Something is amiss. For many years now, prominent voices have claimed that Western civilization is foundering. But if Western Civilization is sinking, on what has it run aground? Some say the Enlightenment is under attack, and we are witnessing human rationality driven in retreat—by an onslaught of religious faith that rejects modernity and the Enlightenment entirely—or by a resurgence of insular, tribal, and violent tendencies that are natural to human beings, and that have characterized most of human history. Others see the Enlightenment—its rejection of religious faith or of classical philosophy, ancient and medieval—as the problem. The solution (or a key part anyway) is the rejection of modernity. We ought to replace Hobbes, Locke, and Madison with Aristotle and Aquinas and maybe Wendell Berry. In both cases a sharp dichotomy is posed: either the Enlightenment or religious faith.

In Reason, Faith, and the Struggle for Western Civilization, Samuel Gregg offers a different account of our ills and the way forward. Faith and reason are the twin pillars of Western civilization, Gregg argues, and they came under attack in the late medieval period. The West’s predicament today is the product of pathologies of both faith and reason that are pulling these pillars apart.

Gregg begins his argument with Pope Benedict XVI’s famous Regensburg address. I think it best to begin there, too, though I want to bring into the foreground a thread that Gregg leaves a bit in the background, so as to help situate his argument. Benedict describes the fraying of the relation between faith and reason as the product of dehellenization, which commences with the Reformer’s rejection of medieval scholasticism. On the eve of the Reformation, before the publication of his Ninety-Five Theses, Martin Luther composed a “Disputation against Scholastic Theology” in which he claimed, “Virtually the entire Ethics of Aristotle is the worst enemy of grace.” According to Luther, Aristotle’s account of human happiness contradicts Christian doctrine. Consequently, the only way one can “become a theologian” is “without Aristotle”: “the whole Aristotle is to theology as darkness is to light.”

In response to Benedict XVI’s charge of dehellenization, Luther’s defenders might remind us that Luther’s view of the relation of Christianity to Greek philosophy is complex. After all, in his Heidelberg Disputation (1518), Luther’s predicates his rejection of Aristotle on an affirmation of Plato: “Aristotle wrongly finds fault with and derides the ideas of Plato, which . . . are better than his own.” “The mathematical order of things,” he adds, “is ingeniously maintained by Pythagoras, but more ingenious is the interaction of ideas maintained by Plato.” One could understand Luther as affirming an Augustinian Platonism against medieval scholastic Aristotelianism.

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But—I’d reply—Luther also affirmed a radical meta-ethical voluntarism according to which God’s omnipotent will alone constitutes the rule and measure of just and unjust, right and wrong. In Bondage of the Will Luther says, “God is He for Whose will no cause or ground may be laid down as its rule and standard; for nothing is on a level with it or above it, but it is itself the rule of all things . . . What God wills is not right because He ought, or was bound, so to will; on the contrary, what takes place must be right, because He so wills it.”

This rejection of the Thomistic synthesis paved the way for the affirmation of nominalism with respect to universals and the advent of mechanistic philosophy in the succeeding century. Thus, certain Reformers’ embrace of the via moderna, which took Ockham for its fountainhead, served as the ground for what some scholars call the modern turn—which, they say, culminated in the Enlightenment and triumph of reason over faith.

As Gregg sees it, however, the problem with certain modern currents (those that reduce what we can know to the deliverances of quantitative, observational science or empiricism or the views of John Stuart Mill) is not an emphasis on reason or rationality but, rather, the sundering of what Christianity joined. Indeed, insofar as the modern turn has rejected the Christian synthesis (Gregg holds that it did not do this entirely), rationality has been displaced with secular fideisms that abandon the grounds of any coherent account of the cosmos or human life.

How the West Was Built

As Gregg argues, Western Civilization was conceived in the marriage of Jerusalem and Athens. To Tertullian’s famous rhetorical question—“What has Athens to do with Jerusalem?”—Gregg answers, “Everything.” His answer runs counter to Tertullian’s affirmation of faith against classical philosophy, counter to those who see themselves today as the defenders of science against religion, and counter to the esoteric claim of Leo Strauss to see a mutually fruitful but irreducible and ineliminable tension between Athens and Jerusalem. Christianity involved the simultaneous embrace of both faith and reason.

Against those who see the faith part as coming from Jerusalem and the reason part as coming only from Athens, Gregg holds that the synthesis of faith and reason obtains first in ancient Judaism. As Gregg argues, Judaism de-divinized nature and rejected the notion that kings and rulers are divine. Contrary to the religions surrounding ancient Israel, Judaism also viewed the cosmos as an intelligible, created order rather than chaos, and taught that the material world that God created for humanity’s abode is good rather than malevolent. Drawing on Claude Tresmontant, Gregg writes, “The Jews’ liberation of human reason from mythology and nature-worship amounted to one of humanity’s most powerful ‘enlightenments.’” Lastly, Judaism affirmed human free will, which holds that human beings are morally responsible for their actions.

The contributions of Athens to human thought cannot be overstated. Yet, Gregg observes, certain obstacles blocked the full development of Greek rationality, including the lack of a conception of free will, the influence of Greek skeptics who thought the human mind could not (for the most part) get to the real truth of things, and Greek religion. The latter posited a universe comprising irrational deities, which contrasted sharply with the rationality of the cosmos that philosophers such as Pythagoras or Aristotle taught. Greek philosophy stood at odds with the gods of Mount Olympus as depicted by Hesiod and Homer.

Following Benedict XVI, Gregg notes that the encounter of Jewish religion and Greek thought predates Christianity. Educated Jews of the Diaspora, such as Saul of Tarsus, “were conversant with Greek thought.” The Jewish philosopher Philo “moved comfortably between the Hellenic and Jewish worlds.” Nevertheless, the hellenized Roman world and Judaism remained distinct. Romans and Greeks often viewed Jews as barbarians, just “because they weren’t Roman or Greek.” Christianity made the God of Abraham universally available (apart from conversion to Judaism or the performance of Jewish rites) while appropriating, adapting, and transforming the most important insights of Greek philosophy. The Christian revolution was a synthesis of reason and revelation—spurred by revelation itself.

The Christian revolution, according to Gregg, “stressed three ideas . . . influential in the development of Western culture.” First, Christianity emphasizes that divine reason—which became incarnate in Christ—created the world. Second, Christianity emphasized the faculty of natural reason by which all human beings are capable of coming to know truth, including moral truth. The Christian account of universal moral knowledge that St. Paul describes in Romans 2:13–15 entailed “a radical affirmation of the equality of everyone. . . . All were fully human and bore concrete [moral] responsibilities.” Third, the Christian revolution emphasized freedom. Christ’s distinction between what belongs to God and what belongs to Caesar entailed a limitation on civil government derived from divine law. Christ’s affirmation of free will—implied by his affirmation “that people were free to follow him or not”—entailed a limit on the authority of any person to tell others what to do. Christianity viewed freedom as a faculty humans possess for the sake of choosing truth.

Gregg discusses Justin Martyr’s synthesis of “biblical monotheism” and “Greek philosophy” as “the search for the ultimate foundations of reality,” and Clement of Alexandria’s affirmation of Christianity as “the true philosophy,” before turning to Albertus Magnus, Thomas Aquinas, and the High Middle Ages. “In no other culture,” he writes, “was this integration of faith and reason achieved for such a sustained period.” The medieval period created the university not only for the education of clergymen but also, says Gregg—drawing on Benedict XVI—for the pursuit of truth for its own sake—both in revelation and by means of reason. This pursuit was founded on the conviction that God is not irrational “but creative Reason.” The Christian “concern for reason” promoted inquiry “not only into theology but also into a multitude of other disciplines.” The Christian revolution did not launch an age that valued faith over and against reason. It launched an age that saw the world as “characterized by order, that the human mind can comprehend” and a world that “merits study” simply “because it is the work of God.”

How It All Unraveled

Certain currents in the Middle Ages threatened the synthesis. Franciscans tended to reject Greek thought. And voluntarism sundered the union of faith with reason by making good and evil arbitrary. Here Gregg mentions John Duns Scotus. He might also have mentioned William of Ockham, who radicalized the absolute power of God and contended that God can will anything, save violations of the law of non-contradiction and his own non-existence.

Some have viewed the Enlightenment as irreconcilably at odds with classical Christianity. Gregg, however, rightly rejects the notion of a monolithic Enlightenment that only advanced the primacy of reason and relegated faith to superstition. Isaac Newton may be the most important Enlightenment thinker. Yet Newton composed his Principia Mathematica “to refute what he regarded as the materialist assumptions underlying the theory of planetary movements proposed by . . . René Descartes.” Though heterodox in certain of his religious convictions, Newton thought that planetary motion and, indeed, the cosmos as a whole were governed by divine providence and final causation. Some Enlightenment thinkers did consider religion mere superstition (Voltaire, Frederick the Great of Prussia), or promoted skepticism (David Hume), but others preserved the conjunction of reason and religious faith (Johannes Kepler, Robert Boyle, Thomas Reid). Gregg concludes that defenders of the twin pillars of Western civilization should enter critical engagement with Enlightenment thought rather than rejecting it root and branch.

To be sure, some modern theorists followed certain Reformers in affirming nominalist metaphysics and voluntarist meta-ethics, which subordinated good and evil to arbitrary, omnipotent divine will. Thomas Hobbes and Samuel von Pufendorf are heirs to Luther’s (and Ockham’s) voluntarist account of good and evil. Other Enlightenment-era figures, however, emphasized the primacy of divine goodness. Thus, Gregg observes, Moses Mendelssohn “regarded the emphases on God’s goodness as his preeminent attribute as a recovery of ‘a fundamental insight that biblical and rabbinic Judaism first asserted against paganism.’” In this vein, I would add that the “modern” American founders and framers expressly grounded virtue and human moral obligations in divine goodness, thereby rejecting Luther’s and Ockham’s subordination of goodness to omnipotent will.

Other Enlightenment ideas were entirely at odds with Christian faith, including the claim that human beings can fashion and remake human nature or the reductionist claim that the only way to know anything at all is via the scientific method. Yet, as Gregg maintains, both claims are irrational. The first—that there is no fixed human nature—opens the “path to tyranny.” The second—that the only knowledge we can have is scientific knowledge gleaned via the scientific method—is itself not something amenable to scientific proof. It is a philosophical proposition. Indeed, as Gregg argues, the scientific method depends on antecedent philosophical claims necessary for the scientific method to have any justification at all. Scientism ultimately subverts reason itself.

Moreover, with Henri de Lubac, Gregg contends that certain influential and putatively secular ideologies that presented themselves as the deliverances of rationality and science truncate the scope of reason and ultimately tend toward fideism. While considering his position scientific, Karl Marx nevertheless “regarded the human mind’s capacity to know truth as extremely limited.” His collaborator, Friedrich Engels, maintained that “final and ultimate truths” are rare in the natural sciences and “final and ultimate” moral truth the “most sparsely sown” of all. Drawing on Eric Voegelin, Gregg writes, “after Marx decided that questions about man’s ultimate origins or the nature of good and evil were futile, he rapidly embraced the Promethean idea of man as his own creator.” The truncation of reason led Marx and Engels to create a secular ideology with the markings of a religious faith (and a fideistic one at that).

Marx, Engels, Auguste Comte (in his religion of humanity), and Mill (who affirmed Comte’s religion of humanity privately but refrained from affirming it in public) sought the replacement of traditional religious belief with ideas they considered rational and scientific, such as man’s ability to refashion human nature. But fracturing the synthesis of faith and reason ultimately culminated in Nietzsche’s rejection of reason in the name of self-creation. In The Gay Science, Nietzsche wrote, “it is still a metaphysical faith upon which our faith in science rests—that even we knowers of today, we godless anti-metaphysicians, still take our fire, too, from the flame lit by the thousand-year-old faith which was also Plato’s faith, that God is truth; that truth is divine.” Nietzsche understood that truth, God, Christianity, reason, and science stand or fall together. Affirming the death of God, if one is consistent, means giving up the objectivity of truth and the possibility of science. Moreover, the rejection of these went hand in hand with affirming the will to power and supermen who were freed from the shackles of Judaic and Christian slave morality and were capable of living beyond good and evil. The rejection of faith thus culminates in the rejection of reason and science.

Is There a Way Out?

Gregg holds there is no going back to a prior golden age. Moreover, following Benedict XVI, he refuses to reject the Enlightenment root and branch. Rather, our moment calls for rejecting the refrain that faith and reason are incompatible or mutually exclusive in any fundamental sense. We must recover the importance of Jewish and Christian revelation for the advancement of reason and science. Nietzsche is right that science and the Christian (and Jewish) view of God stand or fall together. But where Nietzsche would reject both, the restoration of Western civilization requires affirming both. It also requires affirming an orderly and intelligible cosmos created by a good God who made the human mind capable of understanding the world. In reaffirming the union of faith and reason, those who seek to restore Western civilization ought to draw not only on classical sources but also on those insights of modern science and the Enlightenment that cohere with the historic Western synthesis.

The restoration of Western Civilization from its present travails requires getting the story right. Here I have sought to situate Gregg’s argument and to highlight and bring to the fore some threads that bolster his already exceptionally compelling case. A good review doubtless proffers criticism as well. But, truly, I have none to give. I concur entirely (or almost entirely anyway). Indeed, Gregg’s Reason, Faith, and the Struggle for Western Civilization may be the most important recent work in this area, offering an important corrective to the other stories on offer.