St. Thomas on Reason and Knowledge of Truth

Last week I felt compelled to clarify what exactly St. Thomas believed about the place of reason in apologetics. This was in response to a post by TF. In that post, TF attempted to defend a form of apologetics that seems to prefer the appeal to Scripture as a justification for a Christian's claims, as opposed to making an argument that is justified on terms that the non-Christian accepts. (If that is a loaded summary, it's merely for the sake of cutting to the chase). I demonstrated that such an apologetic is thoroughly alien to the thought of Aquinas, who wrote a five-volume apologetic (the Summa Contra Gentiles) whose operating principle is that "we must, therefore, have recourse to the natural reason, to which all men are forced to give their assent" when attempting to persuade those who do not accept the authority of Scripture, Tradition, or the Church (SCG, I, 2, 3).

This evening I came across a passage in the Summa Theologica demonstrating the point that such an approach is not at all doomed to failure.

Augustine says (Retract. i, 4): "I do not approve having said in the prayer, O God, Who dost wish the sinless alone to know the truth; for it may be answered that many who are not sinless know many truths." Now man is cleansed from sin by grace, according to Psalm 50:12: "Create a clean heart in me, O God, and renew a right spirit within my bowels." Therefore without grace man of himself can know truth.

I answer that, To know truth is a use or act of intellectual light, since, according to the Apostle (Ephesians 5:13): "All that is made manifest is light." Now every use implies movement, taking movement broadly, so as to call thinking and willing movements, as is clear from the Philosopher (De Anima iii, 4). Now in corporeal things we see that for movement there is required not merely the form which is the principle of the movement or action, but there is also required the motion of the first mover. Now the first mover in the order of corporeal things is the heavenly body. Hence no matter how perfectly fire has heat, it would not bring about alteration, except by the motion of the heavenly body. But it is clear that as all corporeal movements are reduced to the motion of the heavenly body as to the first corporeal mover, so all movements, both corporeal and spiritual, are reduced to the simple First Mover, Who is God. And hence no matter how perfect a corporeal or spiritual nature is supposed to be, it cannot proceed to its act unless it be moved by God; but this motion is according to the plan of His providence, and not by necessity of nature, as the motion of the heavenly body. Now not only is every motion from God as from the First Mover, but all formal perfection is from Him as from the First Act. And thus the act of the intellect or of any created being whatsoever depends upon God in two ways: first, inasmuch as it is from Him that it has the form whereby it acts; secondly, inasmuch as it is moved by Him to act.

Now every form bestowed on created things by God has power for a determined act, which it can bring about in proportion to its own proper endowment; and beyond which it is powerless, except by a superadded form, as water can only heat when heated by the fire. And thus the human understanding has a form, viz. intelligible light, which of itself is sufficient for knowing certain intelligible things, viz. those we can come to know through the senses. Higher intelligible things the human intellect cannot know, unless it be perfected by a stronger light, viz. the light of faith or prophecy which is called the "light of grace," inasmuch as it is added to nature.

Hence we must say that for the knowledge of any truth whatsoever man needs Divine help, that the intellect may be moved by God to its act. But he does not need a new light added to his natural light, in order to know the truth in all things, but only in some that surpass his natural knowledge. And yet at times God miraculously instructs some by His grace in things that can be known by natural reason, even as He sometimes brings about miraculously what nature can do. [ST I-II, Q109, A1; emphasis added]

So we see that St. Thomas teaches the natural gifts God has given us - namely, reason and the senses - are sufficient for us to acquire knowledge (that is to say, we may learn truth), with the major exception of those things which can only be known by the grace of faith. Of course, it is another question entirely what extent of knowledge is available to us by natural means; St. Thomas provides us some "small" (!) idea of his judgment thereof in the SCG.

Clarification concerning St. Thomas and the place of reason in apologetics

Recently TF was involved in a relatively lengthy (in words, if not time) debate/discussion with some of his co-religionists concerning apologetics and epistemology. This evening he has followed up with a new post in which he attempts to defend his view from Scripture and history. I'm not so much interested in the defense as such, nor in the particulars of whatever his view might be, as in the use he attempts to make of St. Thomas in defense of it. It seems to me that he has only got half the story.

He quotes two articles: II-II Q4 A8 ("Whether faith is more certain than science and the other intellectual virtues?") and II-II Q8 A5 ("Whether the gift of understanding is found also in those who have not sanctifying grace?"). Aquinas' answer to the first is "Yes, it is," and to the second he replies that they do not.

The problem, as I see it, is that there was a particularly apologetic bent to the discussion in which TF had previously participated, and the passages from the Summa that he quotes are not directed towards the question of apologetics. He summarizes this new post this way:

[T]ools like the Transcendental Argument for the existence of God (TAG) can be a useful negative took to expose presuppositions, but it cannot be a complete defense of the faith - it cannot be a stand-alone apologetic. Human reason must be subordinated to divine truth, even though human reason is an instrument and tool by which and through which we understand.

Well, the problem is that the average unbeliever can hardly be expected to agree that he must subordinate his reason to the Bible. And St. Thomas recognizes this.

For example, when discussing whether the Holy Trinity can be known by natural reason, St. Thomas answers in the negative:

It is impossible to attain to the knowledge of the Trinity by natural reason. For, as above explained (12, 4, 12), man cannot obtain the knowledge of God by natural reason except from creatures. Now creatures lead us to the knowledge of God, as effects do to their cause. Accordingly, by natural reason we can know of God that only which of necessity belongs to Him as the principle of things, and we have cited this fundamental principle in treating of God as above (Question 12, Article 12). Now, the creative power of God is common to the whole Trinity; and hence it belongs to the unity of the essence, and not to the distinction of the persons. Therefore, by natural reason we can know what belongs to the unity of the essence, but not what belongs to the distinction of the persons. [I Q32 A1]

This is presumably non-controversial - at least to some extent. But St. Thomas continues:

Whoever, then, tries to prove the trinity of persons by natural reason, derogates from faith in two ways.

Firstly, as regards the dignity of faith itself, which consists in its being concerned with invisible things, that exceed human reason; wherefore the Apostle says that "faith is of things that appear not" (Hebrews 11:1), and the same Apostle says also, "We speak wisdom among the perfect, but not the wisdom of this world, nor of the princes of this world; but we speak the wisdom of God in a mystery which is hidden" (1 Corinthians 2:6-7).

More importantly in the present context, though, is the second way:

Secondly, as regards the utility of drawing others to the faith. For when anyone in the endeavor to prove the faith brings forward reasons which are not cogent, he falls under the ridicule of the unbelievers: since they suppose that we stand upon such reasons, and that we believe on such grounds.

Therefore, we must not attempt to prove what is of faith, except by authority alone, to those who receive the authority; while as regards others it suffices to prove that what faith teaches is not impossible. Hence it is said by Dionysius (Div. Nom. ii): "Whoever wholly resists the word, is far off from our philosophy; whereas if he regards the truth of the word"--i.e. "the sacred word, we too follow this rule." [emphasis added]

Now unbelievers do not receive the authority of Scripture; hence, St. Thomas says, one opens himself to ridicule if he appeals to the Bible in defense of that which can only be known by faith when attempting to persuade unbelievers concerning the Faith. And this is not the only place in the Summa Theologica where he makes this argument; he says much the same thing, for example, in I Q46 A2 in discussing the question of whether the creation of the world can be proven by reason or must be accepted as an article of faith:

By faith alone do we hold, and by no demonstration can it be proved, that the world did not always exist, as was said above of the mystery of the Trinity (32, 1). The reason of this is that the newness of the world cannot be demonstrated on the part of the world itself. For the principle of demonstration is the essence of a thing. Now everything according to its species is abstracted from "here" and "now"; whence it is said that universals are everywhere and always. Hence it cannot be demonstrated that man, or heaven, or a stone were not always. Likewise neither can it be demonstrated on the part of the efficient cause, which acts by will. For the will of God cannot be investigated by reason, except as regards those things which God must will of necessity; and what He wills about creatures is not among these, as was said above (Question 19, Article 3). But the divine will can be manifested by revelation, on which faith rests. Hence that the world began to exist is an object of faith, but not of demonstration or science. And it is useful to consider this, lest anyone, presuming to demonstrate what is of faith, should bring forward reasons that are not cogent, so as to give occasion to unbelievers to laugh, thinking that on such grounds we believe things that are of faith. [emphasis added]

And again in II-II, Q1 A5 ad 1:

Unbelievers are in ignorance of things that are of faith, for neither do they see or know them in themselves, nor do they know them to be credible.

But if they do not consider the Bible to be credible as the Word of God, then it is pointless to attempt to persuade them on the basis of its authority.

But all of this is mere window dressing compared to the major argument: that is, the Summa Contra Gentiles! The entire work is intended as an argument for the Faith not from Scripture, but rather on the grounds of reason:

[2] And so, in the name of the divine Mercy, I have the confidence to embark upon the work of a wise man, even though this may surpass my powers, and I have set myself the task of making known, as far as my limited powers will allow, the truth that the Catholic faith professes, and of setting aside the errors that are opposed to it. To use the words of Hilary: “I am aware that I owe this to God as the chief duty of my life, that my every word and sense may speak of Him” [De Trinitate I, 37].

[3] To proceed against individual errors, however, is a difficult business, and this for two reasons. In the first place, it is difficult because the sacrilegious remarks of individual men who have erred are not so well known to us so that we may use what they say as the basis of proceeding to a refutation of their errors. This is, indeed, the method that the ancient Doctors of the Church used in the refutation of the errors of the Gentiles. For they could know the positions taken by the Gentiles since they themselves had been Gentiles, or at least had lived among the Gentiles and had been instructed in their teaching. In the second place, it is difficult because some of them, such as the Mohammedans and the pagans, do not agree with us in accepting the authority of any Scripture, by which they may be convinced of their error. Thus, against the Jews we are able to argue by means of the Old Testament, while against heretics we are able to argue by means of the New Testament. But the Muslims and the pagans accept neither the one nor the other. We must, therefore, have recourse to the natural reason, to which all men are forced to give their assent. However, it is true, in divine matters the natural reason has its failings. [I, 2, 2-3; emphasis added. Note that I quote from the Pegis translation, which (as far as I know) is not legally available online; the link here is to another translation]

So we see that St. Thomas acknowledges the weakness of reason for some things, but he insists that with unbelievers there is no other course that can be taken. Far from making his appeal from Scripture to the unbeliever, he argues on grounds that the unbeliever can accept. Hence we see that TF hasn't told the whole story about how Aquinas views the utility of Scripture for persuading the non-Christian.

Update: I realize that TF concedes:

It is not that there is no reason to believe, but that some things cannot be reached by bare reason.

Again, as I said at the outset, the particulars of his view aren't what concerns me here. When it comes to Aquinas' view of the role of reason in apologetics, TF's post doesn't give the whole picture. Appeals to authority are fine when we speak to those who accept the authority, but they're meaningless to those who don't.

The Holy Trinity and Human Nature

A couple days ago I mentioned an upcoming post concerning dogma and how we think about other things. I think this is an interesting example of what I was talking about in that post.

Pelikan writes (p. 72):

This clarification and expansion of Chalcedon in the direction of teaching two wills and two actions ... took its start from the doctrine of the Trinity, clarifying its christological terminology on the basis of trinitarian usage. In the Trinity there were three hypostases, but only one divine nature; otherwise there would be three gods. There was also a single will and a single action. Thus will was an attribute of a nature and not of a hypostasis, natural and not hypostatic. Hence the person of Christ, with a single hypostasis and two natures, had to have two wills, one for each nature. [emphasis added]

Although it might seem to us - if we think carelessly about the question and ignore the implications of christology described by Pelikan - that a will is something I have by virtue of being a person - an individual hypostasis - we see that the consequences of such thinking fall afoul of what is actually true. In the case of Christ, it would mean that - since he was a divine person with two natures - he had a single will (the divine one); or, if that were to be unacceptable to us, we might go the Nestorian route and insist that in Christ a divine and human person - two hypostases - were united, because Christ clearly had a human will.

But both of these conclusions are false. So we see that what we believe about God and Christ has profound implications for what we believe about ourselves. Likewise what we believe about ourselves may affect how we think about the Incarnation and the Godhead. It is important that we get the feedback cycle right here. Dogmas about the Incarnation and the Godhead are absolutely true because they are divinely revealed. We reject them at our peril. Given a conflict between dogma and our own ideas, we necessarily must conclude that it is our ideas that are wrong rather than the reverse.

Obviously it is not easy sometimes for us to reach that conclusion. On such occasions, we must take refuge in the virtue of humility.

A Real Discussion-Killer

I read something today that I found to be a little surprising. I will refrain from identifying the author, because it's possible that I might be misunderstanding him. Even if I have, though, I think that the words as I interpret them are probably representative of enough people that it doesn't really matter who said them.

[Absolute certainty about things we say that we "know"] is only attainable through revelation.

I paraphrased the portion in brackets because there was some ambiguity in the source, which read more like, "To have knowledge is to know with absolute certainty."

Heh. That ("knowledge is knowing with certainty") reminds me of an old B.C. cartoon in which one of the characters opens Wiley's Dictionary and looks up the word "pollution." The definition: "The result of polluting." So he turns to the definition of "polluting" and reads there: "to pollute". So he turns to the definition of "pollute" and reads: "to cause pollution." At that point he sets fire to the dictionary, which belches forth a polluting smoke cloud. :-) Of course the point is that if a definition is self-referential, it's pretty hard to get out of the circle.

Maybe this is not an entirely fair way to characterize that definition of "knowledge," but it seems pretty hard to avoid. On the other hand, I suppose it's probably difficult to talk about "knowing" without becoming self-referential at times, so I'm not going to hold anyone's feet to the fire about that. Suffice it to say, though, that this is one source of my uncertainty about whether I've understood the author. :-) Maybe a better way of expressing the thought would be by way of contrast: it's not actual knowledge if you do not possess absolute certainty about it. Hence a property of knowledge is that the one who possesses it has absolute certainty about the subject of his knowledge.

[By the way, Aristotle characterized "knowledge" in pretty much the same way - namely, that one of its properties is that it is certain. He said that a lot of what people say they know really doesn't amount to much more than opinion. He didn't say that this knowledge came by way of revelation, though. But I digress.]

Our author says that "knowledge" defined like this can only be had "through revelation." There is a little fuzziness here, too. Does he mean that absolute certainty is available only "through" the Bible, or "through" direct revelation from God? Let's consider each possibility. If he means that we can obtain absolute certainty only through the Bible, then it seems to me that what he has said is unintelligible. If he really means that, then by the very nature of the case sensory perceptions are ruled out as a source of absolute certainty, and if that is so, then how will we get absolute certainty from the Bible? We must make use of our senses in some way in order to read or hear or touch (e.g., through Braille) Scripture; if we cannot have absolute certainty from what our senses tell us, then it is likewise impossible for us to have it about what we read or hear or touch in the Bible. The consequence of that, of course, is that absolute certainty would be absolutely impossible; hence the definition would leave us with no hope for any absolute certainty whatsoever.

If that's the case, then there really isn't a point in debating much of anything, is there? Everyone's opinion is as good as anyone else's, and those who claim otherwise would be blowing smoke in your eyes. Consequently it seems to me that this view is a real discussion-killer.

The second alternative is that he means we can only have absolute certainty by way of direct divine revelation. Now I certainly agree that this is a way of obtaining certainty, on a Christian understanding of things; but it should also be said that there are some silent assumptions about God here (and really, the same assumptions must be in force if we get certainty from the Bible, too): namely, that there is only one God, and that he is perfectly good and truthful (so that no evil god could tell us lies by means of direct revelation). Hopefully you see the obvious questions here:

Where do we get these ideas about God? How do we know (with absolute certainty) that God is trustworthy?

Hopefully it will be obvious that these are not idle questions for the man who insists that we can obtain certainty only through revelation (whether directly or through Scripture). He needs to have some reason to know that God is trustworthy, but on his own terms he has none, it seems to me.

Hopefully it will be equally obvious that I do not subscribe to this view of the question, although I suppose I probably held to something like it when I was a Protestant. I think that in fact we can have certainty about at least some things, and possibly even many things. A good example is the law of non-contradiction. A given thing 'A' cannot be 'X' and 'not-X' at the same time and in the same respect. We can know this with certainty. It is a logical impossibility. And speaking of logic, we can also know with absolute certainty the conclusion of a syllogism. If all men are mortal and Socrates is a man, then Socrates is mortal. Given the truth of the premises, the conclusion is likewise certain to be true.

This sort of knowledge doesn't come to us by way of revelation; it comes to us by way of reason. And so we can jump to the sed contra: We do not obtain absolute certainty solely by way of revelation, but also by means of reason. We can know, for example, that God is perfectly good (and consequently truthful); and because we can know this, we can trust his revelation to be absolutely truthful as well.

(that's a ridiculously brief summary of something that St. Thomas spends pages and pages discussing, both in the Summa Theologica and in the Summa Contra Gentiles)

This does not mean that reason is omnicompetent. We cannot deduce literally everything. But we can obtain certainty about many things by way of reason, and we would be foolish to suppose otherwise.

We can also obtain certainty by way of our senses. I know for certain that there is a keyboard in front of me, and that I am using it to type this sentence. Some folks are prone to say that our senses are not reliable, but I submit that these people do not spend much time fretting over whether the substance on their dinner plate is steak or grass clippings. If they were serious about their uncertainty, they certainly (!) would be worrying about that meal. :-) And how will they get that certainty out of the Bible if he can't trust his senses?

A few observations about St. Anselm's Ontological Argument

Many, many years ago I read Sproul, Gerstner, & Lindsley's book Classical Apologetics. This fact is etched upon my brain. I no longer have the book, so I may be a bit off on the pagination here, but I spent something like a week or two trying to understand pp. 92-103. The subject was St. Anselm's ontological argument, and I just couldn't get it in the way that it was being presented by the authors. Some important things happened in my educational growth as a result.

Probably the most significant was that I found myself asking the question, "What if the problem isn't with me? What if this is incomprehensible...because it is incomprehensible?" It turns out in retrospect that my objection was really about 700 years old, because St. Thomas had already been there: having an idea of a thing in my mind doesn't imply anything about whether that thing actually exists outside of my mind. Consequently there doesn't seem to be any useful apologetic force to the argument.

(As an aside, I'm still pretty shocked that Sproul seriously thought it could be useful in proving God's existence to the unbeliever. I recall that he denied it was legerdemain or smoke and mirrors, but I couldn't see any way to clear the air and get out of the funhouse.)

I'm not a philosopher by training, but it seems to this armchair analyst (perhaps after having read Knowles) that St. Anselm's argument hinges upon a view of creation with Platonist hues. The whole thing might make more sense if we were to concede the notion of innate ideas: if the ideas in our brains had some original, external existence apart from us, then it might make more sense to talk about a necessary Being who must exist if I can conceive of Him.

Knowles has some useful things to say about the argument in pp. 102-106 of The Evolution of Medieval Thought (heh. It's amusing that he too can't avoid the rhetoric of magic when discussing it: "[M]any will have an uneasy feeling that a logical sleight of hand has been brought off at their expense." p. 103). One particularly interesting thing is that

Anselm himself specifically, and in the same context [of defending the argument], recognized the difference between a mental and a real existence.

Realization of this has led some to maintain that the argument is not a merely logical one - the analysis of a concept - but an epistemological one. It is said that Anselm held so firmly the Platonic realism, according to which the idea is the only reality directly cognisable by the mind, that for him the presence of the idea of God in the mind implied the existence of the subsistent idea of God - that is, of God Himself, since there is no distinction of any kind in God. [p. 104; emphasis added]

Aha! Well, that might explain the whole thing a bit better, even if I don't agree with the saint about Platonic realism. I'd much rather that the nature of the disagreement be one of such substance as this than be forced to wonder whether Anselm was a poor logician.

Knowles proceeds to discuss other possible resolutions to the question, including Gilson's.

Anselm, he points out quite rightly, held that the mind could arrive at truth, which was the adequacy of the mental concept to express the being external to the mind. In other words, the external being is the cause of the concept and its truth, not vice versa. If therefore a being is not only existent, but necessarily so (as is God by definition), and is in fact the only being necessarily existent ('than which no greater can be conceived') then the only true concept of this Being will be one that agrees with its definition, and the mind will recognize the adequacy of the concept and the necessity of the existence of its object as soon as it as been presented to the mind. [p. 105; no reference to where in Gilson's work this hypothesis is presented]

This seems to maybe put a Thomistic-ish spin on things, and I'm not really sure that it is as satisfactory as the prior one I discussed. Certainly I don't think that on Gilson's reckoning Anselm's argument has any useful force with non-Christians. Knowles goes on (ibid) to say that it was not really intended for that purpose, though.

Interestingly, he also says that "Bonaventure and the Augustinians in general accepted it, as strengthened by the doctrine of the divine illumination of the intellect, while Aquinas and the Aristotelians rejected it...Ever since, indeed, it has been a touchstone of Realism, and as such accepted in one form or another by Descartes, Leibniz and Hegel, and rejected by Locke, Kant, and Thomists of every kind" (ibid).

This suggests to me that locating the difficulties about the argument for me in the fact that I'm much more inclined towards Thomism than towards Platonic realism is the Right Thing to Do. It's unlikely that I'll be the one to find out by researching the question, but it would be interesting to know if Sproul is more Platonist than Aristotelian in his epistemology. Given his enthusiasm for Anselm's argument, I suspect that he is.

The Importance of Humility

There are many truths that may be discovered by the use of reason alone. There are others that may be known only by faith. When it comes to truths we know by way of reason, it is extremely important that we remember what St. Thomas has said about this - namely, that it is difficult to arrive at truth by way of reason. Given this fact, and given that we are limited both in our gifts and resources, it is wise for us to bear in mind the words of Sirach:

Do not try to understand things that are too difficult for you, or try to discover what is beyond your powers. Concentrate on what has been assigned you, you have no need to worry over mysteries. Do not meddle with matters that are beyond you; what you have been taught already exceeds the scope of the human mind. For many have been misled by their own presumption, and wrong-headed opinions have warped their ideas. [Ecclus. 3:21-26, JB]

St. Thomas, pray for us that we may be humble, understanding our own frailties as we seek to understand what we may, remaining steadfast at all times in the Faith of the Church.

Knowles - Augustine's Epistemology

Warning - I'm by no means equipped to write very much about this subject; this post will be for the most part merely a reference for a few notes about it.

David Knowles devotes a chapter to St. Augustine in his book The Evolution of Medieval Thought (as an aside, there are some preposterous prices for this book on Amazon; I paid seventy-five cents for a copy in average condition, but some folks are apparently asking as much as $240.00 for it! I'm obviously in the wrong business - or maybe those sellers are :-) It's a great book - but there is no way I'd pay $240 for it). He doesn't do this because he considers Augustine a medieval author; rather, he does so because of Augustine's tremendous influence on medieval thought.

Knowles explains that St. Augustine's epistemology is a difficult subject, owing partly to the fact that he knew very little of Plato's writing and none of Aristotle's (p. 40). He seems to have been influenced more by Plotinus: "There is a practical rule which rarely fails the commentator on Augustine's philosophy: it is that when a source for his thought is wanting the Enneads of Plotinus should be searched" (p. 43).

Knowles writes that (although Augustine is not terribly consistent about it) for the most part the saint viewed cognition as driven primarily by divine illumination of the intellect (p. 40f). For Augustine "all perception and knowledge arises within the soul; the soul is not acted upon directly by the external world, nor does it 'abstract' anything from that world in the process of cognition" (ibid).

Knowles remarks that there is sharp disagreement among scholars about St. Augustine's epistemology, and since I can barely wrap my head around it, I'm going to leave it at that for now.