Can Philosophy Be Christian?

The possibility of a Christian philosophy was fiercely debated in the late 1920s and the early 1930s, especially in France, where several distinguished historians of philosophy, including Émile Bréhier, vigorously denied that there had been, or could be, any such thing. It was, Bréhier said, as absurd as a Christian mathematics or a Christian physics. Genuine philosophy, in his opinion, had been suffocated by Christian dogma in the Middle Ages, and did not reemerge until the seventeenth century, when Descartes picked up about where the Greeks had left off.

The Catholic medievalist Étienne Gilson led the counterattack. He opened his Gifford Lectures on The Spirit of Medieval Philosophy with two chapters devoted respectively to the problem and the notion of Christian philosophy, which he defined as “every philosophy which, although keeping the two orders formally distinct, nevertheless considers the Christian revelation as an indispensable auxiliary to reason.” In a series of books and articles published over the next few decades, Gilson demonstrated the vibrancy of medieval philosophy. He convincingly argued that the biblical concepts of God, creation, history, and the human person had made a decisive impact on the whole history of modern philosophy.

In our own time, at least here in the United States, there seems to be a rather general recognition that Christians have a distinctive approach to philosophy. We have had since 1926 an American Catholic Philosophical Association, which now has some 1,200 members, but there was nothing equivalent for Protestants until 1979, when William P. Alston, Alvin Plantinga, and several of their friends established the Society of Christian Philosophers. Today, twenty-one years later, it counts more than a thousand members, and enrolls a rapidly growing number of younger scholars. It is thoroughly ecumenical in its constituency.

These initiatives, however, are scarcely typical of the university world, which finds the concept of Christian philosophy paradoxical, even nonsensical. Some philosophers simply rule out any consideration of revelation as lying beyond the purview of their discipline. Emotivists in the tradition of A. J. Ayer still dismiss religion as noncognitive. A host of agnostics, pragmatists, relativists, and deconstructionists, while differing among themselves, form a common front in opposition to revelation as a font of abiding truth.

Pope John Paul II, in his 1998 encyclical Fides et Ratio, shows himself acutely aware of the present intellectual climate. With his customary courage, he dares to challenge current trends in both philosophy and theology and in so doing raises the question of Christian philosophy in a new form. From the very beginning of the encyclical John Paul II reminds his readers that philosophy, in its etymological sense, means the love of wisdom (para. 3). Philosophy, therefore, is a human search for truth about ultimate questions (73); it is a journey awakened by wonder springing from contemplation of creation (4).

In a stricter sense, philosophy is a rigorous mode of thought; it elaborates a systematic body of knowledge in which the elements are held together in organic unity by logical coherence (4). Ideally the system should comprehend reality in all its dimensions, but the Pope acknowledges that no one system achieves this ideal. Because of the limits of the human mind and the particularities of human cultures, every philosophical system is partial and incomplete. For this reason philosophical inquiry holds primacy over philosophical systems (4).

Philosophy, according to the Pope, operates within the order of natural reason (9), using its own methods (49), which differ from those of theology. Although philosophers disagree among themselves about the methods of their discipline, they appear to be unanimous in holding that philosophy does not derive its proofs from the word of God received in faith.

Theology, by contrast, is “a reflective and scientific elaboration of the understanding of God’s word in the light of faith” (64). According to John Paul II, the starting point of theology is always the word of God given in history and accepted in faith (73). By “faith” he means a free, obedient, and deeply personal decision by which one entrusts oneself to God and acknowledges the truth of what God has revealed (13). The chief purpose of theology is to provide an understanding of revelation and of the content of faith (93). The heart of theological inquiry is the mystery of the triune God, which becomes accessible to faith through the Incarnation of the Son and the descent of the Spirit of truth upon the Church (93).

Christian philosophers have reached no agreement about how philosophy is related to faith. The classical positions fall into three main types.

According to the first school of thought, sometimes called Augustinian, there is a Christian philosophy, and in fact the only true and adequate philosophy is Christian. In the early centuries of the Christian era, apologists such as Justin and Clement maintained that Christianity is the true philosophy (38), but they seem to have been using the term “philosophy” in a broad sense as equivalent to human wisdom. In the Middle Ages, St. Anselm made a sharper distinction between faith and reason. Having accepted the existence of God and the fact of the Incarnation on authority in faith, he tried to demonstrate these truths by “necessary reasons” that would compel the assent of Jews and pagans who did not credit the authority of Scripture. He apparently considered that he had succeeded in this endeavor. Much later, rationalist philosophers such as Hegel contended that the mysteries of the Trinity and the Incarnation, initially accepted by faith, could be demonstrated by pure reason, at which point faith would no longer be needed in order to affirm them as true.

Hegel and his school, being rationalists, were convinced that reason is superior to faith. They integrated theology with philosophy by letting it be swallowed up by philosophy, but it is also possible to integrate the two disciplines to the advantage of theology. In the nineteenth century, the traditionalists, denying the autonomy of reason, held that all true philosophy was based on divine revelation, accepted in faith. In our own century Gilson came to the conclusion that in reasoning about God and things necessary to salvation “no one can pretend to reach truth unless he relies upon revelation to safeguard him against error.” The remarkable advances achieved by philosophy in the Middle Ages, he contends, were due to the guidance and enrichment it received from revelation.

While this view tends to merge the objects of philosophy and theology, it preserves a difference of method: theology proceeds by way of authority, whereas philosophy relies on evidence and intrinsic reasoning. Christian philosophy, as Gilson came to use the term, meant “the use the Christian makes of philosophical reason when, in either of these two disciplines [philosophy or theology], he associates religious faith and philosophical reflection.” According to Gerald McCool, Gilson understood Christian philosophy as the philosophical moment in Catholic theology. While retaining a formal distinction between the two disciplines, he argued that the Christian should not try to develop a philosophy independent of theology.

The second classical position is the direct contrary of the first. Instead of saying that philosophy must be Christian, the neo-Thomists of the Louvain school, following in the footsteps of Cardinal Désiré Mercier, held that philosophy must proceed rigorously by its own methods, without allowing itself to be influenced by faith. Fernand Van Steenberghen, representing this school, insisted that philosophy must be open on an equal basis to believers and nonbelievers. Christian philosophers, he contended, should not allow themselves to be isolated in a ghetto, as would occur if Gilson’s positions prevailed. (As Christian believers, Mercier and Van Steenberghen of course accepted revelation. They also insisted that it was possible to reflect on revelation in a scientific way. But such reflection, they maintained, was by definition theology, since it was done in the light of faith.)

While concurring with the rationalists that there could be no specifically Christian philosophy, the Louvain neo-Thomists rejected Bréhier’s negative assessment of medieval philosophy. The faculties of philosophy in the medieval universities, they maintained, achieved significant advances in the strictly philosophical field without allowing faith or theology to interfere with their autonomy. The same can be done by the believer today.

The two classical positions thus far described stand at opposite ends of the spectrum. The first school maintains that philosophy ought to be Christian, since it requires the positive influence of faith; the second school denies the possibility of Christian philosophy on the ground that philosophy must be a self-contained product of autonomous reason.

Between these two contrasting positions there are several mediating positions, which make up my third category. Jacques Maritain, differing only slightly from Gilson, argued that human reason, although limited in range, can achieve significant insights about ultimate questions without the help of revelation. Revelation attests to many naturally knowable truths such as the existence of God, the spirituality of the rational soul, and the dependence of the whole world on God’s creative action. In dealing with truths that can in principle be known both by revelation and by reason, Christian philosophers may allow faith to indicate where the truth lies, but as philosophers they are obliged to establish their conclusions by independent reasoning. Maritain concludes with a typically Scholastic distinction: philosophy can be Christian in the order of exercise, but not in the order of specification. Christian philosophy is philosophy itself conducted by a thinker who profits from revelation.

A second mediating position is that usually identified with Maurice Blondel. He held that neo-Thomists such as Van Steenberghen and Maritain treated philosophy too much as though it were a self-contained system, in which revelation could appear as a mere intruder. The whole supernatural order could then be written off by nonbelievers as an unnecessary superstructure over and above a self-sufficient world of reason and experience. As an alternative to this extrinsicism Blondel contended that philosophy, when it operates without any reference to faith, inevitably becomes aware of its own limits. It can discover within the human person a dynamism toward a goal that nature cannot reach and toward a truth that reason cannot discover. Blondel rejected the idea of a philosophy that would be Christian in the sense of being based on revelation, but he held that all sound philosophy, holding fast to its own principles, would lead to the threshold of revealed truth. It could thus be Christian in spirit and in orientation.

Henri de Lubac, developing a third mediating position, agreed with Gilson about the necessity for philosophy to be informed by Christian revelation in order for it to learn the most important truths of the natural order. Blondel, in his view, spoke too much as though the philosopher could begin in a void, without regard for tradition and culture. But in agreement with Blondel, de Lubac held that philosophy is affected by the natural desire for the supernatural; it is naturally Christian and is oriented toward revelation as its own completion. The positions of Gilson and Blondel thus correct and complete each other.

Building on these classical positions, John Paul II in Fides et Ratio distinguishes three states or stances of philosophy in relation to faith. He speaks of a philosophy prior to faith, a philosophy positively influenced by faith, and a philosophy that functions within theology to achieve some understanding of faith.

In describing the first state of philosophy, John Paul II accepts the thesis of Van Steenberghen and Maritain that there can be authentic philosophy outside of faith. Arguing rigorously from rational criteria, one can attain conclusions that are true and certain (75). In affirming this position, the Pope would seem to be on solid ground. Plato and Aristotle, while lacking the guidance of Jewish and Christian revelation, rank among the greatest philosophers of all time. They ably refuted sophistic errors such as materialism, relativism, and hedonistic pragmatism; they showed the capacity of reason to discern the intelligible features of the real order; and they laid a solid groundwork for the metaphysical principles of noncontradiction, sufficient reason, and causality.

John Paul II, however, does not settle for a closed system of rational knowledge. With Blondel and de Lubac, he is keenly aware that an autonomous philosophy cannot be self-sufficient. The journey of philosophy, he holds, cannot be completed without faith. Just as faith seeks understanding, so, conversely, understanding seeks faith (16–23). Philosophy, in perceiving its own limits, can serve as a preparation for the gospel.

This basically Augustinian position has roots that long antedate Blondel. Even before the Christian era, Plato recognized that there were pressing questions that the philosopher could not answer without the help of a divine revelation, which he himself did not claim to have received. In Plato’s Phaedo, Simmias confesses to Socrates the difficulty of attaining certitude about the fate of the soul after death. The wise man, he says, should take the best and most irrefragable of human theories and let them serve as a raft upon which to sail through life “not without risk, as I admit, if he cannot find some word of God which will more surely and safely carry him.”

The insufficiency of reason was expressed in another way by Immanuel Kant, who claimed that in showing reason’s incompetence to attain speculative certitude about questions concerning God, freedom, and immortality, he was making room for faith. Kant may have excessively minimized the scope of theoretical reason, and his conception of faith may have fallen short of Christian orthodoxy, but we may concur with his thesis that by recognizing the limits of reason we can better appreciate the need for faith.

Schooled in post-Kantian personalist phenomenology, John Paul II is deeply sensitive to the subjective component in human knowledge. Philosophy, as he sees it, is not so much a set of conclusions as a mode of inquiry (76). As I have said, it is first of all a process of exploration and only secondarily a matter of systematization (4).

Philosophy, in this Augustinian perspective, is not a dispassionate clinical inquiry; it has to be pursued with trust, commitment, and creative imagination. Again and again in his encyclical, John Paul II adverts to the unquenchable thirst for truth that God has implanted in the human heart (opening sentence and 29). Modern philosophy, he observes, has the great merit of focusing attention on the human spirit and its yearning to understand (5); human knowledge, he says, is a journey that allows no rest (18, 33). In the footsteps of Anselm, the Pope asserts that “the intellect must seek what it loves: the more it loves, the more it desires to know” (42). The philosopher should be driven by a passion for ultimate truth, a passion that faith can intensify (56).

The philosopher, considered in the order of actual existence, is no stranger to belief. Anyone who begins to philosophize does so as a member of a community that has received a body of beliefs and values transmitted from the past. Only after such views have been unreflectively assimilated does the philosopher bring critical inquiry to bear (31). The tools of critical reason have themselves been forged and refined in the philosophical tradition.

Even when embarking on the quest for new insights, reason is sustained by a certain primordial faith. The discoverer begins by assuming that the thirst for truth, so ineradicably rooted in the human heart, is not vain and useless. The sense that there is an answer waiting to be found sustains the confidence and perseverance needed to conduct the search (29). At this point in his encyclical the Pope speaks in terms reminiscent of the great philosopher of science, Michael Polanyi.

John Paul II, as I understand him, would agree with Blondel that the human spirit has an inbuilt restlessness toward the divine, an inner exigency for a supernatural message of salvation. But he would probably add, as de Lubac and Karl Rahner do, that philosophy would not be able to articulate the concept of the supernatural without help from revelation. When practiced in a Christian culture, philosophy receives its concept of the supernatural from the believing community.

The passage from autonomous philosophy to faith does not take place without a conversion. John Paul II is sensitive to the perspectives of Christian existentialism, typified by Søren Kierkegaard and Fyodor Dostoevski. The word of the Cross, he acknowledges, seems to crush and contradict the philosopher’s ideal of wisdom; the wisdom of the Cross challenges every philosophy (23). But truth cannot be incompatible with truth. “At the summit of its searching reason acknowledges that it cannot do without what faith presents” (42). In the final analysis, truth proves to be one: Christ, who calls himself the truth, brings the quest of philosophy to a surpassing fulfillment (34).

Our consideration of the insufficiency of autonomous reason brings us to the second state of philosophy, which arises after revelation has occurred and been accepted in faith. John Paul II agrees with those who hold that Christian revelation can make a valid contribution to philosophy, as may be seen from the examples of outstanding thinkers such as Thomas Aquinas. With Gilson and Maritain, he teaches that there is such a thing as Christian philosophy. The term, he says, serves “to indicate a Christian way of philosophizing, a philosophical speculation conceived in dynamic union with faith” (76). It includes important developments of philosophical thinking that would not have happened without the stimulus of the word of God (76).

The term “Christian philosophy” should not be restricted to the Middle Ages. John Paul II, as I understand him, would find it appropriate for the philosophical writings of the Cappadocian Fathers, Augustine, and other patristic authors, not to mention the Christian thinkers of modern times. Such philosophers as Locke, Leibniz, and Malebranche would be unintelligible without reference to their Christian faith.

Although John Paul II accepts the term “Christian philosophy,” he warns against certain misunderstandings. The term, he explains, does not mean that the Church has an official philosophy. It might have been thought a century ago that Thomism was the Church’s one philosophy, but the present Pope avoids taking that position. At the time of Leo XIII, he declares, it seemed that “renewed insistence upon the thought of the Angelic Doctor” was “the best way to recover the practice of a philosophy consonant with the demands of faith” (57). While encouraging recourse to the wisdom of Aquinas, John Paul II allows for a plurality of systems. Acceptable systems of philosophy, he believes, must share the metaphysical realism of St. Thomas, including his position on the natural knowability of the existence of God (53). The Angelic Doctor is an authentic model for all who seek the truth and who wish to profit from revelation without demeaning the just autonomy of reason (78). He evinced an exemplary passion in the search for objective truth (44) and exhibited admirable courage by tackling new problems and entering into dialogue with the Arab and Jewish thought of his time (43).

Among the great medieval philosophers John Paul II singles out the “great triad” of Anselm, Bonaventure, and Thomas Aquinas (74). He has words of praise for John Henry Newman, Antonio Rosmini, Vladimir Soloviev, and Vladimir Lossky (74), all of whom philosophized in the light of their Christian faith without being classifiable as Thomists. Although he does not mention Blondel and Max Scheler by name, he finds merit in the philosophy of immanence and phenomenology (59). While discountenancing an unprincipled syncretism, he is prepared to learn from alien philosophical movements, even those he finds dangerous and debilitating. “The currents of thought which claim to be postmodern,” he writes, “merit appropriate attention.” But they should not be allowed to destroy all certitude and inculcate a total absence of meaning (91).

In his reflections on Christian philosophy, John Paul II distinguishes between two kinds of benefit that faith confers upon it. The first is an influence on the thinking subject. Faith purifies philosophical reason in a twofold way. On the one hand, it cures philosophy of the pride to which it has at times been subject and with which it was reproached by Paul, Pascal, and Kierkegaard, among others. On the other hand, faith inspires philosophy with courage to tackle certain difficult questions, such as the problem of evil and suffering, that might seem insoluble except for the light cast on them by revelation (76).

The second influence of faith upon philosophy is objective. Revelation, as already mentioned, assists reason to discover certain truths that are in principle accessible to reason but might never be found in fact without revelation. John Paul II places in this category the ideas of creation as the action of a free and personal God; sin as an offense against God; the dignity, freedom, and equality of human persons; and the meaning of history as event (76).

The Pope at one point speaks of reason and faith being interior to each other (17). The relationship between them, he says, is circular (73). Revelation can assist philosophy by stirring it to explore unsuspected paths and by warning it against false trails.

Because of the intimate connection between philosophy and faith, the ecclesial Magisterium, in its ministry to faith, cannot ignore philosophy. It has a right and a duty to encourage promising initiatives and to warn against aberrations incompatible with the Church’s faith. This discernment should not be seen as an intrusion but as a service to right reason and to the philosopher’s quest for truth (50“51).

Thus far we have been speaking of philosophy as an independent branch of study, standing apart from theology even though influenced by it. Before concluding, we must consider philosophy in its third state, in which it functions within theology, which takes its departure from revelation received in faith. Revelation goes beyond reason in the sense that it contains many truths that philosophy cannot discover. These truths are strict mysteries, but they are not conundrums.

Revelation, since it comes from the divine Logos, is inherently intelligible (66). With the help of philosophy, the theologian can achieve a limited but nevertheless very fruitful understanding of such mysteries. Speculative theology makes use of philosophy in its reflection on revealed truths such as the processions of the Trinity, the union of the two natures in the person of Jesus Christ, and the concepts of guilt and atonement that lie at the basis of moral theology (66).

In connection with dogmatic theology, John Paul II refers to the hallowed term ancilla theologiae, which has a legitimate meaning even though it is subject to misunderstanding. The service rendered by philosophy, he says, is not a matter of servile submission to commands given by theology as a higher discipline. Rather, the term means that philosophy, while holding fast to its own principles, can be fruitfully used within theology (77). This utilization in no way impairs the proper autonomy of philosophy, for if philosophy were denatured, it could not perform its distinctive service. One of the benefits of sound philosophy is to show that the truth of dogmatic formulas is not tied to any particular time or culture, as some have imagined (95“96). Truth is universal by its very nature (27).

To amplify somewhat the Pope’s teaching on dogmatic theology, it may be helpful to recall several points of traditional teaching from Thomas Aquinas and the First Vatican Council. Although reason cannot prove the existence or even the possibility of strict mysteries such as the Trinity and the Incarnation, it can expose the errors of those who attempt to demonstrate their impossibility. Philosophical reason, furthermore, can show the analogies between the orders of nature and grace; it can exhibit the internal coherence of the whole supernatural order as revealed by Christianity, casting light on each revealed truth by manifesting its harmony with other revealed truths and with the goals of human existence. Meditation on the data of revelation can show, finally, that the truths of faith fulfill those aspirations of the human heart which, as Blondel showed, cannot be satisfied by anything within the order of nature.

In terms of the debates of the 1930s, John Paul II’s positions differ from those of all the principal contestants. To the basic question whether there is such a thing as Christian philosophy he answers, against Bréhier and Van Steenberghen, that there is. Against Blondel, he holds that such philosophy is Christian in its substance and content, not simply in its orientation. Against Gilson, he holds that there can be a valid philosophy that is not influenced by revelation, and that the Christian philosopher need not be a theologian. And finally, against Maritain he contends that Christian philosophy can be practiced in a variety of styles, and is not necessarily Thomistic. On the whole, the Pope’s positions coincide most closely with those of de Lubac, who sought to mediate between Blondel and Gilson.

Even if John Paul II had done nothing more than to sort out what is and is not acceptable in the earlier positions, his encyclical would be sufficient to establish a new state of the question. But he also takes a positive step forward. In Fides et Ratio and in several of his unofficial writings before and after he became Pope, he expresses his view that personalist anthropology must stand at the center of Christian philosophy today. The philosophy of consciousness, developed according to phenomenological method, can throw new light on the subjectivity of the person, which stands at the basis of culture, civilization, and politics. Biblical revelation has taught Christian philosophers such as Gabriel Marcel and Jewish philosophers such as Martin Buber and Emmanuel Lévinas that the whole of human existence is a coexistence in dialogue, and that the primary dialogue partner is the God of our faith.

Personalist phenomenology, practiced according to the principles of the Lublin school of Thomism, can contribute to a much needed renewal of metaphysics (83). The forms of metaphysics that were still flourishing in the 1930s are languishing today. The battle is no longer between Cartesian rationalists, German idealists, and Catholic neo-Scholastics. Many contemporary philosophers, proclaiming the “end of metaphysics” (55), are embracing agnosticism, relativism, and consequentialist pragmatism, or devoting their energies to purely formal questions concerning language and hermeneutics (5, 47, 81“82). Theology, for its part, all too often evades the challenge of truth. Falling into fideism or sheer positivism, many theologians limit themselves to sociological, linguistic, and historical studies of the Bible and Church teaching (48, 55, 61, 94). Both theology and philosophy are therefore in need of conversion. They must alike regain their sapiential dimension.

Fides et Ratio is a pressing appeal for faith and philosophy to “recover their profound unity which allows them to stand in harmony with their nature without compromising their mutual autonomy” (48). Once the distinction of goals and methods is in place, the intimate association between the two disciplines can be restored. Understood no longer as closed systems but as inquiries aimed at ultimate truth, they can be seen not as rivals or enemies, but as allies. The old debates about the turf belonging to each discipline and about their respective preeminence need not greatly trouble us today. The current need is for dialogue and mutual support.

Faith and reason, as described by John Paul II, are united like the two natures of Christ, which coexisted without confusion or alteration in a single person. Christian wisdom, similarly, involves a synthesis of theology and philosophy, each supporting and benefiting the other. The Pope also uses an analogy from Mariology: just as Mary, without impairment of her virginity, became fruitful by offering herself to the Word of God, so philosophy, he says, can become more fruitful by offering itself to the service of revealed truth (108).

Integral Christian wisdom, which sometimes goes by the name of philosophy or theology, draws on the full resources of reason and revelation alike. It is exemplified by the intellectual projects of Augustine, Bonaventure, and Thomas Aquinas, who sought to achieve a universal wisdom by synthesizing the totality of knowledge under the auspices of faith. Vatican II taught that “faith throws a new light on everything,” thus making it possible for the believer to reflect not simply on the word of God but on the whole of life from the perspective of the word of God (Gaudium et Spes 11). In particular, the mystery of the human person takes on new meaning in the light of Christ, who is the key, the focal point, and the goal of all human history (GS 10).

Fides et Ratio begins with the statement that faith and reason are the two wings on which the human spirit soars to the contemplation of truth. The entire encyclical is an inspiring summons to the pursuit of a wisdom in which theology and philosophy are harmoniously integrated to the advantage of both and the detriment of neither.

The program set forth in the encyclical is radical and bold, especially in view of the troubled climate of the academic world today. Philosophers and theologians who wish to implement the Pope’s vision must resolutely struggle against mighty odds. But a measure of success is attainable, especially in universities that stand within the Christian tradition. That success may also be a key element in John Paul II’s strategy for the new evangelization. By reestablishing the harmony between faith and reason, it can help to prepare for the new springtime of faith that is envisaged as Christianity enters its third millennium.

Avery Dulles, S.J., holds the Laurence J. McGinley Chair at Fordham University. This essay is adapted from a McGinley Lecture delivered by Father Dulles in New York City.