.

The Bible, argues Ratzinger, has always been an Enlightenment. Many religions are terrifying. In Babylonian myth, Marduk, god of light, dismembers a dragon. The earth is part of this divided dragon, and we are dragon flesh, too. Reasonably enough, the Babylonian elite believed only dictatorial rule equal to the task of restraining the rages and resentments of the defeated dragon. By contrast, the Bible gives witness to Jesus, who called himself “truth, not custom.” God is revealed in the logos made flesh: the Greek word for a thinking that gathers up, collects, and sorts. The image of tending that resonates in logos explains why Mary Magdalene thought the resurrected Jesus a gardener (John 20: 15). A figure of tender reason, Jesus pushes the question of our being front and center. “The question of being, which is so slandered today, arose for no other reason than the desire for freedom, which cannot be divorced from man’s need for truth.” Christianity is a religion built on freedom and truth, its doctrine expressing an “inner rapprochement between Biblical faith and Greek philosophical inquiry.” The faith of Israel taking final shape in the orbit of Greek philosophy was, says Ratzinger, providential.

For those likingpostage stamps, this book has a pretty cover. It features a Vatican stamp with Pope Benedict, and a German, with Immanuel Kant. However, the encounter of Biblical Christianity and the German Enlightenment was not particularly pretty, in fact. Agbaw-Ebai observes that the German Enlightenment was not utterly hostile to religion. Critical and reformist, certainly, but a social role for religion was at least tolerated, unlike in France. From it, he argues, Ratzinger learnt to take history seriously. Nonetheless, the story of the German Enlightenment is one of Christianity’s marginalization.

Kant depicts human dignity as consisting in persons self-legislating, the individual alone with the moral law. Hegel thinks the Christian spirit a worthy prop for the psychological maturity of a rationally enlightened individual: “you fail to recognize man’s dignity and his capacity to derive from his own self the concept of divinity and the comprehension of the divine will. Whoever does not honor this capacity within himself does not revere the deity.” Feuerbach amplifies this view: the Christian god is a mirror image of the human spirit, Jesus a projection of a refined human mind. Humanity enthroned, Nietzsche kicks away the Christian scaffolding entire: self-assertiveness replaces humility, which is just the honest formulation of what the German Enlightenment was saying all along, he argues.

This German exaltation of humanity is, in fact, a kind of re-primitivism. The German Enlightenment fell apart in the mass horrors wrought by that country in the twentieth century. “The radical detachment of the Enlightenment philosophy from its roots,” concludes Ratzinger, “ultimately leads it to dispense with man.” The German cult of self was, in fact, a narrowing of reasoning: its mooring in the ideal of logos—a tending to—got completely lost. Ratzinger observes a parallel between the upshot of the Enlightenment and the liturgical year: “Does our century not begin to become one large Holy Saturday, a day of God’s absence, a day when icy emptiness grows even in the hearts of the disciples?” A catastrophic loneliness stalks the German ideal of a self-legislating rationality.

An illustration is Hegel’s gloss on the story of Jesus talking to the Samaritan woman at the well (John 4: 4-26). This passage includes the famous words, “salvation is from the Jews.” Hegel has Jesus’s say: “These alone are pleasing to him; their worship is authentic, being animated solely by the spirit of reason and its flower, the moral law.” In stark contrast to this ponderous lecture, the Biblical story is achingly intimate: “Many of the Samaritans from that town believed in him because of the woman’s testimony, ‘He told me everything I ever did.’” Hegel’s abstraction misses entirely the warmth of the love Logos has for the vulnerable woman: “To him who as Spirit upholds and encompasses the universe, a spirit, a man’s heart with its ability to love, is greater than all the milky ways in the universe” (Ratzinger). To avoid “icy emptiness,” reason needs a guardian, faith. Christianity, Ratzinger argues, clarifies that just as faith needs the crystalizing power of reason, so reason needs the softness of faith. Faith and reason envelop one another, and, in doing so, restrict one another. For all its sophistication, the German Enlightenment was utterly naïve about abstract reasoning, its consequences observable in racialism and eugenics, the atomic bomb, and the impacts of business metrics and medical dabbling on nature. As reason became ever more arid, sensibility shriveled: “The external deserts in the world are growing, because the internal deserts have become so vast.”

History and Creation

Agbaw-Ebai’s writing is direct and jargon-free. Inclusion of an index would help to navigate the book, but Light of Reason, Light of Faith has a clear structure. Large quotes from Ratzinger are followed by illuminative commentary. The commentary adds value, though is always deferential.

A high point is Agbaw-Ebai’s account of Ratzinger’s theology of creation. The footprint of the German Enlightenment is evident in Ratzinger’s history of the loss of the idea of creation. In Christianity, “the world emerges as a creation of God’s Reason and God’s Word. The sun and the moon are no longer gods, but lamps placed by God in the sky for the measurement of time.” Connoting dependence, creation is anathema to the German Enlightenment. Ratzinger chronicles the long slow decline of creation as a leading idea in the West. In the Renaissance, Giordano Bruno sought a return to the ideal of the Greeks, making God one with the cosmos. With a like gesture, Galileo over-emphasized the mathematical side of the Greeks, propagating the “unfeeling geometry of the universe.” At the start of the modern age, Luther cast out creation entire. For him, says Ratzinger, “grace is seen here in radical opposition to creation, which is marked through and through by sin; it implies an attempt to get behind creation.” Luther, as Ratzinger intriguingly puts it, is faith without ancestors.

This assault on creation laid the groundwork for the Gnosticism that would grip the German Enlightenment’s celebration of concepts. In Gnosticism, resurrection is not a solidaristic triumph over suffering, but a utopia of rationalism when self-sufficient mind finally corrects stupid biological misfirings. Gnosticism approaches suffering with concepts, rejecting, as Ratzinger puts it, “the mystery of suffering, of love, of substitutionary redemption, in favour of a control of the world and of life through knowledge.” Concepts replacing solidarity has baleful consequences: “A man who can no longer transcend the limits either of his consciousness or of his speech fundamentally can no longer speak of anything at all. The language of formulae, of the technical calculus, is the only thing left for him.”

Opportunity Missed

The final chapter of the book takes us from Ratzinger to Benedict XVI. Readers of Law & Liberty will likely wish Light of Reason, Light of Faith crescendo with the role of the German Enlightenment in Ratzinger’s papal contributions to Catholic Social Thought. Instead, it focuses on his ecclesiology and gives only a few hints of Benedict’s take on Gnosticism and transhumanism. This has become a core concern for the Church. Ratzinger had insisted on a distinction between the first and second Enlightenment. The first refers to the 17th century when thinkers like Descartes and Leibniz wrestled with the ideal of the human as imago Dei in the shadow of the invention of automatons. They did so within a framework of creation. However, by the eighteenth century, the Enlightenment had hardened, and in this second iteration displaced the imago Dei in favour of a deity made in the image of humanity. Later thinkers, “sought the exclusion of revealed religion to be replaced, at best, with rational faith, and at worst, with full-blown atheism that declared the death of God.”

The German Enlightenment was certainly guilty of this. “Reality, then, is change, and man’s task is to intervene in this process of change and himself create truth. From being the measure of man, truth now became his creature.” Echoed in our post-modern politics of truth, Ratzinger sees reason falling victim to what he calls party philosophy, reason made in the image of special interests. Ratzinger is fond of quoting the Russian thinker Vladimir Soloviev: “Demonism comes as rational planning, Lucifer is author of The Open Way to World Peace and Welfare.” It would be useful to see Agbaw-Ebai speculate on the role of this suggestive image in Benedict’s encyclicals.

Champion of the Weaker Party

The blurbs and Foreword to the book make much of Agbaw-Ebai as a young African theological talent but readers should not come to Light of Reason, Light of Faith looking for insight into the concerns of African Catholic theology. This is a respectful intellectual biography and Agbaw-Ebai keeps the focus on Ratzinger’s development admirably.

Theology, Ratzinger explains, is not a valorization of autonomy, but “turns to something we ourselves have not devised that is able to be the foundation of our life.” Christianity does not celebrate our innovations, but our solidarity. Agbaw-Ebai relays a story from Ratzinger’s autobiography, Milestones, about the near short-circuiting of his academic career. In the German system, someone hoping to teach at university must write an habilitation, a book beyond even their PhD research. Benedict wrote on St. Bonaventure—the great Franciscan philosopher theologian and contemporary of Aquinas—and his use of history. Benedict’s book is highly regarded. Opaquely, not all the readers of the thesis valued it, and only after professor interventions and re-writes was the text judged adequate. Grimly, almost all academics have a story about powerful teachers who tried to damage their progress. The experience helped Ratzinger formulate a rule of logos. “I made the resolve not to agree easily to the rejection of dissertation or habilitation theses but whenever possible—and respecting the integrity of the procedure—to take the side of the weaker party.” In the Enlightenment West, Catholicism is lucky to have Ratzinger in its corner, and now, Father Agbaw-Ebai, too.