In The Blue Cross by G.K. Chesterton, the good, although somewhat simple, Father Brown easily identifies a famous thief, Flambeau, despite his disguise of clerical garb. Flambeau cannot comprehend how a “bumpkin,” a “turnip” endowed with the bumbling, rumpled vagueness stereotypical of the British priest (that is, the British priest of fiction) saw through his masquerade.

It was, replied Father Brown, owing to his being “a celibate simpleton.” A man “who does next to nothing but hear men’s real sins is not likely to be wholly unaware of human evil.” Supporting Brown’s knowledge of human nature is his scholastic training—the false-cleric Lambeau “‘attacked reason,’ said Father Brown. ‘It’s bad theology.’”

How typical of Chesterton to convey serious thought beneath the avuncular; here he borrows from Thomas Aquinas, for whom the faith’s teachings on morality are the same judgments at which unaided reason, functioning properly, would arrive. Attacks on reason are bad theology—at least according to Catholicism, which holds that one should be, in the words of John Finnis, “willing to argue out all questions of moral . . . conduct and decision with all the intellectual resources one can get” through unaided, natural reason.

As Finnis explains, the moral teachings of the faith “must pass the test of inherent reasonableness.” Certainly a person may affirm a moral judgment because he believes it to be revealed, but he ought also to affirm (and seek) the reasonableness of that moral judgment. Consequently, continues Finnis, moral questioning seeks a “reflective equilibrium” between dogma and “what would be judged morally reasonable even without revelation” (although neither dogma nor morality, if true, is revisable). Reflective equilibrium is not a matter of fudging dogma or tweaking morality until we find them comforting but rather comes to understand how they are true, with revelation and reason shining light on each other, bringing both to further intelligibility while maintaining fidelity to each.

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It is commonly thought that Christianity and the Enlightenment existed in opposition, as was argued by Peter Gay, a historian of an earlier generation:

Christianity claimed to bring light, hope, and truth, but its central myth was incredible, its dogma a conflation of rustic superstitions, its sacred book an incoherent collection of primitive tales, its church a cohort of servile fanatics as long as they were out of power and of despotic fanatics once they had seized control.

Of all the versions of Christianity, Roman Catholicism was thought the least amenable to Enlightenment, the most intransigent and incorrigible of all, with its promiscuous miracles and saints, transubstantiation, and centralized authority, to name but a few.

But as Ulrich L. Lehner argues in his new book, The Catholic Enlightenment: The Forgotten History of a Global Movement, “there has been a dramatic change in perspective” in the decades since Gay announced that “perhaps I exaggerated a bit when I hinted . . . that the Enlightenment is responsible for everything that is good about the twentieth century. Still . . . ” Gay’s emphatic “still” reveals his proclivity for Enlightenment over and against religion. But Lehner, with an impressive display of scholarship, tells a different story, one in which “only a small fraction of Enlighteners [were] anti-religious,” working instead for “a balanced relationship between reason and faith.” While many criticized religious hierarchies, most were convinced that “new discoveries in science and philosophy should renew the faith,” a position common across national and confessional lines. With (perhaps intemperate) optimism, Enlighteners “believed they could create a more tolerant society, more efficient government, more effective education, improved morals, and greater happiness,” but not by exorcising religious belief.

Still, as Lehner admits, the Enlightenment has seemed more obviously allied with Protestantism than with Catholicism. Indeed, Lehner’s earlier inquiries into the relationship between Catholicism and the Enlightenment had been met with bemusement or skepticism, for everyone “knows” Catholics “did not believe in science, that they were superstitious . . . never great supporters of democracy . . . subjugated women . . . helped destroy the Native American population,” and so on. Even if it is necessary to qualify Gay’s exaggerated claim that Enlightenment was responsible for all good, the Christian religion, and Catholicism in particular, could be thought responsible for the bad.

According to Lehner, reality is far more complex. Many historians did not bother to learn whether “only anti-religious thinkers were enlightened” or whether Catholic enlightenment “would be a contradiction in terms.” Governed by a false assumption, history was lost, neglected, although the Church itself is somewhat to blame, claims Lehner, for retreating into an anti-modern intellectual ghetto after the French Revolution. If one studies carefully, though, one discovers that many thinkers were Enlighteners because they were Catholics, and the Church was at times more enlightened that the Enlighteners in rejecting arranged marriages, prohibiting domestic abuse, advocating the dignity of women and indigenous peoples, and so on.

Drawing upon a vast range of literature from around the globe, Lehner explains the seriousness with which Catholics, including many clergy, advocated the new science, philosophy, and biblical criticism; curbed excesses of superstition (his section on vampires was especially intriguing) and unlikely miracles; advocated reform in both secular and Church governance; encouraged toleration and religious freedom; and protected the most vulnerable. At times, Enlighteners and Catholics worked together, to defend unborn life and alleviate poverty, for example.

Although it will surprise some contemporary readers, Catholics were markedly more humane than the Enlighteners with respect to the treatment of women. For instance, it is an ongoing slander that Catholicism views women as “birthing machines” and allows the procreative good to swamp the unitive good of married sexuality. That’s not true now, and it certainly wasn’t true then: it was French Enlighteners who advocated the supposed duty, owed to the state, to bear children, while the Church “always despised the secular population growth agenda,” encouraging “intimacy and companionship.”

In science and philosophy, politics and society, then, the Enlightenment and the Faith could and did bring mutual intelligibility to each other, showing no intrinsic incompatibility—“faith cannot collide with enlightened reason,” Lehner reminds us, for truth cannot contradict truth. On this reading, Enlightenment excess, particularly in France, was responsible for the perceived hostility. What could have been reflective equilibrium became unthinkable after the Terror, with revolutionaries decapitating nuns and monks and organizing the “genocidal killing” of the pious citizens of the Vendée. In response, “the conclusion was drawn that all Enlightenment, egalitarianism, and democratization were dangerous,” while Catholic reformers were viewed as untrustworthy. Church leaders judged liberal individualism the “original sin of the French Revolution,” and a strongly Ultramontanist viewpoint dominated in which freethinking Catholics could not find a home.

For Lehner, Catholic Enlighteners wanted to continue earlier Tridentine reform in keeping with the best of modern thought, aiming to make faith as attractive as possible. At the same time, they had the tendency to derail theology into serving the state, or, worse, heterodoxy. As such, in Lehner’s judgment, the Catholic Enlightenment can serve “as a lesson and potential guide for twenty-first century theology in its continuing dialogue with modernity.” Just as the Catholic Enlighteners “sought to show the public that they could successfully grapple with their intellectual counterparts,” so, too, the contemporary Church senses “reform . . . in the air” and can learn lessons from a past time “of turmoil,” realizing “that a self-content church that is not dynamically reaching out beyond the pews is doomed to wither away.”

I agree, but stress that genuine reform is always judged by the standards of the Church. While Catholic Christianity has a high view of nature, welcoming the best of Greek, Roman, Renaissance, Enlightenment, and contemporary thought, as also various folk pieties in ways thought scandalous or even syncretic to certain versions of Protestantism, the first task of the Church is to be the Church, not to satisfy the demands of its cultured despisers. Catholicism has learned and borrowed, developed and reformed, but it ought not forget that modern thought and society are undergoing a profound crisis. Europe seems without the will to live, either demographically or culturally. Emancipatory liberalism has emerged from easygoing nihilism into a rabid and destructive phase. Our universities are unsure of their purpose, the humanities appear incapable of anything other than endless critique, anticulture is prevalent, suspicion dominates, and technocratic society is fundamentally incapable of governing itself or providing sufficient reasons to live and serve the common good.

It’s very odd that just as the fruits of Enlightenment appear exhausted, many continue to clamor for the Church to open its windows and doors to let in the supposed fresh breeze of modernity. (I don’t claim this is true of Lehner.) That breeze has gone stale, and has been stale for some time now. Reflective equilibrium is a mutually illuminating enterprise, and while Catholicism respects the due autonomy and integrity of nature, the world, and the secular state, without any need to control or supplant them, it now appears time to illumine the world rather than to be illuminated, at least on what matters most to human well-being and to the human future.

The Church is a field hospital for the wounded. While an inward-looking Church is doomed to fail, a genuinely outward-looking Church offers healing to the ill. Looking outward can only mean bringing in the wounded so that they might be healed; since many modern wounds are self-inflicted, it ought not mean looking outward to embrace the wounding principles of modernity. Excessive individualism, sexual revolution, a callous and damaging gender ideology, a culture of death, confusion, boredom—these are exacerbated by certain excesses of modern thought. The task of the Church is to retain fidelity so that it can offer hope, healing, good news, redemption, and a Catholic Humanism more in keeping with the dignity of the human person than anything now on offer from the heirs of Enlightenment.

In the back and forth of reflective equilibrium, it’s much more the time to correct than to be corrected. The Church needs enough confidence in its own message to proclaim itself even as it welcomes the best the world has to offer—and to pick up and repair the shattered pieces and souls of the Enlightenment.