Jacques Maritain Center: Thomistic Institute

Faith and Reason: Aquinas's Two Strategies

Cyrille Michon
1999 Summer Thomistic Institute
Jacques Maritain Center, University of Notre Dame

Fides et Ratio is an Encyclical concerned mainly with philosophy. It is not a philosophical text, and contains formally no argument. But it enuntiates and defends many theses, concerning the powers of reason, and so of philosophy, which are not broadly accepted nowadays. They are very similar, if not identical, with Aquinas's views, which are not broadly accepted either. This seems to be a problem, for both, and for one who engages himself in philosophy while trying to be faithful to the catholic Magisterium.

The Encyclical contains at least three modes of speech. One is descriptive -- of the present situation in philosophy and theology, and of the history of the links between faith and reason. One is parenetic, and gives advices, most of them positive: encouragements to philosophers, scientists and theologians. And one is evaluative, and gives an appreciation of the different forms taken by those speculative disciplines. To my mind, the second mode of speech is the most original. I would just like to single out the emphasis on the climate of friendship the Holy Father asks philosophers, and specially christian philosophers, to create in their debates (n.33) [1], because this is precisely what Ralph McInerny allows us to do during those days. In some countries, perhaps more than in the US, this is very uncommon, and so very appreciated. But the third mode of speech is certainly the most important: description leads to evaluation, and counsels derive from it. It is also the most delicate, because an authoritative voice seems to enter the field of free rational inquiry.

I would like to comment on the two uses of reason related to faith that are recommanded by the Pope, which are exactly those defended by Aquinas. And so I would like to discuss in some way the presence of thomism in the Encyclical. I know the subject is very tricky, and I know this audience is very informed. So these remarks should be taken with a pinch of salt, as coming from one who tries to find his way in philosophy, and for whom Aquinas is here a terminus a quo more than a terminus ad quem. I will focus on what I have called Aquinas's two strategies. This will need a first step in which I try to summarize what he says about faith that seems to me to be relevant in that perspective. I will then make some comments on FR and Aquinas.


"What we believe we owe to authority, what we know (understand) we owe to reason" [2]. Augustine's slogan is hardly avoidable. It is not on this augustinian formula that Aquinas dwells in order to define what it is to believe, but the formula is welcome [3], and it has the merits of underlining a crucial distinction: that of the basis on which something is accepted. We know that p in virtue of the meaning of p, or of what p says, and, eventually, of our direct, sensible knowledge of the world, and/or of other known propositions. But we believe that p on the basis of who says that p. It is the identity of the sayer, not the content of what is said, which is now the motive for accepting p. As such, the distinction is not one between religious belief, or faith, and reason, but it opposes two propositional attitudes, belief and knowledge. Religious belief can only be seen as a subspecies of belief so defined.

In fact, Aquinas has tried to justify two well known definitions of religious belief: one of the act of credere, and one of the habitus, and in that case virtue, of faith, fides. Following another augustinian formula he defines credere, as cum assentione cogitare [4]. This definition presupposes a distinction between the act of cogitating or, more precisely, of considering considering[5] some (propositional) content and the act of assenting to it. For a content p, there may be different motives for which one assents to it; recalling the preceding formula, we could say: if it is authority, we have belief, if it is reason, we have knowledge or understanding. But, as such, this would no more characterize religious belief, and Aquinas proceeds in a different way: on the basis of the distinction between consideration of a content and assent to it, he distributes different propositional attitudes [6].

(1) In doubting, the intellect considers a content, but is not inclined to assent to, nor to dissent from it [7]. (2) The intellect may be more inclined to assent than to dissent, without being totally determined, and this can be (2.1) because it has only light motives, which is the case of suspicion, or (2.2) because of the fear that the other part of the contradiction be the good (true) one, which is the case of opinion [8]. (3) The intellect can also be totally determined to one part of the contradiction, but the determination can be provoked (3.1) by the content to which one assent, or (3.2) by the will. In the first case, the assent can be prompted (3.1.1) immediately, by the very fact of understanding the terms out of which it is composed, as in the evidence of the first principles ("the whole is greater than the part"), and Thomas calls it intelligence (intellectus),or (3.1.2) mediately, if the content considered as to be refered to others which will function as premises for this content as consequence. Such a disposition is called science. Finally (3.2), the assent is not prompted by consideration of the content alone, nor with consideration of other contents. The investigation of reason goes on without finding sufficient motives. If assent is given this must be because of a motion of the will. And Thomas adds that the will moves because one finds some convenance or utility in such an assent. We have here the act of credere, sharply distinguished from all others [9].

It is not at all clear that credere is concerned only with what we would call matters of faith or religious belief. Nothing in the definition points towards a religious content, that of christian Revelation, nor towards any divine intervention in the process of believing. I do not know whether Aquinas would accept those additions to his definition, and so distinguish two kinds of beliefs: one which could have any content, and could also be false, and one which could only have a revealed truth as content. Perhaps would he maintain that non religious beliefs can always be counted as instances of what he calls "opinion". That would have as a consequence that there would be no assent totally determined to a false content, e.g. Noe's firm opinion that it no more rains, while it is still raining. And it would also imply that no opinion (in Thomas's sense) could be motivated by will, e.g, there could be no such thing as Noe's opinion that it no more rains as caused by his desire that it be the case. Perhaps should we take those criteria (total determination and motivation by the will) as forming a conjunction which is in itself defining (necessary and sufficient) but whose elements are not when taken separately. But this would go against Thomas's own words.

In fact, when we follow the texts order, it seems that Thomas has been speaking of the religious act of believing, because he then introduces fides, as the habitus whose acts are acts of credere [10]. Thomas knows that there are grounds for calling "faith" some dispositions to believe others with reference to no religious contents. This "human faith" is indispensable to social life, and is manifested in promises, testimonies and son on. But that is not what he will call "faith". Faith is defined by the Hebrews Epistle's phrase (11, 1): substantia rerum sperandarum, argumentum non apparentium, and Thomas adds that this a completissima diffinitio [11], though an obscure one [12]. This time, the content of what is believed is part of the definition, and it can be shown that those hoped things are the matter of christian Revelation. Thomas shows also how the distinct notes of the definition make faith being different of science and intelligence (which do not bear on what is not appearing), of opinion and doubt (which do not rely on any kind of argumentum), and from human or common faith, which does not bear on what one hopes.

But this definition still does not mention any necessary divine intervention, and does not make it clear, for example that faith, though a virtue, is also a gift, and that man is unable to believe without God's grace. Thomas could answer that those precisions are true, but unnecessary to single out faith from the other propositionnal dispositions, as they were not necessary to single out the act of credere from the other propositionnal acts. It seems to me that he nevertheless introduces those characteristics when it is useful. In particular, he must add that in faith (disposition or acts) the assent we give to the particular content is due to a certain light, lumen quoddam, which is the habitus fidei, divinely infused in our minds [13]. This habitus, or lumen fidei, coming from God, as a sigillatio primae veritatis in mente, does not move per viam intellectus but more per viam voluntatis: it does not make us see the truth, as in intellectual evidence, but it makes us assent to it, voluntarie, without compelling our will. We can thus gather all the elements which seem to be necessary for a complete and clear definition of faith: this is a virtuous disposition to assent to a propositional content referring to hoped things, in which the intellect is moved by the will, and the will by God's grace.

We must admit two components of faith, and a twofold divine origine of faith. 1) The objective component is the content of Revelation, which comes from God through the prophets, and is accessible to all: it is public, and not reserved to the happy few. It has been called, after Aquinas, the fides quae (creditur). 2) The subjective component is the habitus which makes the believer believes this content, and it comes from God who infuses it in each particular believer, so that it is a private gift, and not given to all but to some. This is what Aquinas calls faith, and what has also been called the fides qua (creditur). Thomas compares this light of faith to the knowledge of principles: both are infused, but the second in all human beings, the first in some only. And he compares the fides quae, the contents proposed to our acceptance, to the sensible evidences: fides is ex auditu. Both elements are needed, in human knowledge, sensible experience and light of first principles, in faith, the content revealed and the infused habitus. Considerations of the christian existence, of the faith as virtue, as informed by charity, as an encounter between man and God, or between man and Christ, are certainly all the more important, from our and from God's point of view. But it is inescapable that there is no sense in the idea of the light of faith given to someone, without a content to be believed. Faith, in the subjective sense, is said to be man's response to God's revelation -- faith in the objective sense. The fides qua presupposes the fides quae.

This content can be, and has been, summed up in formulas. They are the articles of faith. The shortest list consists in two parts: God'existence and His Providence, or Christ's divinity and humanity [14]. We recognize here the greek couple of theologia and oikonomia. Of course, the well known symbols of the faith proposed by the Church to our profession can also be considered as a perfect summary of the fides quae [15]. But we can also include all dogmatic definitions, and all the content of the Scripture. To all those contents we can assent by the virtue of faith. But in order to assent, we must be able to consider, and understand prima facie what those articles mean. So faith presupposes reason. Only a rational being can be a believer. Only one who understands the content of the fides quae can receive the habitus of the fides qua. What may be controversial is the space left to reason apart from being a capacity to understand the revealed words and articles. We have seen that in faith, the basis on which the content on the fides quae is accepted is authority. Were it not authority, there would be no more faith. That is why faith disappear with vision, and that is why, for Aquinas, there is no faith where we have science. Believed (creditum) is opposed to seen (visum) as well as to known (scitum).


Here we come to the announced two strategies. Aquinas argues that reason is not only presupposed by faith in order to understand the content of Revelation, but that we can also assent to part of this content on the basis of reason alone, and that we can, once those articles are believed, draw rational conclusions from them. Using mainly Aristotle's achievements, Thomas maintains that part of the fides quae can be accepted not by the virtue of faith, but by the work of natural reason. This part of Revelation can be known and not believed. And for Aquinas, this part is not small: it includes the existence of God, many of His attributes, the spirituality and immortality of the human soul, and a large part of what the Bible says of divine Providence and commandments, in particular the content of the Decalogue. Are excluded from this potentially known part of Revelation the mysteries of the christian faith, as the nature of the divine Trinity, the Incarnation of the Son, and his work of Redemption, continued in the Sacraments. Those articles of faith could not be established on the basis of reason alone. Only one who accepts the Revelation, and so only one who has been given the fides qua, can assent to those articles [16].

Faced with the content of those articles, reason is not confined to the sole capacity of grasping them. Two uses of reason are still in place. The first one is the refutation of all argument that would go against the content of faith. As truth is one, there can be no opposition between its grasping by faith and its grasping by reason [17]. So, an argument which would run contrary to faith must be unsound, and reason must be able to show it. This does not mean that reason should be able to establish the denial of its conclusion (an so the truth of the article denied), but that it could discover the logical failure in the inference, or the falsity in the premises, and so the non necessity of this conclusion. Thomas's position on the question of the eternity of the world is a case in point: reason cannot establish the truth believed by faith (i.e that the world has a beginning), which is not a necessary but a contingent truth, but it can show that every argument to the contrary is inconclusive, and so that it has no necessity either. Generally, though not in this last case, reason can also give probable arguments in favour of what is believed [18]. The second use of reason relative to articles which can only be held by faith is the drawing of conclusions from them taken as premises [19]. In so doing, reason can establish some necessary consequences deriving from the revelation, or some necessary links between the articles of faith, in short, different rationes fidei, as Anselm called them.

Those distinct works of reason are mentioned in a famous quodlibetal question disputed during Aquinas's second parisian teaching, in 1271. Being asked whether the theologian should use only authority in theological disputes, his answer makes a distinction between two kinds of disputes. One kind of dispute, adressed to non believers, is given the scope of answering the an sit question. It must establish the fact of the matter, quia est. The master can and even must use all authorities available for such a purpose. But, disputing with a non believer, only are available thoses authorities accepted on both parts. Some accept all the Bible, some only one of both Testaments, and some no textual authority, so that only natural reason can be used [20]. The second kind of dispute, which is the one we find in theological schools, and where the master adresses those who yet believe what the question is about, has the purpose of giving them an understanding of what they believe, an intellectus fidei. Authorities are of no use here, they would leave the interlocutors empty [21]. This intellectus is reached through the second work of reason we have been examining earlier.

I would now suggest that the two strategies here defined fit very well with the two comprehensive syntheses of the catholic faith Thomas wrote.

The first strategy, whose purpose is to establish the fact of the matter, is accomplished in the Summa contra Gentiles. The best title is Book on the Truth of the Catholic Faith Against the Errors of the Infidels [22]. And in fact, Thomas is only concerned with questions intrinsically related to matters of faith. The book tries to establish the truth and to refute all the errors that have been committed on those points (I, 2, §2). Thomas, in a text very similar to the one quoted from the Quodlibets, explains that he will use all kinds of authorities. But that some interlocutors, the muslims, do not accept any kind of authority, and so they will only accept purely rational argumentation (ibid. §3). The plan of the book is clear: Thomas will first establish all the truths that can be reached by reason alone, and then those that cannot (I, 9, §3). The first part includes the first three books, and, if Thomas is true to himself, it implies that the content of books I-III is apt to be known rather than believed. I have no space here to discuss Thomas's fidelity to his plan [23]. Book III, on Providence, goes very far in attributing to natural reason the power to establish the necessity of grace for man to reach his end, which cannot be a natural end, and even the necessity of glory in the afterlife. Not only that, but Thomas also establishes this necessity for angels (whose existence is not demonstrated but shown to be very convenient) [24]. And in moral matters, he not only argues in favour of the content of the Decalogue, but he also defends on purely natural grounds the legitimity and usefulness of religious vows [25].

The second part of the CG, book IV, is in charge of establishing the truths contained in the christian Revelation which are unaccessible to natural reason alone. As previously announced, it will proceed from authorities. But a little look suffices to see that Thomas is not only quoting authorities in order to establish those truths. This is even little part of book IV. A large part is concerned with the refutation of heresies by rational arguments taking authorities as premises, and as far as possible, authorities that are accepted by the adversary. And the largest part of book IV is concerned with arguments to show the possibility or even the convenience of the revealed truths, and with drawing conclusions from them, following the arguments of the predecessors, specially those of the councils, or building new explanations, in order to characterize, for example, the attributes given to Christ according to His two natures (27-44), the links between the Holy Spirit and the human soul (20-22), the reasons for not following the Greeks in their restrictive understanding of how to celebrate the Eucharist (67-69), or the putative qualities of the resorted bodies (82-89), to give a few examples.

Is it to say that book IV engages in the second kind of dispute? The purpose was to establish the truth of the catholic faith. And it was announced that authority would be used, when reason would become unable to do the job. But Thomas also said that reason would still be used in order to refute the errors and to give probable and no more necessary arguments (I, 9, §3). I take it that book IV has the purpose of arguing according to the two kinds of disputes, but that the CG, as a whole, is more arguing according to the first one. And I would suggest that the Summa theologiae fits more with the second dispute. The last thomistic synthesis of christian doctrine is explicitly adressed to beginners in theology, and so to believers [26]. The purpose of the Summa is to give them an understanding of what they believe, and not to establish what they believe yet. As a matter of fact, the structure of an article in the ST, as we know, firmly distinguishes the argument taken from authority in the sed contra from the the rational argument in the corpus. That is to say that no authority is given as a basis for assent in the body of the article. There, only rational argumentation is in place, and the conclusions of the responses are justified along the lines of this argumentation. This is not to say that the rational argumentation is free from all authorities. Authority is not given as a make-believe, but authorities are invoked implicitly when the argument takes as premisses an article of faith which is not demonstrable by natural reason.

This occurs many times, for example, in the questions on the Trinity in the first part, in the different questions on the gifts of the Holy Spirit in the second part, and in most of the questions of the third part. Though the differences of order with the CG may appear very slight, they are nonetheless significant: the double mode of truth is no more the main principle of organization, not even a secondary principle. Of course, Thomas's discourse and arguments are almost the same from one Summa to the other [27], but the difference is a difference of scope: that of the two kind of disputes. Even the revealed truths that are accessible to reason are rationaly demonstrated as they were in the CG, the first one being the existence of God. But it now is not a question of establishing the otherwise believed truth that God exists, it is more an exercise of understanding faith which tells us that God exists and that God's existence can be reached by natural reason. We could say that the CG uses philosophy and aristotelian metaphysics as a preamble to faith, and as part of theology in order to establish the truth of the catholic faith [28]. But the ST uses reason, and aristotelian metaphysics, in order to reach the intellectus fidei, and this seems to be more a philosophy of faith.

If we limit ourselves to the work of reason in order to establish or in order to understand the content of faith, we can assimilate Aquinas's two strategies to the two forms of theology accessible to us. Aquinas often distinguishes two different modes of the knowledge of God, or of theology in the broad sense of sermo de deo. The first one goes from us, or from the created world, to God, and the second one comes from God to us. This can be directly, as in the case of the beatific vision, or indirectly, as in the case of faith to divine revelation through the prophets. We could call the first theology, "natural theology", because it needs natural reason alone, the second one "glorious theology", because it needs the light of glory, and the third one "gracious theology", because it needs the gift of grace [29]. In our present situation, only the first and third theology are available to us. The principal, twofold distinction is thus sufficient, N. Kretzmann calls them "theology from the bottom up" (natural theology) and "theology from the top down" (gracious theology). But both theologies are also forms of rational argumentations about the most fundamental aspects of reality. That is why we could also take them as two uses of philosophy, one striclty limited to natural premises, the other admitting also supernatural premises. Both argue along the same lines, and with the same philosophical background, in Thomas's case aristotelian philosophy [30].


Now, both strategies and theologies are extensively recommended by Fides et Ratio, whose insistence on the necessity of metaphysics cannot be underestimated [31]. I remarked at the beginning that this is a very controverted statement. I would like to ask three questions related to this perfect agreement between Aquinas and the Encyclical, and disagreement of both with so many others. I will mainly restrict myself to considerations concerning metaphysics within the first strategy, that of natural theology, because it is presupposed by the gracious theology.

The first question could be labelled the question of the thomism of the Encyclical. We noted that FR does not develop any kind of philosophical argument, and so the question is more that of the coherence with, and the positive evaluation of, St Thomas'attitude and teachings. There are three explicit mentions of those teachings in the Encyclical [32]. The last one (§78) gives Aquinas as the best example of the synthesis of faith and reason which respects the legitime autonomy of both. The first one (§43-45), during the historical survey of the links between faith and reason, which gives a preeminent place to St Thomas, underlines the same feature, but is much more precise on the role of Aquinas for the use of pagan philosopohy in christian theology, grounded on a conception of nature as accomplished by grace, and of faith as presupposing an exercise of thought, and leading to a form of supernatural knowledge. And it refers to the two kinds of wisdoms, philosophical and theological, distinguished according to the double mode of truth, but united by the unity of Truth. This is a true thomistic point, though not exclusively. Another, not exclusively, thomistic point is the mention of Aquinas'realism and philosophy of being, to which I come back. Lastly, in the chapter on the interventions of the Magisterium in the philosophical domain, the subsection entitled "The Church's interests for philosophy" (§57-63) recalls the different advices given by this Magisterium in favour of St Thomas, and more specially of St Thomas's philosophy. His attitude concerning the relations between faith and reason is mentioned, but rapidly, and the role played by those advices on the historical studies and editions of Aquinas's works, and on the renewal of thomism and neothomism is also remembered. But there, a mention of other forms of christian philosophies is made, without precise references, but with the label of "the great tradition ot the christian thought in the unity of faith and reason" (§59).

At this point, we could conclude that the Encyclical makes more references to Aquinas than to any other, though it does not exclude philosophers and theologians coming form other traditions of thought. Aquinas's theses in the fields of philosophy and theology are not canonized, so to say, but his conception or the relations between faith and reason is. However, this conception cannot be totally independent of other philosophical views. And the Encyclical not only affirms at length the necessity of the study of philosophy, in the praeparatio fidei (§61), but it defends [33] 1) the preeminence of philosophy among the different forms of knowledge, because of its sapiential function, 2) an epistemic realism or doctrine ot objective truth as end of knowledge, and 3) the idea of the metaphysics of being, which can be taken for another formulation of epistemic realism (when opposed to philosophy of appearance, n.44 in fine), but which is also referred to the ability of the human mind to reach some parts of the Revelation as the existence of God, the immortality and freedom of man, the objectivity and universality of moral values.

If we add to this the fact that philosophy is presented as needed by theology in its investigation of Revelation itself, it appears that Aquinas's two strategies, or two ways of uniting faith and reason, are explicitly reassumed. Of course, epistemic realism and a broad notion of metaphysics are not enough to characterize Aquinas's philosophy. Even Descartes's philosophy would be well adapted to FR's requirements. At that level of description, there is no big difference between Aquinas and Descartes. Both consider that philosophy can reach a part or the revelead truths, and both give to philosophical argumentation a good place within theology, though both have not developped it at equal length. It would not be so easy to characterize other philosophers among those mentioned explicitly or implicitly by the FR. And the fact is that those two theses, on the powers of natural reason in natural and in gracious theology, are now largely denied, outside and inside christian thought. So I leave here the question of the thomism of the Encyclical, for a more intriguing one: how can the Magisterium enjoin the philosophers to accept any particular thesis, or, from the other point of view: how can a philosopher accept any particular thesis on the basis of authority?

Almost all of non christian thinkers, and many of them, do not accept today the thesis of human capacity to reach those truths as God's existence, and the soul's immortality. It is not possible here to give an overview, neither useful, because the Encyclical recognizes it (chapter V, specially n.55 and n.61). I think therefore that it should be considered as an uncontroversial statement that a great majority of philosophers do not accept Aquinas's and Decartes' conception of the powers of natural reason. Now, for a christian philosopher, even though, as christian, he holds as true the assertions of God's existence and of individual immortality, those assertions may not appear philosophically well grounded. Without holding them as false on the basis of rational arguments -- which would put him in a double truth situation -- , he can profess, and many do profess, philosophical agnosticism, while professing also a firm faith in those two articles. The first attitude is based on rational considerations only, the second one on authority. Now, there is a problem with the exercise of authority concerning not only truths, but the way those truths should be reached, when this way is natural reason. The rationaly agnostic but firmly faithful christian philosopher could obey the injunction not to profess his philosophical agnosticism. But how could he obey the injunction of rationaly reaching, or of accepting on rational grounds only, those truths? How can he accept any kind of rational demonstration, or even any kind of rational understanding, of what he is rationaly doubtful? And if that is not possible, what sense can it have to make this injunction?

In fact, the Encyclical teaches (and so enjoins to believe and profess), that this reaching is possible, but does not say how. The agnostic christian philosopher is in the following situation: he firmly believes that p (e.g. there is a God), he finds no rational grounds for p, but yet, following the Magisterium's teaching, he firmly believes that there are such grounds and that, as a rational being, he is able to find them. Should he not ask the Magisterium, who affirms those two points, to show him those grounds? The answer is in the text (n.76): it is not the Magisterium's task to tell which argument, nor which philosophy (as a large body of coherent concepts, descriptions and arguments), give the grounds. It only says that there are such grounds, not which are such. And this can be firmly held by faith, without compromising the legitime autonomy of reason and philosophy [34]. It is only if the Magisterium said that this particular argument should be accepted as demonstrative, or as rationaly sufficient, that it would introduce authority in philosophy and destroy it. But that would be an incomprehensible move, for rational constraints cannot be authoritative ones.

The Magisterium can only exert authority as far as concerns the acceptance (and public profession) of contents, and so ask for faith or rejection. The demand is respectful of natural reason and of the autonomy of philosophy: assent on the basis of authority is faith. What is implied in such a conception is only that faith includes as part of its content that faith and reason cannot oppose themselves, and so that the Magisterium cannot teach something known as false on rational grounds, and that reason cannot establish something contrary to what the Magisterium teaches in matters of faith. It is a second-order thesis on the content of faith and the exercise of reason. And this is exactly Aquinas'conception [35]. What is affirmed here is 1) the uniqueness of truth, which can be reached by the way of faith or by the way of reason; 2) the truth of the content of faith; 3) the truth of what reason reaches when it reaches science; and 4) the ability of reason to reach science in those philosophical questions which are doubted by the agnostic christian philosopher.

The agnostic christian philosopher is not in a situation of contradiction, as long as he truly believes the teaching of FR and Aquinas on faith and reason. He only must admit or realize that he is able to go out of agnosticism, and that it would be very important to do so. Many agnostic christian philosophers are not really looking for rational grounds that would lead them out of agnosticism. They may think this is an impossible task, and so, according to the Magisterium, they must be wrong. They may think that, even if possible, this task is not the most urgent one. And they may be practically right or wrong, according to what they estimate more urgent. I suggest that the reason why they are not looking for those grounds is that they have no real hope to find them. That is why the main feature of the Encyclical is its parenetic discourse, encouraging philosophers to work in view of those truths.

And this leads us to my third and last question: what is the way out of philosophical agnosticism? I can make only a few remarfs. First, for the reasons just given, FR does not show the way out, though it emphasizes the second order thesis that there is such a way, and it encourages philosophers to find it. Second, the Encyclical does not trace the kind of philosophical achievement that could be considered as leading out of agnosticism. Of course, thomism is presented as such. But it is not said that thomism gives the good arguments, neither that good arguments must be such as those given by Aquinas. As we noted earlier, Aquinas's doctrine on faith and reason, a second order doctrine, is reassumed by John Paul II. But Aquinas's first order doctrines (e.g. his metaphyscics, and more specifically his proofs for God's existence) are not even alluded to. Acceptance, refusal or discussion of them are left to the autonomy of philosophy, as long as the content of faith is not compromised.

I would suggest the following as a radical modification of Aquinas'program which would still be in accordance with his second order views on faith and reason. According to aristotelian philosophy, a conclusive argument should have a syllogistical form, and be such that if the premises are true and the inference valid, science of the conclusion follows. For the sake of argument I go on restricting myself to the paradigm of the proofs for God's existence. If the inferences are valid and their premises true, so the conclusion is scientific. Few people have denied the logical soundness of the proofs, but many have contested one or more premises. I would insist on the conclusions. How can they be scientific and still denied by so many, even within the circle of the philosophers? This is not characteristic of science as we know it. We could evade this objection by saying that Aquinas's conception of science is not ours. But that would not be a good move, for I assume that in Aquinas's mind scientific demonstration is such that no one who grasps the premises and the logical links can still doubt the conclusion. However, forgetting those who absolutely deny the value of the proofs, I think that one can accept the premises, the logical soundness, and still have some doubts on the efficacy of the proofs.

This is to say that the "scientific" label seems to be too strong. Can we not see in the so-called demonstrations of God's existence, or of the intellect's subsistence, more inferences to the best explanation available (of movement, of order in nature, of existence of contingent things, and of human rationality as distinct from animal abilities), than deductive demonstrations, as Barabara-syllogisms are meant to be [36]. This would be more in accordance with a conception of philosophy as distinct from empirical, human and formal sciences, and, alone on its side, dedicated to the study of our natural beliefs and concepts, of their logical links, and of many philosophical erroneous interpretations of them. This would make philosophy as a descriptive discipline more than a demonstrative one, as having no particular thesis of its own, but as helping to maintain, against different speculative constructions, some of our basic natural convictions, including natural beliefs (in the exterior world or in God's existence, as in freedom or immortality), which can be found in different cultures.

I will not defend such a wittgensteinian, perhaps a thomistic- wittgensteinian, conception of philosophy. I would just suggest that such a deflationary approach could still satisfy the E's requirements. After all, to say that God's existence and human freedom and immortality can be reached by natural reason, is not to say that those truths, held by faith, are also deductively demonstrable. It could be sufficient to say that we have good reasons to accept them, that they are intrinsically intelligible, and give a good explanation or description of well known phenomena [37]. Another line of approach, and alteration of Aquinas's views, would be for example to say with many philosophers today, that the philosophical problem with God is less his existence than the intrinsic intelligibility of the attributes by which we describe him (omnipotence, omniscience, goodness, etc.). Aquinas affirms that before the study of God's attributes, we must establish his existence [38]. This is certainly too strong a requirement, inherited from the peripatetic tradition (Avicenna), which asks for the proof of the existence of the subject of science before investigating its nature. Can we not study God's attributes without any proof of his existence, but in order to show their intelligibility? Many atheologist arguments procede precisely by trying to show an inconsistency in one or more divine attributes. The refutation of atheologist arguments does not need to presuppose God's existence.

Those are, I think, amendments to Aquinas's conception of philosophical argumentation which are still in agreement with his views on faith and reason. I think they could also be maintained with many substantial theses of his philosophy and theology. But I also think that other aspects of his thought can no more be maintained. If I am right, this is a subject left to the philosophers discussions. FR assumes Aquinas's conception of the links between faith and reason, but leaves it to us to decide which philosophy will do the best job, while giving all Aquinas's work as an example. Speaking in a second order way of faith and reason, Aquinas has expressed the Magisterium's teaching, and no coherent christian philosopher could avoid it. But it is not the Magisterium's duty to tell which first order philosophical theses, which philosophy to choose, and it could not be its duty, for conceptual reasons: one does not choose his way in philosophy on the basis of authority (that would not be philosophy anymore), although one can be told to stop on this or that way, and obey; or to accept this or that content, and obey. In particular, it is left to the philosophers to decide whether thomistic metaphysics, and, more broadly, aristotelian philosophy, are still available, eventually with some alterations.

Should I add that this seems to me to be a great challenge?


[1] «It must not be forgotten that reason too needs to be sustained in all its searching by trusting dialogue and sincere friendship. A climate of suspicion and distrust, which can beset speculative research, ignores the teaching of the ancient philosophers who proposed friendship as one of the most appropriate contexts for sound philosophical enquiry.»

[2] De utilitate credendi , XII, 25 (quod intelligimus); Retractationes I, XIV, 25 (quod scimus).

[3] I know of only one occurence of Augustine’s formula, in Aquinas: Super Boetium De Trinitate , pr 3. But the link between faith and authority is made very often, and in augustinian words.

[4] De Praedestinatione sanctorum , II, 5

[5] Cogitare is the term used by Augustine whom Thomas follows in Quaest. de ver. , q.14, a.1; but, distinguishing cogitatio from scientia and from intellectus in Sum. theol. II-II, q.1, a.2, he defines it as a consideratio with inquisitio of the intellect. Consideratio is so a more neutral term, which may be used in defining science as well as belief, for example.

[6] The main references on which these divisions rely are In III Sent. , d.23, q.1, a.1-5; Quest. de ver. , q.14, a. 1-2; Super Boet. De Trin , q.3, a.1; Sum. theol ., II-II, q. 1-4; In Hebr. 11, 1.

[7] Thomas does not make any distinction between dissenting from p, and assenting to not-p.

[8] To my knowledge, the distinction between suspicio and opinio is made only in ST II-II, q.2, a.1

[9]. The firmness of assent distinguishes belief ( credere) from doubt, opinion and suspicion. The going on of cogitation ( cogitatio non formata ) distinguihes it from science, where cogitation stops and gives place to assent ( cogitatio formata ), and from intelligence, where assent arises without following any cogitation. In the Quaest de ver. , Thomas says that in credere, cogitation and assent are ex aequo , whereas in science, cogitation leads to assent through the way of resolution ( per viam resolutionis ).

[10] This the case in the Quaestiones de veritate , and in the Summa theologiae .

[11] Quaest. de ver. , q.14, a.2

[12] This in said in the commentary on the Hebrews Epistle, which is the latest text of the series. Thomas has progressively come to admit the unclarity of this definition, cf. C. Spicq, OP, «L'exégèse de Hebr., XI, 1, par s. Thomas d'Aquin», RSPT 31, 1947, 229-236.

[13] Super Boet. De Trin. , q. 3, a.1, ad 4.

[14] Sum. theol . II-II, q.1, a.7; and a.8

[15] Ibid. a.6 on the very notion of “article”, a.8 on their division.

[16] In Sum. theol I, q.1, a.8 he says of the Creed’s first article: «multa per fidem tenemus de deo quae naturali ratione investigare philosophi non potuerunt, puta circa providentiam eius et omnipotentiam, et quod ipse solus sit colendus. Quae omnia continentur sub articulo unitatis dei.»

[17] See Summa contra Gentiles I, 7.

[18] In I Sent. , prol., q.1, a.5; In III Sent. , d.24, a.3, qla 3; In Boeth. De Trin. , q.2, a.1; Sum. cont. gent. I, 8; Sum. theol., I, q.1, a.8; II-II, q.2, a.10; III, q.55, a.5, ad 3

[19] This is a main theme for the notion of theology as science, e. g. Sum. theol. I, q.1, a.2.

[20] Quodl. IV, q.9, a.3: «disputatio autem ad duplicem finem potest ordinari. quaedam enim disputatio ordinatur ad removendum dubitationem an ita sit; et in tali disputatione theologica maxime utendum est auctoritatibus, quas recipiunt illi cum quibus disputatur; puta, si cum iudaeis disputatur, oportet inducere auctoritates veteris testamenti: si cum manichaeis, qui vetus testamentum respuunt, oportet uti solum auctoritatibus novi testamenti: si autem cum schismaticis, qui recipiunt vetus et novum testamentum, non autem doctrinam sanctorum nostrorum, sicut sunt graeci, oportet cum eis disputare ex auctoritatibus novi vel veteris testamenti, et illorum doctorum quod ipsi recipiunt. Si autem nullam auctoritatem recipiunt, oportet ad eos convincendos, ad rationes naturales confugere. » (I have no english translation at my disposal)

[21] Ibid: Quaedam vero disputatio est magistralis in scholis non ad removendum errorem, sed ad instruendum auditores ut inducantur ad intellectum veritatis quam intendit: et tunc oportet rationibus inniti investigantibus veritatis radicem, et facientibus scire quomodo sit verum quod dicitur: alioquin si nudis auctoritatibus magister quaestionem determinet, certificabitur quidem auditor quod ita est, sed nihil scientiae vel intellectus acquiret et vacuus abscedet.

[22] This is the incipit in many traditions of the text, the title “Summa contra gentiles” comes from some explicit. See Gauthier in Saint Thomas d’Aquin, Somme contre les Gentils , Introduction, Editions Universitaires, Paris, 1992, 109-112.

[23] I have tried to do it in my introduction to Thomas d’Aquin, Somme contre les Gentils , I, Dieu, GF Flammarion, Paris, 1999, 27-33.

[24] II, 46 says that it was convenient for the perfection of the universe that some intellectual creatures existed, but ch. 91 is more affirmative in asserting that there must exist intellectual creatures separated from all bodies.

[25] Cf. III, 134-138.

[26] See the prologue.

[27] Thomas’s evolution is mainly relative to his better knowledge of Aristotle’s Ethics in the ST, and so to a more philosophical approach of moral life

[28] The notion of praeambula fidei , not frequent in Aquinas, appears in the Commentary on Boethius’s De Trinitate q.2, a.3: sic ergo in sacra doctrina philosophia possumus tripliciter uti. Primo ad demonstrandum ea quae sunt praeambula fidei, quae necesse est in fide scire, ut ea quae naturalibus rationibus de deo probantur, ut deum esse, deum esse unum et alia huiusmodi vel de deo vel de creaturis in philosophia probata, quae fides supponit.

In the ST, II-II, q.2, a.1, ad2, he says: rationes demonstrativae inductae ad ea quae sunt fidei, praeambula tamen ad articulos, etsi diminuant rationem fidei, quia faciunt esse apparens id quod proponitur; non tamen diminuunt rationem caritatis, per quam voluntas est prompta ad ea credendum etiam si non apparerent. Et ideo non diminuitur ratio meriti.

[29] See for example this threefold division in CG IV, 1.

[30] In the text of the Super Boetium quoted earlier, Thomas distinguishes three uses of philosophy in theology, but the third one is that of refutation, it is not a strategy of its own, but it goes with the two others. The text goes on that way: (Possumus philosophia uti) Secundo ad notificandum per aliquas similitudines ea quae sunt fidei, sicut augustinus in libro de trinitate utitur multis similitudinibus ex doctrinis philosophicis sumptis ad manifestandum trinitatem. Tertio ad resistendum his quae contra fidem dicuntur sive ostendendo ea esse falsa sive ostendendo ea non esse necessaria)

[31] There are at least 22 mentions of “metaphysics” (in a substantive or adjective form) in the Encyclical, 9 of which appear in the n.83. Sometimes “metaphysical” characterize one aspect or one domain of reality, or one kind of knowledge, or power to know, unrestricted to the empirical (n.22; n.72: metaphysics in Indian conceptions of reality; n.105: the metaphysical dimension of truth), and more often, the philosophical discipline called “metaphysics” (n.55: the so-called “end of metaphysics”; and nn.61; 72; 83; 88; 95; 97; 98; 106)

[32] In n.13 Aquinas is quoted, from the Sequence for the Solemnity of the Body and Blood of the Lord. In n.74, he is listed among other medieval doctors.

[33] The three following features of philosophy, mentionned in different places in the Encyclical, are grouped to constitute the three postulata formulated by the Pope at the end, nn.81-83.

[34] Autonomy is also a very often used expression in FR. I have numbered 17 occurrences, almost all of them in a positive sense: autonomy is characterized as legitime (nn.80 and 98 are exceptions, but they criticize a bad use of autonomy more thant autonomy itself). Autonomy is applied to reason (n.16; 67; 79), philosophy (n.45; 48; 49; 75; 85; 108), science (n.45, 106), theology (n. 75), faith (n.48), and to the creature (n.15). The principles of autonomy charactristic of modern thought are mentioned n.77, in order to explain why the expression “ancilla theologiae” would not be well received.

[35] As given in the CG I, 3-8, for example.

[36] R. Swinburne has often defended this line of argument.

[37] It does not seem to me that what the Catechism says on man as capax Dei , in its frist chapter, asks for more thant that.

[38] For example, in the CG I, 9, §5