Probable Certainty, Pt. 2 (by Ambroise Gardeil, O.P.)

Brief Translator’s Remarks

This article closes out the discussion of probable certainty written by Fr. Ambroise Gardeil. In the background of his discussion, especially given his careful analysis of the role of volitional fear in opinion, the reader will sense the debates over probabilism. Fr. Gardeil wishes to show clearly that while volitional fear can express itself as a property (but not of the essence) of opinion, this does not imply that opinion’s probable certainty also involves assent to the “feared other side / position.” He has a significant concern with the probabilist logic that would detach probable certainty from the overall élan toward the truth, as though probable certainty were, in fact, like a doubt (where one does not assent to either side but, instead, is in fear regarding the truth of both sides). Thus, one would gather a host of supposedly “probable” positions—but such pseudo-probability would not rise above a kind of general possibility, a list of options that were not totally ridiculous, though none of them would be predominantly true. Against this modern sense of “probability,” one understands, therefore, why in the previous article he is clear, the true and distinct noetic state that is “probability” is characterized by “probabiliority,” that is, the fact that what is assented to is more probable. (The informed reader also will note some implications here regarding classical Dominican positions during the probabilist debates.)

Also in the background, though less marked, are his concerns regarding the role of opinion in the assent of credibility, something he discusses more in his Crédibilité et apologétique. On this latter point, contemporary theology could no doubt benefit from a rapprochement (which Gardeil himself indicates in the first article) between the psychological researches in St. John Henry Newman’s Grammar of Assent and the philosophically solid teaching provided by Gardeil here, based not only on the Topics of Aristotle but also on later Scholastic logical developments (especially Thomas Aquinas, Albert the Great, and Domingo de Soto) and the teaching of the First Vatican Council. (I would note, also, the synthesis of certain points in Gardeil found in Garrigou-Lagrange, though the latter very much wishes to insist upon the certitude of credibility, in line with Dei Filius’s own assertions.)

As a kind of summary of the overall implications of Gardeil’s work in these articles, I will note the following points of contact that can be deepened by taking into account his work and deepening it:

• A fuller Thomistic account of dialectical reasoning (Topics)

• A fuller Thomistic account of rhetorical reasoning, given that contingency plays a special role there as well. Gardeil here limits himself to dialectics. At times, though, one notes that the volitional property of probable certainty implies important points vis-à-vis rhetorical reasoning (both as regards moral matters but as an adjunct to the instruction of scientific knowledge, etc.)

• A fuller Thomistic account of the way that scientific habitus (pl.) deploy opining in their discovery of truth. Also, a close study of the way that an utterly certain opinion is the final disposition for a scientific conclusion.

• As a point of general methodology, a consideration of Gardeil’s criticism of the modern notion of probability (especially when applied alongside the scholastic notion of science) would likely buttress the claim that Fr. Cuddy has made elsewhere, namely that the methods of theology (and I would also say of a certain kind of Catholic philosophy too) are a kind of dogmatic application of the old probabilism. What is needed, rather, is a full doctrine of De locis theologicis and, perhaps too, De locis philosophicis, although the latter will be quite different from the former. Nonetheless, the development of sciences requires an account of the methodology to be deployed in using sources in service of the truth of the particular discipline. I agree, in fact, with much of Gilson’s claims about the importance of historical methods in philosophical research. But, I am also fearful of a kind of pan-source fixation that transmutes philosophy and theology into a love of philosophers (and not wisdom) and a “theologianology,” as Fr. Cuddy has so well stated.

• The psychology of the emotions deals much with probable certainty. Discussing the distinction between mere active imagination and opining seems like a likely source of interesting insights.

• A deeper Thomistic account of the cognition of historical facts will doubtlessly and clearly benefit from a more expansive treatment of probable certainty.

• Any account of social life must account for the important role played by probable certainty. It is the social glue of day to day life, and it also plays a pivotal role regarding how we understand the importance of competence in social life.

• Although Gardeil only hints at it a bit here, the cogitative power has a particularly important role to play in many matters related to probable certainty.

• Any future revisiting of moral casuistry (which is likely necessary) will need, nonetheless, to take into account analyses such as these (as well, obviously, as I have argued many times elsewhere, the virtue of prudence with all of its various annexed virtues.)

• As Gardeil himself notes, this work allows for certain logical rapprochements with (and nuances / corrections to) Newman’s more psychological work in Grammar of Assent

A full PDF of the complete Gardeil text (all three parts) is available by clicking here.

III. Opinion-Assent

Having set forth the definition, subject, causes or “causative factors,” and properties of the probable, we must now study the subjective reaction of the intellect under its influence. This is what we will call Opinion-Assent.

In harmony with the previous section’s divisions—and for the same reasons—we here divide the study of Opinion-Assent into three parts:

1˚ Definition of Opinion.

2˚ Its subject and subjective causes or “causative factors”

3˚ Its property: formido errandi, fear of error.

1. Definition of Opinion.

Opinion is commonly regarded as being the act by which the mind corresponds to the appearance of a given probability within the field of one’s knowledge. This correspondence between probability and opinion is so generally accepted that we often mistake one for the other: we say, “an opinion” in order to thereby designate the object of the opinion, namely, a probable statement. This is a specific case of the general law of transposition that governs the relationship between faculties and their proper objects. Thus, for example, we say “faith” to signify the content of the object of fait and “science” to designate the object of the intellectual virtue of science. This sort of solidarity thus testifies that the probable is the proper object of opinion. The real definition of opinion, or at least its formal element, immediately follows from such customary speech: opinion has the probable as its proper object.

But how does opinion envision this object? Does it do so through an act of intuition, a simple gaze by the mind, or rather, by an act of judgment? The probable must itself tell us how it wishes to be considered. Opinion, as the mental aftereffect of the appearance of the probable, must reflect, in the form of a subjective attitude, the modalities of its objective mover. The law of parallelism between action and passion demands it.¹

Now, as we saw earlier, the probable presents itself concretely as a proposition, as a statement involving a connection between two terms. The subjective reaction required by such an object can only be a judgment. If the mind were content to see by immediate intuition [i.e., through the first operation of the intellect] the terms present to it, the mind would meet the demands of its object. It must in turn, and subjectively, join together what must be joined together and separate what must be separated. Any objective composition or division of terms is truth in potency, postulating its actualization in and through a formal judgment by the mind. It is up to the mind to declare that the composition or division true or false, which is called judging. Opinion is therefore a judgment.²

Let us push even further the regressive method from subject to object, which is our guiding thread, a step further.³ And let us delve into the intimate characteristics of opinion, taking as our guiding light the characteristics of the objective probable under which opinion is actualized.

As we saw earlier, a probable statement involves two elements that appear to be in conflict, though they are intimately fused together within it. This state of internal distension is characteristic of the probable: on the one hand, the probable statement has a positive, accentuated truth value. It is a likely statement [vraisemblable],⁴ i.e. close to the full truth. On the other hand, it is contingent, containing some kind of possibility that it may be false.

Let us trace out how these two objective modalities reverberate within the act of the subject who stives to intellectually assimilate the probable.

I. The influence of verisimilitude of the probable on opinion. The positive truth value that the probable claims for itself is matched by the mind’s adherence and assent. The mind has only one law: to equal itself to reality, to truth. When the truth passes within its reach, “Adsum,” it answers “Here I am!” Now, there is truth in the probable. There’s a truth that comes from its important ties to reality, a truth that, at the moment of its contact with the mind, has left far behind the false verisimilitude and improbability of the less probable. The contest—if it ever took place—is over. The preponderance has been asserted. And, on the dialectical battlefield, all that remains is that which is like unto the true. How can the mind fail to give it a positive assent—measured by the preponderance of its objective truth? Here too, the law of equal action and reaction must run its course. Opinion is therefore an assent, a positive affirmation.

I do not wish to return to topic concerning the lamentable confusion that has allowed some minds think that an opinion is something ultimately akin to doubt. I stressed this point sufficiently in the previous section.⁵—It is, nonetheless, useful to mark out (from the perspective of the subject, and not, as in our earlier discussions, from that of the object⁶) the reason why we wish to separate ourselves from these baleful theories of pseudo-probabilism.

Instead of considering the probable within the very reality of the life of the mind, it has been conceived in terms of an ideal, abstract mind. Real intelligence is essentially a living order to What Is, to the absolute truth. This has been overlooked [by those who enter the field of probabilist calculations]. The mind has been transmuted into a recorder of probabilities, something like the referee at a sports match, noting the blows struck by contradictory abstract probabilities and awarding points with benevolent impartiality.

This was, no more, no less, to forget the gravitational pull of this sanctuary, the immanent finality of intellectual labor. Indeed, what counts for a mind ordered to absolute truth is not what is probable for such and such a reason, under such and such an aspect, relative to such and such another likeness. The road to error—the hell of the mind—is paved with such relative probabilities. The probability that counts is the one that appeals on behalf of its relation to absolute truth. And it is obvious why this is the case: the mind seeks that which is, purely and simply. Only probability concerning what is, concerning the absolute truth, is entitled to its consideration. Everything else is a mere curiosity for it, a chance occurrence that has nothing to tempt the objectivity of its habits. Now, the probability of the absolute truth is necessarily unique: it is what clenches hold to the truth as close as possible; in scholastic terminology, it is the ultimate preparatory disposition for the indivisible form that is truth. Consequently, a mind that is essentially passive towards absolute truth, as ours is, is necessarily impressed by probability; it leans towards it with all the weight of its own ordering to absolute truth, which attracts it in and through probability, its reflection and image of its face. But what is this inclination without an efficacious counterweight, if not assent?

If we truly grasp this point, we will then understand the expressions in which Saint Thomas constantly returns to the affirmative side of opinion. In opinion, he says, the mind is inclined more towards one side than towards the other.⁷ The opining person accepts one of the two alternatives.⁸ Elsewhere, he makes Aristotle's words his own: “While we can imagine at pleasure, we cannot opine at will.”⁹ And why, we might ask, if not because opinion is related, as effect to cause, with a preponderance of truth?—Here, he establishes that opinion is already no longer research, but an affirmation, (enunciatio), and the one who truly opines holds that his opinion is true.¹⁰ And elsewhere, he argues that opinion is an intellectual determination, whose regulating norm is truth, that to deviate from this rule is to commit an intellectual sin¹¹ and, finally, that opinion is a kind of assent.¹²

II. Influence of the contingency of the probable on opinion. The contingency of opinion corresponds to the contingency of probable truth.¹³ In our earlier discussions, we presented the three modes of contingency pertaining to the probable: contingent matter, incapable of being the object of absolutely certain knowledge; matter that is necessary in itself, though apprehended with the aid of signs that do not reach to the depths of things, their profound or decisive reasons; or a necessary matter, though grasped imperfectly, as a result of the imperfection on the part of the mind grasping it. In all three cases, at the moment when it activates the mind, the intelligible does not have the absolute determination that reduces intellectual potency [to act] and leads to adherence. “It is of the very nature of opinion,” says Saint Thomas, “that what is esteemed to be such or such is likewise esteemed to be able to be otherwise.”¹⁴ And this is so even while the mind esteems it to be true, as the corrected text in the Leonine edition declares even more expressly than the old text: De ratione opinionis est quod id quod quis existimat, existimet possibile aliter se habere.¹⁵

What is this possibility? What is its cause? Could it not be opposing probabilities, which, without being able to tip the balance right now, at least delay and counteract its inclination?

By no means, because—and this point cannot be repeated too often—the possible is not the same thing as the probable. The possibility in question is the possibility inherent in all contingency. Since the proposition I accept as true by opinion-assent is a contingent proposition, absolutely speaking, it can be false. Such a possibility simply means that we are not currently dealing with a self-evident manifestation of the absolute truth.

And here is tangible proof of the point: normally, in every process of discovery, in every inventio, that really progresses toward its goal, the probable (being defined as that which really approaches absolute truth) leads to the absolute truth itself, est via ad scientiam. Whenever things go their normal way, the formulation expressed as an opinion is ultimately consecrated as the formulation expressed by science. Now, when scientific knowledge is thus brought about, it is quite clear that there is no longer any real probability against it. And there was, therefore, none before either. The possibility of error contained in the statement of opinion, now having become a scientific truth, did not imply the existence of any opposed probability. The possibility of error inherent in opinion comes simply from the fact that opinion is not yet science, although it tends towards it and often becomes it. It reminds us that, in matters of truth, as in everything else, the relative, however important, is never the absolute.

But, the objection will be raised: what is possible sometimes happens: Quod est possibile esse, aliquando est. Logically, then, there will be cases when the possibility of error inherent in opinion-assent will be actualized, when error will be discovered, when the contrary opinion that you declared was improbable and nil will, in fact, replace its rival.

In fact, this is how things sometimes turn out. The contingency of opinion translates into the appearance or reviviscence of adverse probabilities.

And, the objection continues: in the latter case, it is not difficult for us to say why this reviviscence took place. While I adhered to the opinion that I considered probable, I did not fail to see in its surroundings opposed motives that were sufficiently well-founded for me to have considered them probable, before deeming them outmoded. It is simply the case that such motives can now that take over anew, either because they now appear in a better light or even, without any intrinsic change, simply because the supplanting opinion has found itself for some reason, newly uncovered, in a previously bad position. And therefore, on its own, the opinion previously deemed improbable had not ceased to retain its probability.

And thus: the contingency or possibility of error inherent in opinion often covers over the existence of probabilities in the opposite direction.

In response: 1˚ It is certain that opinion, because it is contingent, does not exclude the possibility of contrary probabilities. He who concedes what is more also concedes what is less. Now, contingency in matters of truth is nothing other than a possibility of error, and therefore a possibility of contrary truth—and, therefore, a fortiori, a possibility of contrary probabilities. Otherwise, contingency would mean nothing.

But it is no less certain that the contingency of opinion does not, of itself, imply the existence of opposite probabilities. And, as we already said, in proof of this is the fact that opinion is the natural prelude to science. To assert that the contingency of opinion necessarily entails opposing probabilities is a baseless assumption.

In order for an alleged probability opposed to an assent of opinion to acquire the reality that this assent denies to it, something more than the contingency of opinion needs to be invoked: we need to provide a positive proof, with all the new costs associated with that, for the existence of such probability. Such a proof does not imply contradiction, so long as opinion has not yet become science.¹⁶ But a chasm separates non-contradiction and existence, logical possibility and real possibility resulting from the presence of real and effective causes of assent. Actori incumbit probatio: let the alleged candidate for opinion-assent prove himself. That’s all we ask.

But, it will be said: in some cases it does prove itself; and just as you conclude from the fact of the transformation of opinion into science that the contingency of an opinion does not always imply the existence or the real possibility of contrary opinions, so too can one conclude, based upon the fact of the substitution of a new, previously neglected or rejected opinion in place of a reigning opinion that the contingency inherent in opinion entails, in certain cases, this existence or this real possibility and not merely a pure logical possibility.

This objection leads us to a second and definitive solution.

Therefore, I respond: 2˚ Yes, in some cases, a new opinion does indeed replace another opinion. But why is this? Quite simply, it is because, per accidens, we had judged to be probable what in fact was not probable. Errare humanum est. Similar errors occur in scientific and even metaphysical matters. Sometimes we reason wrongly or judge to be demonstrated something that, in fact, has not been.¹⁷ This does not prevent science and metaphysics from being science and metaphysics.

The same applies to opinion. There are, in fact, false opinions, wrongly assented to on the basis of merely apparent probabilities. As things go, this in fact happens far more frequently in opinion than in science. This is due to the contingency of the matter attributed to probability and that of the signs that are its benchmarks—the easy access that opinion offers, as we shall see later, to the interventions of the will. All this does not prevent opinion from being, per se, the normal prelude to scientific truth, the unswerving path that leads to science. If there are exceptions, we don’t care about them. In any order of things, failures are the inevitable price to pay for the promotion of a better good.¹⁸ Natura deficit in paucioribus, nature fails in a few causes: that’s already something. Science, which in itself is infallible, immediately upon being realized in the mind then gives way to sophistry. How could opinion not be exposed to such accidents?¹⁹

Therefore, whenever we can establish that one opinion has given way to another, this is a sign that the first was merely an apparent opinion. The cause of the reversal is not the contingency of the opinion, but simply the total absence of the value that makes up opinion itself. This is a common and vulgar accident, which can befall any perfection, which passes out of the region of the abstract and essences in order to be realized in the concrete.

In itself, opinion remains, despite its contingency, a positively true assent and, therefore, a real intellectual perfection, enriching the human mind with an entire province subject to probability, inaccessible to science. Even in the domain of science, opinion projects its investigations and thus prepares or prolongs the full evidence of absolute truth.²⁰

* * *

Saint Thomas always has in mind these two poles involved in the question of opinion: assent and contingency. But, depending on the aspect of the problem under consideration, he sometimes insists on one side, and at other times, on its opposite. And those are not accustomed to his works through long and devoted reading are often brought to a halt by these divergences of expression. Reading the passages where the Holy Doctor insists on contingency, some see a denial of the assent value of opinion, or even neo-probabilist professions of faith. Therefore, as an epilogue to this section, it will be useful to give a harmonized view of all the remarks made by St. Thomas that have a representative value. We will omit doublets. These texts can be divided into three categories:

1˚ There are those texts that seem to exclude assent: “He accepts one part with fear of the other, and therefore does not assent.” (Accipit unam partem cum formidine alterius, et ideo non assentit).²¹ “He who doubts does not express assent since he does not adhere to one side more than the other... Similarly, neither does the person who opines, since his acceptance is not strengthened regarding the other side” (Dubitans non habet assensum cum non inhaereat uni parti magis quam alii... Similiter nec opinans, cum non firmetur ejus acceptio circa alteram partem).²² “It belongs to the very notion of opinion that one thing is accepted with fear that the other position might be true; hence it does not involve firm adherence.” (De ratione opinionis est quod accipiatur unum cum formidine alterius, unde non habet firmam adhaesionem).²³ Opinion does not involve firm assent, for as the Philosopher says, it is something weak and feeble according to the Philosopher. (Opinio non habet firmum assensum. Est enim quiddam debile et infirmum).²⁴ That which inclines toward the formation of opinion in whatsoever way, or even strongly, is not a sufficient inductive reason; hence, it does not compel, nor through this can there be a perfect judgment concerning those things to which it assents. (Quod inclinat ad opinandum qualitercumque vel etiam fortiter non est sufficiens inductivum rationis: unde non cogit nec per hoc potest esse perfectum judicium de his quibus assentitur.) ²⁵

None of these texts absolutely states that opinion is not assent. The first, which is the most radical, is followed, in the body of the same article, by the following explanation: “The person who is opining has cogitation without perfect assent, though he has a kind of assent. (Opinans habet cogitationem sine assensu perfecto, sed habet aliquid assensus.)”²⁶ So what is the source of the absolute denial: “And therefore, he does not assent (et ideo non assentit)”? Quite simply the fact that St. Thomas is speaking here under the influence of Avicenna and Isaac Israeli, who derived assentire from sententia,²⁷ and defined the latter as: “A distinct and utterly certain conception of the other side of a contradiction.”²⁸ Having admitted this absolute concerning the assent of opinion, all that is left for us is to conclude with Saint Thomas: “Through assent (namely, utterly certain assent) belief is separated... both from doubt and from opinion. (Per assensum [scilicet certissimum] separatur credere... et a dubitatione et ab opinione.)”²⁹

In the other texts, the reader will note that, no matter how accentuated the reservations, we always there find an expression noting the positive character of the assent of opinion—“accipit unam partem; acceptio circa alteram partem, etc.—whereas doubt is declared to have no kind of assent. But this assent is neither perfect nor absolutely firm, which is the same as saying that it is contingent.

The word formido, if understood as being a fear intrinsic to opinion, means nothing other than the contingency of the act of opinion, as Domingo de Soto points out in his penetrating commentary on the Analytics, to which we shall return shortly. And the reason for this is obvious. Fear is a volitional phenomenon. Strictly speaking, an intellect does not fear. If its judgment is not perfect, it has apprehensions—but, through thought. We will soon consider this intellectual apprehension, and there we will see that it indicates nothing that isn’t contained in the idea of contingent assent. Moreover, I do not deny that volitional fear is normally found, not in opinion (which is an act of the mind) but, rather, in the person who opines, on account of the part that the will can have in this act. And this is why I consider it below as a property consequent to opinion, though extrinsic to its essence.³⁰

As for Aristotle’s epithet, “Opinio est quiddam debile et infirmum,” it declares nothing more than what they are intended to assert, namely that the assent of opinion is not firm, in the sense of being not necessary: non cogit. Their depreciatory intention is simply a manifestation of what every true philosopher feels when he compares the relative and the absolute. The relative nonetheless does remain what it is.

2. Next there is a group of texts that are more worrying at first glance, attributing to opinion either a) movements of doubt or b) an assent of simple preference, seeming to include an opposite assent.

a) “A man opines concerning that to which he adheres when his understanding does not terminate to one thing, while there continues to remain a movement towards the opposed statement. (Homo opinatur illud cui adhaeret et non terminatur intellectus eius ad unum, quia semper remanet motus ad contrarium).”³¹ “They indeed accept one side, though they always remain in doubt concerning the opposite. (Accipit quidem unam partem, tamen semper dubitat de opposite).³² “And if this is with doubt and fear of the other side, this will be an opinion. (Et si quidem hoc sit cum dubitatione et formidine alterius partis, erit opinio).”³³ These texts say more than a simple possibility of error. They point to positive acts of the mind, based on this possibility, and moving in the opposite direction to the probable, to the point of generating doubt. Yet these contrary movements, and above all this doubt, seem to be in contradiction with true assent.

However, St. Thomas does not judge this to be so, for he immediately interprets both texts to mean that assent is imperfect because it is accompanied by fear. Now, we know what he means by fear, formido.

Clearly, there are movements of the mind in the opining person that run counter to his assent. But this is due, as St Thomas says, to the fact that his intellect is not determined ad unum by opinion (as it is by science). This does not prevent him from assenting: “Homo opinatur illud cui adhaeret, et non terminatur intellectus ejus ad unum, quia semper remanet motus ad contrarium.” The same phenomenon occurs in faith, which is nevertheless a certain assent, and even in supernatural faith, because it has in common with opinion the fact that it is a thought that has not yet found its intellectual terminus, cogitatio.³⁴ “The believer experiences some movement of doubt due to the fact that his intellect does not of itself terminate in the vision of the intelligible object. (Credenti accidit aliquis motus dubitationis ex hoc quod intellectus ejus non est secundum se terminatus in sui intelligibilis visione.)³⁵ It is therefore inappropriate to use such texts to argue against the assent value of opinion.

Moreover, upon closer examination, these texts reveal that the doubt they portray is not what St. Thomas commonly understands by doubt. This “doubt” is one-sided: motus ad contrarium,—dubitat de oppositâ,—cum dubitatione et formidine alterius partis. Its terminus is not the object of the opinion, but its opposite. True doubt, on the other hand, concerns both sides of the alternative: “Faith... differs from opinion, which accepts one of two opposites with fear of the other, and from doubt, which wavers between two contraries.(Fides... ab opinione differt, quae accipit alterum oppositorum cum formidine alterius, et a dubitatione quae fluctuat inter duo contraria.)”³⁶ “The doubter does not give assent, since he does not adhere to one side more than the other; similarly, neither does the person holding an opinion, since his acceptance is not strengthened around one [side]. (Dubitans non habet assensum cum non inhaereat uni parti magis quam alii; similiter nec opinans, cum non firmetur eius acceptio circa alterum.)”³⁷ The difference is clear. The doubter succumbs to temptation. He focuses successively on the two parties involved, without assenting to either. The person who opines remains at his point of attachment [to the truth]. Nonetheless, his thoughts are stirred, pushing him to the opposite side: but in order for him to do what? To express a contrary assent? Not at all: Dubitat de opposita. This is not adherence. Thus, the person who opines neither doubts what he is adhering to, nor adheres to the opposite alternative. Ultimately, his opinion is an adherence: “Man opines regarding that to which he adheres. (Homo opinatur illud cui adhaeret.)” ³⁸ “He who assents determines his intellect to one side of the contradiction, thereby determining it. (Qui assentit intellectum ad alterutram partem contradictionis determinat.)”³⁹

b) “The intellect assents to something... through a kind of choice volitionally leaning towards one side more than the other. And if this takes place with doubt and fear of the other side, one will have an opinion. (Intellectus assentit alicui... per quamdam electionem voluntarie declinans in unam partem magis quam in aliam. Et si quidem hoc sit cum dubitatione et formidine alterius, erit opinio.)”⁴⁰ “Opinion involves a kind of assent, insofar as one adheres more to one side than to the other. (Opinio habet aliquis assensus in quantum uni adhaeret magis quam alii.)”⁴¹—We leave the question concerning the will’s participation in the formation of opinion to the next section. We are only noting in these texts what is relevant to our present research. Now, if these expressions—in unam partem magis quam in aliam, uni magis quam alii—indicate a preponderance in the assent of opinion, they seem to connote, one might say, an opposite, weaker assent... If we support one side more than another, we support the other—less, no doubt, but still we do support it.

This interpretation is unfounded. Whenever St. Thomas says that opinion adheres more to one side than to another, he does so in order to situate opinion vis-à-vis doubt, concerning which he said: “The person who is in a state of doubt does not have assent, for he does not adhere to one side more than to the other. (Dubitans non habet assensum, cum non inhaereat uni parti magis quam alii).⁴² And elsewhere: “Sometimes the intellect does not lean more towards one side than the other… And this is the disposition of the doubter, who fluctuates between the two sides of a contradiction. (Quandoque intellectus non inclinatur magis ad unum quam ad aliud... et ista est dubitantis dispositio qui fluctuat inter duas partes contradictionis.)”⁴³ To dismiss opinion and deny this fluctuation, the imposed formula is: “Opinion adheres more to one of the opposing sides than to the other. (Intellectus inclinatur magis ad unum quam ad alterum.)”⁴⁴ This formula is a pure negation of the previous one. Now, for this negation to be effective, it is not necessary for the opining person to have two unequal assents: it suffices that he have only one. This much is clear. And this is why St. Thomas always explains this, uni magis quam alii, by the single assent of opinion: “Sometimes the intellect leans more towards one side than to the other, but still, such leaning does not sufficiently move the intellect to determine it totally toward one side. Hence, it accepts one side, while still having doubts concerning the opposite. And this is the disposition of the person who opines opinion. (Quandoque intellectus inclinatur magis ad unum quam ad alterum sed tamen illud inclinans non sufficienter movet intellectum ad hoc quod determinet ipsum in unam partem totaliter. Unde accipit unam partem, tamen dubitat de oppositâ. Et haec est dispositio opinantis.)...⁴⁵ Dubitare de opposita: this is the assent given to the side to which the opining person is least inclined. Behold how he adheres to that one side less than to the other. What a unique kind of adherence!

3˚ A seemingly more far-reaching text, though one that is even easier to explain, is this one: “Opinion relates to both the true and the false. (Opinio se habet ad verum et falsum.)”⁴⁶ The following text, “Opinion and suspicion can be of both truth and falsehood (opinio vero et suspicio possunt esse veri et falsi),”⁴⁷ already brings with itself the corrective of possibility—possunt—which brings us back to the possibility of error inherent in the contingency of opinion. But St. Thomas explains himself in a way that leaves no obscurity about his thought: “Since the act of the intellect is good in that it considers the true, it is necessary that a habit existing in the intellect can be a virtue only if it enables the person possessing it to infallibly declare the truth. For this reason, opinion is not an intellectual virtue, but science and understanding are, as is said in the sixth book of the Ethics. (Cum actus intellectus sit bonus ex hoc quod verum considerat, oportet quod habitus in intellectu existens virtus esse non possit, nisi sit talis quo infallibiliter verum dicatur; ratione cujus opinio non est virtus intellectualis, sed scientia et intellectus, ut dicitur in VI Ethicorum.)”⁴⁸ “It happens that by opinion and suspicion falsehood is sometimes declared... However, it is against the nature of virtue to be the principle of a bad act. And thus, it is clear that suspicion and opinion cannot be called intellectual virtues. (Contingit quod opinione et suspicione quandoque dicitur falsum... Est autem contra rationem virtutis, ut sit principium mali actus. Et sic patet quod suspicio et opinio non possunt dici intellectuales virtutes.)”⁴⁹

Such is my attempt to provide a concordance of the relevant texts in Saint Thomas. I submit it to the judgment of competent Thomists. They may feel the need to provide some remarks on some points of detail. But, on the other hand, I am sure they will recognize that this harmonization leaves no doubt as to the master thread in St. Thomas’s thought concerning this matter: opinion is contingent assent.

2. The subject of opinion and its subjective factors

As St. Thomas says formally: opinion is an act of the speculative intellect—of the possible intellect.⁵⁰ As every immanent act is necessarily received in the faculty that produces it, the immediate subject of opinion is the intellectual power.

But is it the intellectual power alone?

A similar question arises for faith in testimony, and it is commonly resolved in the negative. The act of faith issues from reason in its speculative operation, yet the subject of the virtue of faith is not speculative reason alone but, rather, speculative reason as penetrated by the influence of the will: non est in intellectu speculativo absolute sed secundum quod subditur imperio voluntatis.⁵¹ And the reason for this—which, moreover, is something having general application,⁵² applying equally to prudence, temperance, and fortitude—is that, while faith is comes to its consummation in an intellectual act, it originates in an act of the will which is essential to it. Given the obscurity of the object of faith, there would be no intellectual determination without this impulse toward the good. Lacking it, the act of faith cannot be elicited.

Now, the object of opinion is also, if not obscure, at least contingent. On its own, it is powerless to determine the mind. Nonetheless, opinion is a positive adherence. Is not this adherence due to the influence of the will, to a kind of choice, analogous to that of faith? And hence, should not the subject of opinion also be complex—at once an executing intelligence and an imperative will?⁵³

Does Saint Thomas lean in the direction of claiming that opinion has this kind of partially appetitive nature?—In a passage of the Summa, which seems to be an a priori and synthetic exposition of the various ways in which assent can occur, he expresses himself as follows:

The intellect’s assent is produced in two ways: 1˚ under the action of the object itself, in cases of self-evident truth (first principles) or inferred truth (scientific conclusions); 2˚ without sufficient motion on the part of its object and, therefore, as an effect of a volitional choice inclining (this assent) towards one side more than the other. If this is done while hesitating and fearing the other alternative, it will be opinion; if, with certainty and without fear, it will be faith.⁵⁴

This is not an isolated text. In ST I-II, Saint Thomas expresses himself as follows:

If apprehension furnishes data in such a way that the intellect naturally adheres to them—as in the case of first principles—assent or rejection do not lay within our power: they belong to the order of nature… However, there are data that do not produce such a conviction in the intellect that it cannot, for whatever reason, give or withhold its assent, or at least suspend it. In this case, assent or disagreement lays within our power and falls under our command.⁵⁵

Opinion is not explicitly named in this second passage. Nonetheless, it is clearly in the crosshairs, along with faith. As regards the abstract principles involved, this text reproduces what was said the previous.

These texts are the only ones where we find in Saint Thomas the idea that opinion formally depends upon the will. The first, truth be told, is very explicit. No text in him contradicts it in an absolute fashion.⁵⁶ Moreover, it allows us to account for the formido errandi perpetually attributed to opinion by the Holy Doctor, for we can understand this fear as being a kind of volitional sentiment, which seems more literal. Thus, we cannot, and should not, pass over it before explaining it. It raises two distinct problems:

1˚ Is intervention by the will essential to the assent of opinion?—And if not:

2˚ How can Saint Thomas say that both faith and opinion require the motion of the will, indeed for the same reason (i.e., the object’s motive insufficiency), whereas this motion is essential to faith?

I.—The will’s intervention in opinion.—“St Thomas’ thought concerning the will’s intervention in opinion must be understood as referring to the normal course of things and to what is self-evident given the nature of the realities involved. Intelligitur regulariter et per se ex naturâ rei.” Such are the rather enigmatic words of Domingo de Soto in his resolution to this issue.⁵⁷ Moreover, he maintains that this intervention by the will is not essential to opinion, that it allows exceptions, and that it nevertheless habitually belongs to it, always ready to be elicited.⁵⁸

We believe that his thought and that of Saint Thomas can be interpreted as follows:

Adhering to the probable is undoubtedly a purely intellectual act in itself. However, on the other hand, the probable represents a good for the whole man, and we will come to say what kind. As such, it is of interest to the will, the appetite of the complete living being, appetitus animalis,⁵⁹ whose function is to be moved by everything that is a good for man and to strive for its realization.

It is first and foremost the good of man as an intelligent being. From this perspective, man aspires to the good of his intellect, which is truth. Through its approximation to truth, the probable truly represents (albeit in a still relative way) this good for the intellect. To approach the truth is already an intellectual good. It is easy to see why the will cannot be disinterested in this good and why, without intervening in the formal relations between the intelligible object and intellectual knowledge (which substantially constitute opinion-adherence), the will envelops in its self-interested activity the activity of the intellect, in order to promote, preserve, and defend, from its perspective, a truly well-founded opinion. This is a completely external intervention, a juxtaposed activity, which leaves everything in place, while nonetheless, through its resistance to unjustified fears, contributing to the consistency of opinion. This at least furnishes an initial interpretation for the expressions in Soto where he recognizes an intervention by the will as something normal and self-evident, given the nature of opinion.—We might add that, by virtue of its contingency and the temptations that follow, opinion is particularly susceptible to such volitional reinforcement. Science defends itself. By its very nature, opinion is less robust; scruples or unreasonable hesitations can practically rob the intellect of what is, nevertheless, one of its assets. It must be watched over by the faculty that oversees our praxis, the purveyor of the whole of life in its integrity, the will.

But, secondly, by the nature of its content, the object of opinion can interest the will in a very particular way. The probable is a contingent truth; contingent truths have as their object particular beings, and particular beings represent to the being endowed with a will those very goods which are more capable of impressing it, for they are the usual and proximate object of our preoccupations and of its inclinations. Loftier intelligibles represent goods that are undoubtedly nobler, but whose use is less frequent. Hence, it is quite understandable why the human appetite is inclined to follow very closely the progress, successes, or failures of opinion, which is precisely the intelligence-gathering capacity concerned with these connatural goods, and why it intervenes at any moment in order to move itself and support a particular opinion with the force of its desire or repugnance. Undoubtedly, as we have seen (with Aristotle), this does not go so far as to give rise to an opinion in the same way that we give free reign to our imagination:⁶⁰ in this respect, Saint Thomas notes that an opinion is not formulated in the mind without an objective reason. Nonetheless, as the Philosopher notes a little further on, while the imagination does not set the appetitive passions in motion (since we are aware that they are fictions) the opinion we form, for example, concerning difficulties, or concerning terrible dangers, or desirable things, moves us immediately.⁶¹ Why does this happen? Precisely because it is probably real. Opinion, therefore, places the will in relation to goods or evils that are probably real. Is not this of great interest to the faculty of the good?—From this point on, we can see that, normally and of itself—of itself, that is to say, not on account of its purely intellectual formation, but because of its habitual content—opinion arouses an appetitive activity.

And thus, without needing to reject what we determined concerning the intrinsically intellectual character of opinion, we can justify St. Thomas’ assertions attributing a normal intervention, per se, ex natura rei, to the will in opinion.

On the one hand, in fact, although the probable represents an object of speculation, it cannot free itself from the accompaniment of the objective ratio of goodness inherent in the true: the probable is good, because it approaches the absolute good of the intellect; and it is also good because it presents as something real a good of the whole man, all the more deserving of appreciation to the degree that it belongs to contingent realities, the preferred object of the will. And so, on this objective side, the probable is penetrated by aspects of goodness, which although they remain external to it, nonetheless are inseparable from it, per se, ex natura rei.

On the other hand, although opinion itself is, in itself, a purely intellectual act, it cannot be separated from the man whose act it is. In man in the concrete, voluntas sequitur intellectum. Although external to the intellect, the volitional phenomenon necessarily accompanies the appearance of the intelligible, per se, ex natura rei. The nature of things is the very functional link between the exercise of the will and the exercise of the intellect, the former’s natural provider. Even if the object offered by the intellect were purely speculative and did not represent a good, the conquest of the truth itself would still be a human good.

But what is a phenomenon that, without belonging to the essence, nevertheless always accompanies it, is necessarily connected to it, and flows from the essence, EX natura rei. This is what we call a characteristic property, or a proper effect, which amounts to the same thing. It is not, as the scholastics say, per se, primo modo; rather, it is per se, secundo aut quarto modo.⁶²

Thus, for both objective and subjective reasons, the cooperation of the will with opinion is a property external to the essence of opinion, though characteristic of opinion. And this is certainly the meaning of the texts of Saint Thomas cited above.

II. - The will’s intervention in faith and opinion. Points of agreement and of difference.—In the text we attempted to explain, the cooperation of the will is seen as a phenomenon common to faith and opinion. Now, the will is essential to faith; the motion of the will influences the specification of the act of faith⁶³ and, thus, reaches the essence of the act, since every tendency, every act in particular, derives its essential determination from the object to which it tends.

This invites us to clarify the role of the various volitional interventions found in faith, opinion, and even science. We will leave aside the motion of the will in exercise, namely, the simple application of the intellectual power to these various acts, as indeed to all human acts.

The interventions we are here considering are two in number: one common to faith and opinion and found to some degree in science; the other reserved for faith and testimony.

A.—Common intervention.—This occurs whenever the object of apprehension evokes the idea of a good. This is the case for the moral sciences, religious faith, and opinion, whose object belongs to the order of contingencies, akin to the order of practical realities. The cause of this volitional intervention is the well-known psychological law: voluntas sequitur intellectum.

We must, however, note a difference in the ways in which the good acts on the will, depending on whether it accompanies scientific knowledge, opinion, or faith.

As far as science is concerned, the effect produced is a simple agreement of will, resulting in an active reaction that makes us consent more strongly to the object presented, and adds to scientific adherence that extrinsic supplement which makes for scientific convictions. Science, in fact, does not lend itself to motor reactions affecting the relationship between subject and object.

In opinion, there is the same fundamental attitude of the will. However, because of the contingency involved in the assent of opinion, we understand that the reverberation of appetition has more marked effects. Without changing the intrinsic relations between subject and object (since opinion is essentially speculative in nature, and because it is inherently impossible to have opinions merely at will), the will reinforces and supports with its preferences the opinion that pleases it, for reasons of its own, which are foreign to the speculative plausibility of the opinion itself, and naturally, it does the same in the opposite direction for opinions that displease it.

This appetitive reverberation can also be found in the act of faith. “We experience,” says Soto, “that where evidence does not impose itself, affection takes on sovereign importance, some believing in Saint Augustine, others in Saint Jerome, others in Saint Thomas, etc.... When we are fond of a doctor, we are more likely to agree with his opinion than with that of another, on equal grounds.”⁶⁴

This special kind of appetitive reaction takes place, in faith as in opinion, because of their lack of evidence. Here is a kind of invitation and request for volitional supplements.

And we must here note that these supplements do not indifferently labor on behalf of truth or error. When they do not distort one’s judgment, and when their objective reasons are sound, they exercise in the direction of true goods and can thus help to ensure our possession of the truth. The entire doctrine concerning the formation of moral conscience, in those difficult matters that give rise only to opinion, derives from this observation, as does the doctrine of the moral substitutes of credibility.⁶⁵ The verdict rendered by prudence must first and foremost take into account objective realities, the elements of good and evil that appear in the object, but once likeliness (le vraisemblable) has been obtained, it must be empowered by reflex principles⁶⁶ belonging the practical order, to serve as a categorical rule for an action that can only be categorical. The fulcrum for this supreme rectification is to be found in uprightness of the will’s intention. Therefore, we can easily see how, when firm and lofty, this intention can give rise to initiatives, directions, and forward impulses that legitimately complement speculative assurances, without ever absolutely replacing them.

This element, shared by both faith and opinion, is what St Thomas calls appetitus quidam boni repromissi in supernatural faith.⁶⁷ Of course, in the latter case, the appetite for the good, because of its supernaturality, offers a peerless kind of guarantee, one that neither human faith nor opinion shares. In arguing that the volitional motion in question is common to opinion and faith, even supernatural faith, I am retaining the differences. My point is simply this: in all three cases, on the one hand, the object is not self-evident, whatever might be the reason for this lack of evidence—insufficiency of motives in opinion, or obscurity in faith. This inevitability authorizes the will to undertake initiatives that cannot be found in science. On the other hand, motives belonging to the order of the good explain, by virtue of a uniform psychological mechanism, the extrinsic intervention of the will. I would add that, under certain conditions, these volitional interventions are legitimate and legitimately contribute to strengthening opinion and faith. To take Soto’s example again: is it not obvious that affection for tried and tested doctors such as St. Augustine and St. Thomas legitimately strengthens a Catholic theologian’s adherence to certain theological opinions? A fortiori, the love of eternal goods will legitimately intervene, servatis servandis, to reinforce the prudential verdict or judgments of credibility and credentity.

It is to this motion common to faith and opinion that Saint Thomas alludes in the alleged text. Regularly, per se, ex natura rei, faith and opinion involve this intervention by the will, because both are inevitable on the side of their object, because both are capable of speaking to man about his good. In the case of opinion: because moral things, res humanae, constitute its proper domain, and also because the contingent objects it deals with are very particularly a matter of appetition. And in that of supernatural faith: because its object is immediately related to man’s destiny.

But this intervention by the will, however natural and imposed it might be, is not the motion that theologians declare to be essential to faith. It remains for us to demonstrate this point by establishing that, in the case of faith in testimony, the will exercises an influence upon the intellect in a way that is irreducible to the motion of exercise and to the motion that flows from the appetite for the moral good.

B. Special intervention by the will.—The object of faith in testimony and the object of opinion are both non-evident, but not in the same way. The object of opinion is non-evident in the sense that it is contingent in nature. It is not rigorously demonstrated. It is only verisimilar [vraisemblable]. And thus, from the perspective of truth, it furnishes an object which does not suffice for reducing the intellect [completely to act in adherence], though it does suffice for provoking assent, directly and of its own accord.

By contrast, the object of faith in testimony is totally unavoidable. A historical fact, for example, has, absolutely speaking, no reason to exist for the mind apart from the truthfulness of the testimony that affirms it. And this is all the more true for the case of divine mysteries.⁶⁸ Faith derives nothing from its immediate object. The truth of its object is entirely relative to the testimony. This is credibility.

Now, the human mind has two possible aptitudes towards testimony: an attitude of theoretical research and an attitude of intellectual dependence.

The first attitude is that of the mind that verifies, in an exclusively speculative way, the evidence of the witness’s veracity. This is the attitude of the historian and the magistrate. And, given that proof of the truthfulness of a witness is not a question of science but, rather, of probability, therefore the credibility of an assertion obtained in this way is ultimately no different from the truth of opinion, or ordinary probability. In the same way, in his Topics, Aristotle makes no distinction between the probability that results directly from the sight of objective verisimilitude and that which results from the testimony of all, from a number of people, and from those who have a particular competence.⁶⁹ There is no trace of a special volitional intervention in faith in testimony understood in this way. With a cold gaze, the historian analyzes the elements of veracity for a testimony and progressively transfers each probability acquired for or against, in credit or in debit to, the assertion that seeks to rely on this testimony. It is a question of logical correction. And the result is the probability of the assertion and scientific faith: “Even for the great facts of history…, it is only a question of a maximal accounting of probabilities based on inferences which it is never possible to verify entirely…”⁷⁰

But another attitude is possible, at least in certain cases of testimony, and this second attitude essentially involves the will’s intervention in the intellectual act. Such is the case whenever the knowledge of one being is, by the very nature of things, the rule for the knowledge of other beings.

This is the case for God in relation to human knowledge. Let us look at a short passage from St. Thomas, who describes two attitudes: faith in opinion, and what we today call, without perhaps having sufficiently penetrated its foundation and mechanism, faith in authority. “To believe in a man, without the support of a probable reason,⁷¹ is a kind of levity, for the knowledge of one man is not naturally ordered to the knowledge of another man, so as to be measured thereby. However, human knowledge is ordered to the First Truth in this way.”⁷²—Consequently, another man’s knowledge, because it is not naturally my intellectual rule, represents a good of my mind only insofar as I have verified, toties quoties, each and every time, its validity. If, therefore, I adhere volitionally to the intellectual good represented by human testimony, it is less to his authority that I adhere, than to the reasons by which I have verified that what this authority says has probability. Thus, in the formation of human faith, the will plays a role of mere transmission: it transfers to the benefit of the assertion the probability of the verified witness.—By contrast, when there is a natural hierarchy between two reasons, one superior, the other inferior, the scientific authority of the superior reason inherently represents the good of the subordinate intelligence. “Whenever two beings are ordered to one another, it belongs to the perfection of the inferior being that it be subject to the superior being: thus it is a good for the passions of the concupiscible to be subordinated to reason.”⁷³—“Given that our natural knowledge is related to divine knowledge as inferior to superior, when our reason acquiesces (consentit) to the divine reason, it is an act of virtue, just as when the irascible submits to reason.”⁷⁴

Therefore, the authority of divine reason is, for every created reason, an absolute good to which the will must fasten itself for its own sake, indeed, absolutely. Once I am certain that I am in the presence of divine authority, my will gives itself to it, as to the absolute good of my mind [esprit], and when it turns to the intelligence to incline it to adhere to the testimony of this sovereign authority, it does so with the full élan of absolute adherence that the absolute good of the mind [esprit] deserves: “It is the good of the intellect that it be subject to a will that adheres to God. This is why faith liberates the intelelct, by the very fact that it makes it captive to such a will.”⁷⁵ This intervention by of the will is essential faith in authority, since it is only through the will’s intermediacy that the intellect finds itself under the sway of its essential rule.

And, because we are here talking about supernatural faith, we must here add that the manifestation of the good represented by divine testimony is not only certified (as in faith in opinion) by the probable arguments concerning the grounds for credibility but [moreover, and more essentially,] by the very testimony of the First Truth, which, in supernatural faith, has the first and principal effect of being its own guarantee.⁷⁶ Thus, none of the inadequacies of the volitional motion of faith in opinion are to be found in divine faith. And, therefore, as St. Thomas again says: “The reason that inclines the will to believe the truths of faith is the First Truth, which is infallible, whereas the reason that inclines the will to believe other things is only a fallible sign (opinion) or the words of a man who may be mistaken or deceived (faith in opinion). Hence, the will does not communicate an infallible truth to the person who believes these things, whereas it communicates such infallible truth to him who believes the articles of faith.”⁷⁷

The Vatican Council set its seal upon this entire doctrine by placing at the head of its description of the act of faith, not the motion of the will that comes from the vantage of eternal goods but from that which is set in motion by the First Truth’s authority over human knowledge: Since created reason is wholly subject to the Uncreated Truth, we are bound to render full obedience to God who Reveals.⁷⁸

Nor, moreover, should we think that faith in authority is found only in divine faith. This is undoubtedly a typical case, given how formal is the dependence of created intelligence upon the First Truth and how absolute is the regulative vigour of divine science, which goes so far as to bear effective witness to itself within the very sanctuary of conscience.

But wherever one mind naturally depends upon another, we will find the essential intervention of the will in the formation of faith. The best analogy is that of a child’s mind in relation to his parents. Here, intellectual dependence is no longer a metaphysical necessity, as in the case of God; nonetheless, it is first and foremost physical and natural.—Man’s dependence on his master is broader, and yet, here again, we find, mutatis mutandis, faith in authority and the affection for the good of authority that is inseparable from it. To this feeling of legitimate reverence may be related the fact pointed out by Soto, concerning the faith we readily express for certain doctors. We love them because they are like sources of true testimony.—Extending this still further, we could say that in all faith in testimony there enters a portion of the reverence felt for authority [une part de culte de l’authorité]. St. Thomas, following in the footsteps of St. Augustine, holds that veracity and, consequently, faith in the words of others, is the social bond par excellence. These two doctors base their teaching concerning lying on this, as a sin against society, which lives only on mutual faith.⁷⁹ Now, society is natural to man, and in this sense we can say that every mind naturally depends upon the science of others as upon a rule.⁸⁰ But it is clear that this regulating influence is, in practice, subject to such vagaries that the faith in authority that derives from it is more suited to the ideal city than to real society. Nonetheless, insofar as the indispensable conditions of truthfulness and sincerity are observed, faith in authority can be generalized, thus preserving for supernatural faith the broader analogical basis recognized by St. Thomas: “The believer is like a man who relies on the testimony of an honest man who sees what he, the believer, does not see.”⁸¹

Thus, apart from the common volitional motion, in which both opinion and faith participate, there is a motion of the will reserved for faith in authority, especially for divine faith. The common motion originates in the view of some kind of goodness, either that of the truth itself or that of the objects presented in the apprehension of truth (eternal goods or temporal ones). It belongs to opinion as well as to faith, per se ex natura rei, indispensably following upon every act of knowledge. The second motion is reserved for faith, not “scientific faith,” but faith in authority. It appears only when an intelligence finds itself under the sway of a regulative intelligence. Its motive is the actual veridicality of the intelligence that is its rule. This volitional motion finds its perfect and absolute realization in divine faith alone, and this is undoubtedly what led Soto to say that perhaps, “forte,” when Saint Thomas defined opinion as assent accompanied by fear, he included in this definition all human faith, which is subject to fear, since error is absolutely opposed only to Catholic faith.⁸²

Be that as it may, we can now see how St. Thomas was able to place opinion and faith equally under the will’s influence. This is a general influence, common to all acts of intellect lacking perfect objective evidence. There are exceptions to this law. And thus, it is not essential, but only normal, for opinion to be under the influence of the will. And so, the will is neither a necessary [causative] factor, nor the essential subject of opinion, any more than it is, in this same respect, a [causative] factor or essential subject of faith itself.

And, thus, we see how St. Thomas, on the other hand, was able to reserve for faith in authority—and, in particular, for supernatural faith—an essential volitional intervention, and why, in his doctrine, divine faith has as its subject not only the intellect, but also the will, or rather the intellect under the sway of the will.

Therefore, it remains the case that the assent of opinion is, in itself, a purely intellectual act, one belonging to the intellect and received in it alone.

3˚—The property of opinion: Formido errandi.

We argued earlier that fear, understood as a volitional phenomenon, could not be included in the essential definition of opinion. What we just established about the role of the will in opinion confirms our assertion, by virtue of the principle eadem est ratio contrariorum. If the will is not essential to opinion when it comes to inclining its assent, how and why should it be essential in regard to what is opposed to that assent?

Nonetheless, we have suggested in passing the idea that formido errandi, in the sense of a volitional phenomenon, can be seen being a property of opinion. It remains for us to justify this assertion.

Aristotle did not deal with this perspective. The word “fear” itself, if Soto is to be believed, is absent from his studies of opinion:⁸³ “What today’s doctors mean when they say that opinion is an assent accompanied by fear, Aristotle calls a contingent assent... For him, fear is not the intrinsic reason for opinion, as it is for moderns.”⁸⁴

This position is a particular case of the philosopher’s logical formalism. A logician must see opinion as nothing more than a reaction by the intellect before a perceived object. Thus abstracted, the judgment of opinion is defined exactly by these two traits: assent and contingency in assent. The rest, which is up to the man who opines, has nothing to do with a definition.⁸⁵

In St. Thomas, by contrast, fear is named each time, so to speak, opinion is discussed. There is no indication, however, that the Holy Doctor intended fear to refer to an appetitive phenomenon. Soto believes he means it, like Aristotle, in the sense of contingency.⁸⁶ For him, opinion and probability correspond to each other: assent in proportion to veresimilitude; contingency for contingency.

In any case, and this is certain, for St. Thomas there are judgments of opinion from which fear must be excluded. These are those that fall into the category of firm opinions. Saint Thomas and Aristotle set them apart under the name of faith, fides. We are not here talking about faith in testimony but, rather, faith in general, fides communiter dicta, i.e. established, firm, and certain belief.

“There is nothing opposed,” says De Soto, “to the fact that objective proofs can sometimes be so strong (tam vehemens auctoritas) that, despite the absence of evidence, citra evidentiam, the intellect is convinced, indeed without any volitional support⁸⁷—and even more so,” he adds, “despite the will’s resistance."⁸⁸ “Let one so judge: Rome exists. (For those who have not seen Rome) it falls into the category of opinion. Strictly speaking, however, it is made without fear, unless we use the term ‘fear’ to refer to the simple fact that it is not opposed to such assent that it might be false, since it is not self-evident.”⁸⁹

This exception means, once again, that volitional fear is not of the essence of opinion. What is essential is never lacking. It also follows that, if we admit that faith or firm belief participates in the specific nature of opinion, volitional fear is not even a property of opinion. Non convenit toti.

But we can also consider opinion as constituting a genus, characterized by the contingency of assent, a genus comprising two species, faith (the superior species) and ordinary opinion which, following the rule frequently observed for inferior species,⁹⁰ would retain the name of the genus.

If this is so, we can make this concession “to the crowd of modern dialectician” that Soto once scolded: volitional fear can be considered a property of ordinary opinion. In other words, it is extrinsic to the nature of opinion, though it is its proper and normal consequence.

To prove this, we need only recall the reasons that led us to admit that the intervention of the will, without entering into the essence of opinion, was nevertheless ordinarily called for by it, per se et ex natura rei.⁹¹

If the intellect is not itself moved by terrifying spectacles or pleasant vistas, because it can only see (i.e. reflect), nonetheless the intelligent man is so moved, because he can feel and will.⁹²

Now, the contingency of opinion has everything needed for moving the intelligent man. On the one hand, he is made for truth, and truth only fully satisfies him when it is absolute. Ignorabimus et restringamur, we shall not now and thus we will keep check on our hopes for the truth: this is a defeat. This is not what the human mind [esprit] first bets on when it launches forth. On the other hand, the practical truths that are most necessary to man's life—most necessary because through them he communicates with the mobile elements of his daily life—are precisely those truths that are moreover a matter of opinion and its contingency.

And thus, when the hard work of discovery, of inventio, comes to its close, when the probable, that “dawning radiance of tomorrow’s science,”⁹³ rises at the end of a laborious night, the man who lives his life precisely as a man—under the scientist absorbed in the progress of his thought—naturally and inevitably feels a sense of dread—"What if this possibility of error, as yet unreduced to certainty, were suddenly to spread out like a dark cloud in a stormy sky! What if today’s contingency became tomorrow’s error!" He does not doubt… He remains attached to the ray of light filtering through the clouds, like the captain upon his bridge in the dark of night, with eyes fixed upon the lighthouse on the shore, alternately shining and then disappearing back into the darkness. But, because he cannot yet see the luminous source of this ray, he experiences a feeling of dread. This fear is not essential to opinion, but in the man who thus opines, it naturally springs forth, per se, ex natura rei.

And a fortiori is this so when it is no longer a question of a particular good, such as the outcome of some speculative labor, but when great goods—whether goods of the body or those of the soul, whether individual, familial, or social goods, and indeed, above all, infinite goods—are, as it were, suspended from the opinion we manage to form concerning them. What is Copernicus’ opinion in comparison to the solution to the problem of immortality? But also, what anguish it causes when it only manages to establish itself as an opinion in our mind! Perhaps this fear, connected to opinion as its property, gives the final word on the state of mind of someone like Pascal, who, while professing that those who bring perfect sincerity “will be satisfied and convinced by the proofs of a religion so divine, all gathered together here”⁹⁴ in his Pensées, and thus convinced himself, nevertheless retains a kind of self-reservation against the possibility of an intellectual volte-face, that refuge and that sort of central defensive retreat known as “Pascal’s wager.”

IV. Probable Certainty

The analysis carried out in the first three parts of this study has provided us with the elements we need to solve the problem concerning “probable certainty.” Let us now deploy these instruments.

Earlier, we saw that assent to an opinion is essentially an act of the speculative intellect. It does, however, normally involve the cooperation of the will.⁹⁵

Hence, there are two modes for the formation of opinion-assent: 1˚ In exceptional cases, when the mind alone is at stake, an opinio vehemens appears, to which is reserved, not exclusively but by antonomasia, the term fides, i.e. very firm belief, subjectively very certain assent. Without having seen Rome, I believe that it exists—this is the example for this kind of faith found, in nearly stereotypical form, in older authors.—2˚ In cases when opinion is open to the will’s own concurrence, we then have common opinion. This, too, as we shall see, is called fides, on account of the subjective certainty to which it is susceptible, thanks to its strengthening by the will.

The genesis of “probable certainty” differs depending on which of these two classes of opinion is being considered.

1. - Firm speculative belief, Opinio vehemens—Fides.

Since will’s intervention is not essential to the formation of opinion (as we established) it is not forbidden that we admit cases when opinion owes its existence solely to the speculative intellect.

Experience confirms the truth of this observation. We have already noted, with De Soto, the case when the mind finds itself in the presence of such considerable authority that, despite the lack of absolute evidence, it finds itself convinced, without the will having taken the slightest part in its act, tam vehemens auctoritas ut citra evidentiam convincatur intellectus sine inclinatione voluntatis.⁹⁶ This is more often the case when opinion is derived from verified testimony—in other words, in scientific faith—than in opinion directly begotten by signs.⁹⁷ However, this conviction is also born under the exclusive influence of the object. This is what happens, for example, when a moral law is realized in concrete facts. In itself, a moral law is an analytic principle. Mothers love their children, and the poor want to be rich. These are not opinions but, rather, absolute and self-evident truths, based on analysis of the subject. It is in a mother’s interest to love her child, and it is in a poor man’s interest to desire to escape from his poverty. However, if we descend from this abstract region to the terrain of concrete realities, we will find exceptions. But they will be rare, because in spite of everything, the form that gives rise to the law subsists in real and concrete cases: in real mothers or in real poor people. And, consequently, in the concrete, it remains infinitely probable a priori, that a given mother loves her son, and that a given poor man wishes to become rich.⁹⁸ The comedian mentioned by St. Augustine, who had summoned all the people of Hippo to the theater to hear their most secret thoughts, was stating a probabilissima when he told this people that the only thing that merchants thought about was buying low and selling high.⁹⁹

To these cases when probability is based on the nature of the subject and thus possesses an a priori foundation, we must add all those cases when very high probabilities result from the a posteriori processes of invention. Often, signs accumulate and converge so clearly towards a single point that we can certainly retrace their steps and even carry out an experimentum crucis on them. In such cases, the possibility of error inherent in the probable no longer has the slightest chance of passing into act, at least for the mind that is naturally positive and realistic. It is nothing more than a kind of logical expression, from which the probable, without ceasing to be the probable, cannot be extricated.

Therefore, in such a case one will elicit a purely speculative assent, an assent that is objectively and subjectively very certain, and which nevertheless, because of its contingency, will not exceed the limit of opinion.

Like the older logicians, modern probabilistic logicians admit this major certainty caused by probabilissima, very probable things. But most of them refuse to hold it to be purely speculative certainty. This is a consequence of their ideas concerning the fear attached to all opinion and concerning the possibility of error which, according to them, implies that the opposite statement also has probability. The will would intervene, in order to dispel unwise doubts provoked by the presence of leviter probabilism corresponding to probabilissima and to shrink otherwise unfounded fears. In so doing, it would be guided by reflex principles such as: prudent reason must regard minutiae as non-existent (Parum pro nihilo accipit ratio). Hence this consequence: since these principles are practical and, moreover, foreign to the objective reasons that directly motivate opinion, the certainty obtained in the case at hand, in casu, would ultimately be practical and reflex.

The ancients would never have imagined such a stratagem. For them, in such a case, there was no fear of the contrary, no probability in the contrary. They, too, undoubtedly implied the principle, Parum pro nihilo accipit ratio, but instead of making it gravely explicit in the face of phantoms and imaginary fears, they regarded it as immanent to the natural functioning of reason. The good of reason is truth, and when it discovers in an exceptional probability a convincing sign of it, one that is like the ultimate disposition [to full and certain assent], it bears down upon this probable truth with all its weight, and does not even suspect the passing whisp that is opposed to it. It leaves no room for the will to intervene, either to help or to thwart it. Reason is not a scrupulous casuist who plays tricks with infinitesimal trivia. No, it is the vigorously realistic common sense of the Roman praetor, portrayed in a legal axiom, De minimis non curat praetor, the praetor is not concerned with trivial points.

This is how St. Thomas understood these things. As he writes:

We adhere only on the basis of objective reasons: the inherent light of first principles; the participated light of first principles found in the case of scientific assent; the light of verisimilitude in the case of opinion. And if likelihoods increase, they incline toward belief, faith being nothing other than an opinion supported by reason, iuvatarationibus.¹⁰⁰

Or, as he says elsewhere: firmata rationibus.¹⁰¹ As is clear, he mentions only reasons; everything is intellectual in this assent which Saint Thomas, after Aristotle, calls faith, and which is none other than the vehement opinion spoken of by Aristotle and Albert the Great, as Saint Thomas teaches us when he says: Credere dicimur quod vehementer opinamur.¹⁰²

Moreover, belief, however firm it may be, forever remains according to him an opinion. When Aristotle distinguished the virtues from opinion, he did not mention the latter among the intellectual virtues, i.e. habits that offer a guarantee of truth.¹⁰³ St. Thomas explains why: “What causes any sort of opinion to lean, even strongly, towards one side is not necessary and cannot give rise to a definitive judgment about the object.”¹⁰⁴ Despite its certainty, faith always includes the possibility of error.¹⁰⁵ Only, the chances of this possibility occurring are zero.

In short, firm and certain speculative belief occupies an intermediate place between science and common opinion. This is why St. Thomas allows us to understand vehement faith-opinion along the same lines of what Richard of Saint Victor perhaps applied to supernatural faith: infra scientiam, supra opinionem, below science but above opinion.¹⁰⁶ It has the speculative mode of science, but not the de iure certainty. But like opinion, it has the imposed contingency, though without its property: volitional fear. Firm belief constitutes a kind of transition species within the genus of assent, corresponding to what, in the genus of objective truth, is the transition species, the very probable, the ultimate disposition to the generation of evident truth, already having a given property of this form that is to come, namely, certitude (probabilissima, ultima dispositio ad generationem evidentis veritatis, iam proprietatem aliquam istius advenientis formae, certitudinem nempe, praehabens).

And so, at least in this first case of opinion, the alliance between probability and certainty is realized in the realm of pure speculation: Certitudo probabilis.

2. - Common assent of opinion.

Common opinion is that which is begotten in the speculative intellect by the experience of the ordinary probable.

Earlier above, we described the notion of the ordinary probable: that which is the verisimilar, that which positively draws close to the absolute truth. Opinion is neither doubt, nor the suspension of judgment, nor an abstract arbitration among supposedly opposing probabilities, but rather, an inclination of the intellect towards one side [of an issue] at the expense of the other, a true and positive assent.¹⁰⁷

The inclination of the common assent of opinion is so accentuated that Aristotle and St. Thomas did not hesitate to use the same name for it as they did for vehement opinion, the name reserved for firm belief, fides. Faith, says Aristotle, accompanies all opinion, for it is impossible for us not to believe what we have an opinion about.¹⁰⁸ And St. Thomas ups the ante: Every opinion is followed by faith, for everyone believes what he opines. But faith goes hand in hand with persuasion. Persuasion, in turn, logically requires¹⁰⁹ a reason. For there can be no persuasion without a rational motive.

Of course, this faith and reasoned persuasion do not confer a certificate of absolute infallibility on the opinion thus held to be true. Not only does the possibility of error remain, but since it is not controlled (as in the case of opinio vehemens) by experience of a probability so high that it touches on objective certainty and directly begets speculative conviction concerning its object, such common opinion therefore gives rise, according to the principles recognized above, to intervention by the will.¹¹⁰ This intervention manifests itself, as we have said, in the form of fears to the contrary, running counter to the assent of opinion.¹¹¹ And, as we shall now prove, it will also manifest itself in the form of resistance to these fears, and in the support lent to opinion in order maintain and strengthen it definitively in the direction of probability and, at last, to establish it as a probable certainty.

In the case of faith, Saint Thomas summarily described the mechanism by which the will intervenes in opinion. We have seen that the volitional movement we are discussing here is common to both faith and opinion.¹¹² Therefore, we can legitimately transpose to opinion what St. Thomas says about the common volitional intervention involved in faith.

Apart from the case of first principles and scientific conclusions, “the intellect,” he says, “is determined by the will. The will, by its choice, fixes the mind’s assent to one of the two sides present, inspired by a motive sufficient for putting the will into action, though of itself it does not suffice for moving the intellect, namely: it seems good and useful to give its assent to this side.”¹¹³

Let’s go back and now apply these data from Saint Thomas to opinion. This is the situation: the probable inclines the intellect to adhere. However, the latter is not mastered, as in the previous case. The possibility of error leaves room for thought, for cogitatio. Hence the appearance of fear or volitional apprehension in the person opining.

But, on the other hand, he realizes that, if the probable does not represent the absolute good for his intellect intelligence (i.e., the demonstrated truth), it nonetheless represents what directly leads to it, what, in certain obscure matters, necessarily replaces it. Therefore, if under the sway of fear, he were to refuse his assent, he would have to renounce the benefit offered by the preponderance of truth manifested in the probable; he would remain at zero while his objective rule marks perhaps 19 out of 20. Now, does this redound to the good of his mind? Does he not, rather, thereby cease hunting the prey because he has seen some mere shadow along the way? If, on the other hand, he commits his faith, then first of all, he commits no absurdity, for he realizes that certain matters do not lend themselves to more precise determinations and that, in scientific research, the period of discovery cannot provide the precision of fully constituted science. Therefore, if he adheres he will be doing something reasonable. What’s more, this act is advantageous precisely from the perspective of his mind’s own good, ruled as it is by the law of striving render itself equal to the true, meaning that assent to the plausible represents a state of mind well advanced in the pursuit of fulfilling this law. It is especially advantageous in scientific matters. Assent to the plausible (vraisemblable) provides solid footing, like a springboard from which we can launch onward towards what is even better, towards new progress. But, a springboard is only as good as its solid foundation. Therefore, the good of the mind requires that we hold the probable to be true, that we fix ourselves in adherence to the probable by means of a practically firm assent: “It is good and useful (for the mind) to give assent to the probable.”¹¹⁴ This is adequately reflected in the well-known practical rule: verisimilius est sequendum, plausible truths must be followed. This precept of intellectual conduct is of direct interest to the will, which depends on the good of the whole man, including his intellect. Therefore, it will assimilate it sympathetically, repressing fearful impulses at their very source; it will reflect its imperative strength upon the intellectual power, and the latter, executing what its object inclined the intellect itself to do, though without the object imposing this assent, will consent to the probable; it will have Probable Certainty.

In addition to these motives, drawn from the mind’s good, there are also motives drawn from the various ends of human life. Most of the time, the goods of all kinds that serve as the goal of our activity—individual goods of wealth or moral and even religious life, economic or social goods—are accessible to us only under the guise of probability. A great part of human activity depends on opinion-assent. Therefore, for the sake of the pursuit of our happiness, the need to attain these goods weighs heavily upon the intellect and demands the assent of firm opinion. How can we will and act if we do not believe, if our mind is not fixed on the immediate goals of action? Given that opinion is our ordinary lot in this order of things of such capital importance to us, it is good and useful, decens et utile, as Saint Thomas says, to commit one’s faith in opinion, to fix oneself by firm assent in the probable, to accept Probable Certainty.

Therefore, if we are not deluded by scope of our prior considerations, we can say: with this volitional concurrence actively taking part, the acquisition of a certainty that is objectively motivated by well-understood probability (in the sense of “probability” classically used in philosophy and not according to the sense of the term found in the works of modern probabilist moralists) is a legitimate thing and an acquired fact.¹¹⁵ All that remains is to analyze the characteristics of this certainty.

And first of all, this certainty is not speculative like that of absolutely firm belief. It is a practical certainty. But let us be clear about this word, “practical.”

As we have seen, the will’s motion upon the assent of opinion is not specifying, in contrast to the special motion of the will proper to faith. The probable is the light, the only light, of opinion as such: it specifies it directly as an intellectual act. Therefore, the role of the will can only be a kind of executive-moving role, first by excluding the volitional fear exercised against opinion (removens prohibens) then positively, by way of efficient causality, by categorically determining the exercise of the act, the assent of opinion. Thanks to this double intervention, the intellect elicits, or should I say executes, an act of adherence, one that surely is contingent, though sufficiently firm for its action to be engaged. The mind is practically fixed and certain.

But this practical certainty itself can be of two kinds.

As we have said, the motives of the will are two in kind: the good of the mind itself; and the general ends of human life.

If the will is set in motion (as it is in scientific research, in questions of fact, etc.) by the desire to ensure the good of the mind, that is, in the absence of the absolute truth which is not found in the given circumstances, the possession of this predominant acquisition of objective truth contained in the probable, the motion exercised belongs to the physical—or better to the psychological—dynamics of the human intellect, which in the concrete order is the faculty of a human subject, which the will is also. The principle Verisimilius est sequendum, which is its immediate guiding principle is inspired only by the necessities of the mind. In such a case, practical certainty does not mean certainty concerning a practical matter, but only certainty obtained through an action (πρᾶξις) of the will, acting moreover for a speculative purpose.

By contrast, if the will is set in motion by the interest that arises from the experience of whatever goods the opinion is concerned with, the certainty resulting from the will’s intervention is said to be practical in a new respect, namely due to the influence exerted on the will by ends essentially intended to provoke in relation to them the action, πρᾶξις , of the will and of the executive powers. The mind’s certainty serves the volitional intention of these ends; it is, therefore, ordered to their satisfaction. Hence, its goal is no longer simply, as before, to firmly ensure, within the mind, the relative adequation of intellect to the being authorized by the probable, even though this goal is not excluded and is, in fact, the sine qua non condition for obtaining the ulterior goal;¹¹⁶ its purpose is, in addition, to ensure that the will has firm knowledge of the means suitable for realizing the ends of the will. The value of the opinion rendered certain by such a motion consists not only in its conformity with its direct object but also in its conformity with the appetite for the ends of human life.

From this follows an important consequence for the formation of certainty of opinion in practical matters. Allow me to quote myself from an earlier work:¹¹⁷ When faced with a statement that concerns action, the mind does not act in isolation. Whenever the truth in question is the good, the whole of man is on the lookout. Abstractly considered, such influences tergo, from behind, are bad laborers in the service of the truth. However, there are cases when, to the contrary, their action is conducive to the strengthening of true knowledge. For example, if I am hesitating about the moral truth of a statement, nothing can make it easier for me to see what’s true than the prior rectitude of my state of mind with regard to the certain principles of morality. The habit of honest, hatred of falsehood, the stripping away of illusory ends, and the love of true ends—in short, in St. Thomas’ evocative expression, veritas vitae—are all moral dispositions whose after-effects are felt in the truly moral object and exalt its ability to be accepted as such by the mind. Thus, we here have reinforcement for probability in moral matters which, for an intellect used by the will for the will’s own ends, must lead to reinforcements for one’s adherence [to the truth].

Clearly, these moral reinforcements, which so often are decisive, cannot totally replace the objective light of the probable argument that presents the object. Undoubtedly, in itself, the good coincides with the true, but if we content ourselves to solely be led by the light of our intentions, we could very well deceive ourselves. As we have said, the role of these volitional supplements is executive-moving one: they reinforce the influence of the probable, but never do they totally supplant it. It would be a mistake to assign to them the scope of a precise criterion for assessing probability. They only attain the object insofar as its content is in harmony with the true ends of human life, lived and active in the moral man—with man’s true morals.¹¹⁸

Epilogue: Moral Certainty.

These considerations lead us straight to the understanding of a notion whose name we have not yet pronounced, because we were reserving it for the end, though, perhaps, it has presented itself many times to the mind of our reader in the course of this study. I mean, of course, Moral Certainty. What is the relationship between the probable certainty spoken of by Saint Thomas¹¹⁹ and the moral certainty spoken of in the modern age?

This relationship is not simple, because the word moral has two meanings, both of which are relevant to our subject.

“This noun, moral, comes etymologically from the word custom, affected by slight variations. For in Greek ethos, when written with the short epislon, ε, (ἔθος), means morals, moral virtue. Written with the long eta, η, it means custom (ἦθος). Thus, today, by the word, moral, we sometimes today sometimes custom and sometimes what has to do with vice and virtue.”¹²⁰

“The word mos has two meanings. Sometimes, it means what is customary, as in this text from Acts 15: Unless you are acircumcised according to the custom, morem, of Moses, you cannot be saved. But sometimes it signifies a natural or quasi-natural inclination to a given action: this is the sense in which we speak of the morals of animals, as in this text from Macabees: Leonum more irruentes in hostes prostraverunt eos, charging like lions into the enemies, they overthrew them. And this is how the word mos is understood from Psalm 67: qui habitare facis unius moris in domo, you who make men of one manner to dwell in a house… In this way, moral virtue is denominated from the word mos, understood in the sense of a natural or quasi-natural inclination to action. And this meaning is very close to the other, for custom also changes into nature and produces inclinations similar to natural inclinations.”¹²¹

Therefore, the word moral means: 1˚ that which is customary, ordinary, and habitual; 2˚ that which derives from a natural principle, from a habit, from the morals of a subject, whether natural or acquired; and 3˚ in this second case, it takes on a more precise meaning whenever good or bad habits are involved.

It is not difficult to fit these notions into one or the other of the modalities of probable certainty.

1˚ The probable certainty of firm speculative belief, or vehement opinion, is not a merely customary, habitual certainty, whose value would be founded on the ordinary success (ut in pluribus) of its claims to truth. It is something more than that. Without being de iure certainty, it is a certainty founded on our natural speculative inclination towards the truth. Where does the exercise of this inclination come from? From the speculative value of probabilissima—from its unparalleled probability, to the point that it is akin to absolute truth. The probability of the object of firm belief, fides, is, in fact, the immediate prelude to truth, its maximal approximation, its ultimate prior disposition (ultima dispositio praevia), its property announcing in advance the essence from which it emanates: absolute evidence. Therefore, in this first case, probable certainty is moral certainty, in the sense of certainty begotten by what we might call the mores of the speculative mind, which are summed up in its intrinsic tendency towards absolute truth.

2˚ In common opinion—if we consider only its speculative productive-factor—probable certainty coincides with moral certainty, in the sense of true, customary, and habitual ordinary certainty. The probable, verum ut in pluribus, cannot communicate more to the mind. It begets neither scientific evidence nor the firmness of belief. But let us not say that it has no certainty. Certitudo scientiae consistit in duobus, scilicet in evidentia et firmitate adhaesionis; certitudo autem fidei consistit in uno tantum, scilicet in firmitate adhaesionis. Certitudo vero opinionis in neutro.¹²² The certainty of science consists of two things, namely evidence and firmness of adherence; the certainty of faith, however, consists of only one, namely firmness of adherence. But, the certainty of opinion consists of neither.

However, as we have said, this certainty leaves room for volitional intervention. And, from then on, it is susceptible to extrinsic strengthening, which will enable it to claim, on new grounds—practical ones, that is—the title of moral certainty.

3˚ If common opinion is conceived under the influence of the will as the provider of the intellect’s good, its intrinsic certainty is related to the fundamental inclination of the will toward the good of man in general. Now, this inclination of the will is an inclination of nature. The probable certainty of opinion will therefore be called moral certainty in the second sense of the word moral. In other words, it is according to man’s mores. And this is why, in practice, every man is naturally the believer of his opinions. Opinionem sequitur fides et persuasio.¹²³ His will, naturally interested in the good of his mind as well as the good of all the rest of his faculties, inclines him to hold as true in practice what he believes to be true, even though absolute proof is lacking. This is a universally experienced fact.

4˚ If common opinion is considered under the influence of the willing of the natural ends of human life, it receives from this contact an additional practically-practical certainty which is added to the intrinsic speculative certainty of opinion and to the speculatively-practical certainty we were been talking about. This is the case with those beliefs that are so firm as to be absolutely at placidly held, the ineradicable beliefs of mankind. The certainty thus obtained, while remaining probable certainty (because of the immediate object of the mind’s adherence) is moral certainty at its most firm. It is at one with the mores of humanity.

5˚ Finally, if common opinion is considered under the influence of the willing of rational ends, the same law of practical reinforcement of its certainty follows its course. But the certainty thus obtained will be said to be moral in a very special sense.¹²⁴ Mores proprie dicuntur humani, says Saint Ambrose, approved by Saint Thomas.¹²⁵ The word moral, in this case, does not refer to just any old human mores, but rather, to the very principle of human mores truly worthy of the name—to reason, the faculty of supreme ends that constitute the specifically human Ideal. Through the intermediary of the will that is rectified in relation to this ideal, something of the inclination to the Good, which constitutes the fundamental mores of the honest man, is as it were diffused into the intellect and enables it to adhere with strong certainty to contingent objects in harmony with man’s true good. This certainty remains probable, in view of its objective reasons; but its firmness is moral, given that it is produced by the morality of the subject who possesses it. Such certainty is surely legitimate, since the Good coincides in itself with the true [sic], having arisen from the same primary source. However, as our moral instincts can err in their estimation of true contingent goods, these moral reinforcements must never replace the intrinsic criterion of moral truth.¹²⁶ Their role will remain that of an auxiliary support to the assent of opinion. Within these limits, we can speak of moral probable certainty and moral probabilism, as well as moral dogmatism—but only within these limits.

6˚ The moral ideal in its highest expression is God; human morality pushed to its ultimate end is necessarily religious. Now, it is to be expected that God actively watches over those acts which ultimately lead to the extension of His reign. Probable certainty in moral and religious matters marks a moment in our orientation towards God. From a purely philosophical perspective, we can therefore admit that God himself intervenes to ensure that our contingent certainties correspond to the moral and religious Ideal they are intended to serve. And when He does, the assurance of our opinions, without speculatively departing from the order of probable certainty, will become practically absolute. This is supernatural moral certainty. This is what led the author of the Eudemian Ethics to say the words so often quoted by Saint Thomas: His qui moventur per instinctum divinum non expedit consiliari secundum rationem humanam, sed quod sequantur interiorem instinctum ; quia moventur a meliori principio quam sit ratio humana. It is not expedient for those who are moved by divine instinct to follow human reasoning; rather, they should follow their inner instinct, for they are moved by a better principle than human reason.¹²⁷

***

And now we can answer the question that prompted this study. No, certainty is not opposed to probability. On the contrary, any rigorous understanding of the certainty that is nowadays accepted—by all philosophers worthy of the name and by theologians without exception—under the name of moral certainty is only possible if, having examined the two terms of the antithesis, certainty and probability, one knows how to balance them in a measured way and weld them together into Saint Thomas’s unique expression, which is paradoxical only in appearance: Certitudo probabilis.

Fr. A. Gardeil, O.P.

Le Saulchoir, Kain.

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1. Thus, Saint Thomas concludes that, since the object of faith is a proposition, the act of faith is a judgment and an assent, not an intuition. See In III Sent., dist. 23, q. 2, a. 2, sol. 1.↩︎

2. Translator’s note: Note, therefore, the distinction between a complex statement and the judgment related to it.↩︎

3. See the paragraph starting “It is from this particular angle of methodological logic that I would like to take up the question” in the first part of this article.↩︎

4. Translator’s note: In this second article, I will mostly translate variables on vraisemblable using expressions related to “likely”. On several occasions in the previous article, I used “verisimilar” (sometimes with accompanying paralellisms in apposition), due to certain etymological points Fr. Gardeil made regarding “similarity to the truth”.↩︎

5. See the section “The Real Definition of the Probable” in the first part of this article.↩︎

6. See the paragraph starting “To adhere: but to what?” in the first part of this article.↩︎

7. See De veritate, q. 14, a. 1.↩︎

8. Ibid. See ST I–II, q. 67, a. 3.↩︎

9. In III De Anima, lect. 4.↩︎

10. See In IV Ethic, lect. 8.↩︎

11. See ibid.↩︎

12. See ST II-II, q. 1, a. 4.↩︎

13. See ST I, q. 79, q. 9, a. 3: “However, (the intellect) imperfectly knows contingent things, just as they themselves have imperfect being [esse] and truth.”↩︎

14. ST II-II, q. 1, a. 5, ad 4.↩︎

15. The texts published prior to the Leonine edition had id quod est opinatum instead of id quod quis existimat. The opposition of the two estimates in opposite directions was less pronounced and less actual.↩︎

16. See In III De Anima, lect. 5: “Someone rids himself of a true opinion in three ways: first, when realities change... Second, when he has forgotten the former opinion; and third, when he no longer believes what he previously believed, having changed due some other reason [having come to light]."↩︎

17. See In Boet., de Trin., q. 3, a. 1, ad 4: “Although a demonstration [strictly so called] never concludes at something false, nonetheless man falls short therein because he believes that something is a demonstration when, in fact, it is not.↩︎

18. See De Malo, q. 16, a. 6: “A false opinion is a kind of defective operation by the intellect just as a monstrous birth is a kind of defective operation of the soul… However, a defective operation always proceeds from the defect in some principle, just a birth defect proceeds from some defect in the seed. Hence, it is necessary that a false estimation proceeds from a defect in some cognitional principle.”↩︎

19. It is in this sense that the Dialecticians discuss what they call opinions, i.e. statements that are often false in themselves but which have received the assent of others: “This does not hold: ‘The assent is certain, therefore it is true,’ although in our days among dialecticians it is considered good... Hence Aristotle, in Nicomachean Ethics 7.3 says: ‘some assent to their false opinions no less than others do to their scientific knowledge.’ And Aristotle would have referred to those false assents as faith (Soto, loc. cit. p. 127 recto, col. 2)↩︎

20. See Ambroise Gardeil, “La notion du Lieu théologique,” RSPT 2 (1908): 55–56 (pages 10–11 in the Gabalda offprint edition).↩︎

21. In III Sent., dist. 23, q. 2, a. 2, sol. I.↩︎

22. De Veritate, q. 14, a. 1.↩︎

23. ST II-II, q. 1, a. 4.↩︎

24. ST II-II, q. 2, a. 9.↩︎

25. In Boetium de Trin., q. 3, a. 1.↩︎

26. In III Sent., dist. 23, q. 2, a. 2, sol. 1.↩︎

27. Ibid.↩︎

28. See Avicenna, Metaph, bk. 2, ch. 4 and bk. 8, ch. 6.↩︎

29. In III Sent., dist. 23, q. 2, a. 2, sol. 1.—De Veritate, q. 14, a. 1, in fine.↩︎

30. Those who invoke the quoted text (De ratione opinionis est quod accipiatur unum cum formidine alterius) in order to thereby to make volitional fear an intrinsic element of opinion fail to take into account the fact that the word cum does not necessarily designate an intrinsic element. The definition holds, even though formido is an extrinsic property, provided that, by its nature, it is attached to the essence. See “§3 The Property of Opinion: formido errandi” below.↩︎

31. In III Sent., dist. 23, q. 2, a. 2, sol. 1.↩︎

32. De Veritate, q. 14, a. 1.↩︎

33. ST II-II, q. 2, a. 9.↩︎

34. ST II-II, q. 2, a. 1 - In III Sent., d. 23, q. 2, a. 2, sol. 1, in fine.↩︎

35. In III Sent. dist. 23, q. 2, a. 2, sol. 3, ad 2. This is discussing supernatural faith.↩︎

36. In Boetium. De Trin., q. 3, a. 1.↩︎

37. De Veritate, q. 14, a. 1, in fine.↩︎

38. In III Sent. dist. 23, q. 2, a. 2, sol. 1.↩︎

39. Ibid.↩︎

40. ST II-II, q. 1, a. 4.↩︎

41. In Sent. loc. cit. a. 1.↩︎

42. De Veritate, q. 14, a. 1.↩︎

43. In Boetium. De Trin., q. 3, a. 1↩︎

44. De Veritate, q. 14, a. 1↩︎

45. ST I-II, q. 55, a. 4c.↩︎

46. ST I-II, q. 55, a. 4c.↩︎

47. ST I-II, q. 57, a. 2, ad 3.↩︎

48. De Veritate, q. 14, a. 8, c.↩︎

49. In VI Ethic, lect. 3.↩︎

50. De Verit., q. 14, a. 1.—Discursive thought, cogitatio, which is the mode of knowledge characteristic of the act of opining, belongs de iure to the particular, or cogitative, reason—pars opinativa—an internal sense faculty according to Aristotle and Saint Thomas, though, in man, situated on the very borders of the intellectual faculty. See In III Sent. dist. 23, q. 2, a. 2, sol. 1, ad 3. Precisely because of this affinity, this mode of knowledge has been transposed to the intellectual part and designates there the act we commonly refer to as thought. (Ibid. and De Veritate, q. 14, a. 1, ad 9)↩︎

51. De Veritate, q. 14, a. 4; In III Sent., dist. 23, q. 2, a. 3, sol. 2.—This state of the intellect, thus moved by the will, should not be confused with practical reason. See ibid., ad 3 and De Veritate ibidem.↩︎

52. See De Virtutibus, q. 1, a. 7.↩︎

53. Materialiter intellectus, formaliter voluntatis, if we consider as formal principle that which is the principle actively determining the specification. Formaliter intellectus, praesupposito actu voluntatis, if we are considering the specifying object of the act of faith, an object that is, as it were, its form.↩︎

54. ST II-II, q. 1, a. 4.↩︎

55. ST I-II, q. 17, a. 6.↩︎

56. We are tempted to counterbalance this with the text from the Philosopher: “It is within our power to imagine, whenever we wish... Having an opinion does not depend on us. It must, in fact, declare truth or falsehood” (De Anima, 3.3; St. Thomas, lect. 4). However, as St. Thomas observes, this passage simply establishes that the person who utters an opinion does not do so without an objective motive, which is the cause of its truth. By contrast, we can arbitrarily imagine “golden mountains.” And this suffices for distinguishing opinion from imagination, though not enough to exclude the intervention of a will choosing between the options presented to it, though without arbitrariness, in virtue of certain reasonable motives which are, otherwise, non-necessary.

    A text that at first glance seems more affirmative against volitional intervention is this one: “Science and opinion are not influenced by the will, but by reason alone” (De Veritate, q. 14, a. 3, ad 5). However, if we compare this with the objection to which Saint Thomas is responding, and with the context, we realize that the absence of volitional influence referred to is the absence of an absolutely necessary volitional intervention. The exercise of the perfect virtues, those that not only give the ability to act well, but to act well effectively (that is, right use), absolutely requires this intervention. Volitional rectification is essential to these virtues, and necessarily prerequisite for them to operate in this way. Science, which only provides the power to think well, not to act, and a fortiori opinion, do not require this volitional intervention: in the case of science because, given its self-sufficiency, it admits of no other intervention by the will than that which moves it to exercise it; and in that of opinion, because it is not an intellectual virtue, given its ability to be false. The fact remains, however, that, without requiring the will for its proper use, opinion nonetheless can appeal to it in order to put an end to the indeterminacy that it always seems to have to maintain from a purely intellectual perspective—and this is what Saint Thomas seems to be saying in the passage from the Summa quoted above.↩︎

57. De Soto, In Dial. Arist., Posteriorum, bk. 1, q. 8 (§ Quaestio haec, - Resp. ad arg.), 1554 edition, p. 127 verso, col. 1.↩︎

58. Ibid., resp. ad 2.↩︎

59. The will is not, in the proper sense, a natural appetite, appetitus naturalis, immanent to any tendency of nature, immanent, for example, to the intellect’s tendency toward truth and of heavy bodies to fall vertically. It is an animal appetite, i.e. a function of the whole living being, dependent on everything of concern (in whatever capacity, partial or total) for the good of the living being. See ST I, q. 80, a. 1, with no. 3 of Cajetan’s commentary.↩︎

60. See In III De Anima, lect. 4 (versio antiqua): “For this passion (phantasia) exists in us when we so wish... However, to hold an opinion is not within the ambit of our control. It is necessary to speak either falsely or truly.”↩︎

61. Ibid.↩︎

62. For the meaning of these expressions, see St. Thomas’s commentary In I Posterior Analytics, lect. 10.—Cf. Soto, Op. cit. ch. 4 (De modis per se, p. 91).↩︎

63. See De virtutibus, q. 1, a. 7c: “The will commands [imperat] the intellect not only as regards the performance of its act but also as regards the determination of its object, for at the will’s command (imperio), the intellect assents to a determinate belief.”↩︎

64. See Soto, In I Poster, q. 8, ed. cit., p. 127, verso, col. 1 and 2.↩︎

65. See Ambroise Gardeil, La Crédibilité et apologétique (1908 ed.), p. 97.↩︎

66. Translator’s note: He is here referring to the general principles used in the casuist tradition for steadying one’s judgment in difficult matters. (And, as I have argued elsewhere, e.g., in my introduction to Conscience: Four Thomistic Treatments, there are also no doubt more specific principles. I say this in view to even what Beaudouin says in the De conscientia edited by Gardeil. See also my treatment there concerning the role of appetite in practical reasoning. Also, see his essay on infused prudence in The True Christian Life.↩︎

67. See De Veritate, q. 14, a. 2, ad 10. See, in the body of the article: “However, the will, moved by the aforementioned good, proposes to the intellect something that does not appear as worthy of assent, and thus it determines the intellect towards that non-apparent thing, so that it may assent to it.”↩︎

68. In III Sent., dist. 24, q. 1, a. 2, sol. 1: “God evades what our intellect can form and is not penetrable [pervius] to it while we are wayfarers”↩︎

69. See Soto, Loc. cit. p. 127 recto, col. 2: “As St. Thomas excellently noted, Aristotle uses the term opinion to refer to any human belief”↩︎

70. See Ch. and V. Mortet, “Histoire” in Grande Encyclopédie, vol. 20, p. 142.↩︎

71. That is, plausible, worthy of approval. In the previous article, see the discussion starting with the paragraph “The currently reigning opinion…” and “To adhere: but to what?”↩︎

72. In III Sent. dist. 24, q. 1, a. 3, sol. 2, ad 1.↩︎

73. De Veritate, q. 14, a. 3, ad 8.↩︎

74. In Sent. loc. cit. sol. 1, c.↩︎

75. De Veritate, q. 14, a. 3, ad 8.↩︎

76. De Veritate, q. 14, a. 8, ad 2 and ad 9.↩︎

77. In III Sent. dist. 23, q. 2, a. 4, ad 2.↩︎

78. See [First] Vatican Council, Dei filiusch. 3 (Denzinger, no. 3008 [1789]).↩︎

79. ST II-II, q. 109 and 110; See Schwalm, Aux Sources de l'Activité intégrale, I. Sincérité (Paris: Lethielleux, 1911), 5, 20, 27, 33.↩︎

80. In Boetium. De Trin., q. 3, a. 1: “And because amid the social life of men one man must, in those matters wherein he does not suffice for himself, make use of another as he makes use of himself, therefore, it is necessary that he rely on what another person knows as regards matters that he himself does not know, just as in those things that he knows by himself. Consequently, in human intercourse, faith is necessary.”↩︎

81. In III Sent., dist. 23, q. 2, a. 2, sol. 2.↩︎

82. De Soto, In Dial. Arist. poster, ed. cit. bk. 1, q. 8 (p. 128 recto, col. 2);↩︎

83. Ibid., col. 1.↩︎

84. Ibid.↩︎

85. Ibid. p. 127, verso, col. 2: “Hence, Aristotle would not have denied that a movement of the will is required for faith and opinion, but however, he only dealt with the principles of habits that are in the intellect, that is with propositions and terms from which reasoning is constructed.”↩︎

86. ibid. (p. 128, recto, col. 1).↩︎

87. ibid. (p. 127, verso, col. 1).↩︎

88. ibid. col. 2.↩︎

89. ibid. (p. 128, recto, col. 1).↩︎

90. See the example cited by Saint Thomas in ST I-II, q. 111, a. 1, ad 3. Another example of this is when we use the word animal to designate all animals except man.↩︎

91. See the section “I. The will’s intervention in opinion” above.↩︎

92. See In III De anima, lect. 4 (§ amplius autem).↩︎

93. Marie-Benoît Schwalm, “La Croyance naturelle et la Science,” Revue Thomiste 5 (1897): 640.↩︎

94. Pascal, Pensées, ed. Brunschvicg, p. 425.↩︎

95. See the section “I. The will’s intervention in opinion” above.↩︎

96. De Soto, In Dial. Arist. poster, bk. 1, q. 8 (p. 127, verso col. 1).↩︎

97. Ibid. col. 2.↩︎

98. Albert the Great describes with great depth the twofold character of this kind of belief: “Of itself, opinion is not certain, though it becomes certain to those to whom it seems and appears so; and it is not certain except insofar as such an opinion concerning an immediate proposition (an analytic principle [per se nota]) falls upon it, because in this way it is known [scitum], although it is not accepted in the manner of science. Thus, to know [scire] is said to to opine strongly…” (Poster, bk. 1, tr. 5, ch. 9 [Vivès, vol. 2], p. 150–151).↩︎

99. Augustine, De Trinitate, bk. 13, ch. 5 (Cf. ST I-II, q. 5, a. 8).↩︎

100. In Boetium De Trinitate, q. 3, a. 1, ad 4.↩︎

101. In III Sent. dist. 23, q. 2, a. 2, sol. 3 ad 1.↩︎

102. De Veritate q. 14, a. 2, § 2. Cf. Aristotle, Topics, 1.5.↩︎

103. Aristotle, Nicomachean Ethics, 6.2–3 and Thomas’s commentary, lect. 2 and 3.↩︎

104. In Boetium De Trinitate., q. 3, a. 1 and 4.↩︎

105. ST II-II, q. 4, a. 5, ad 2.↩︎

106. In III Sent., dist. 23, q. 2, a. 2, sol. 2, ad 2.↩︎

107. See the sections “The influence of verisimilitude of the probable on opinion” as well as the textual study of Thomas concerning these matters.↩︎

108. See Aristotle, De Anima, 3.4.↩︎

109. “According to the order of inference. (Secundum ordinem illationis.)” Ibid. lect. 5 (§Amplius omnem)↩︎

110. See the section “The Will’s Intervention in faith and opinion” above. Cf. ST II-II, q. 1, a. 4.↩︎

111. See the discussion starting with “But we can also consider opinion as constituting a genus” above.↩︎

112. See the section “The Will’s Intervention in faith and opinion” above.↩︎

113. De veritate, q. 14, a. 1.↩︎

114. Cf. text quoted on previous page.↩︎

115. Once we have seen the theory, it is very interesting to see how it is put into practice. Saint Thomas gives us a curious application in ST II-II, q. 70, which I mentioned earlier as the topical locus of probable certainty.

     This question is concerned with how to establish the legitimacy and conditions of legal testimony. By the testimony of two or three witnesses, the fact of a crime is rendered only probable. But the judge's sentence can only be absolute. How can it be based on probability? Such is the problem.

     Saint Thomas responds by invoking three orders of considerations. 1° There is intrinsic value of the probable, which is sufficient in itself to motivate opinion in contingent matters. In actibus enim humanis non potest haberi certitudo demonstrativa... Et ideo sufficit probabilis certitudo quae ut in pluribus veritatem attingat (a. 2, in corp). These last words declare the speculative foundationof opinion: the probable is an approximation to the truth. 2° To this speculative value is added a practical value: non debet negligi probabilis certitudo quae probabiliter haberi potest per testes (ibid., ad 1). Non debet, must not, is a guiding principle for action. What is its basis? The good of the intelligence, which finds in the probable the truth as much as it can require in such matters: Certitudo non est similiter quaerenda (another practical principle) in omni materia, certainty must not be sought in the same way in all manners. 3° Finally, in addition to the first two motives, the social good intervenes: it is necessary that justice be done. To refuse to decide between the plaintiff and the defendant, between society and the accused, when there is evidence at hand, as much as can be asked for in such matters, would indeed be as unjust as to judge arbitrarily, since someone will certainly be harmed. Taking note of this social necessity for which the law is responsible, and also considering the rational good represented by the probable, the Law awards the legitimacy of probable certainty. Rationabiliter institutum est de jure divino et humano quod dicto testium stetur (ibid). The judge, under the pressure of these three certainties—the speculative certainty of the probable, its practical certainty as the good of the mind, and its practical certainty as the good of human society—pronounces his judgment. In other words, in virtue of these three titles, probable certainty has the absolute legitimacy of the most categorical action possible. Indeed, it may well be a question of sending a man to his death.

     This same theme, less developed but perhaps more expressive, can be found in St. Thomas’s commentary on the words of St. John's Gospel, “The Testimony of two men is true”: "One must understand that what is considered true in judgment must be regarded as true. This is because true certainty cannot be obtained in human actions; therefore, what can be considered more certain, which is through a multitude of witnesses, is accepted [as true]. For it is more probable that one person would lie than many” (S. Thomas, In VIII Joannis evang. lect. 2, no. 8, edit. Parma, vol. 10, p. 445).↩︎

116. The instrument serves the intentions of the principal cause that uses it only by normally performing its act, in this case assenting to the probable in proportion to its supporting motives.↩︎

117. Cf. Gardeil, La Crédibilité et l'Apologétique, 1^st ed. passim, p.102ff. The present study was inspired by the desire to give a developed theoretical basis to certain notions I have set out in this work, and thus to prepare for the reworked edition that will appear at the end of 1911.↩︎

118. Cf. La Crédibilité et l'Apologétique (1^st ed.), ibid.↩︎

119. I am not aware of anywhere that St. Thomas ever utters the word moral certainty.↩︎

120. In II Ethic., lect. 1.↩︎

121. ST I-II, q. 58, a. 1.↩︎

122. In III Sent., dist. 23, q. 2, a. 2, sol. 3, ad 1.↩︎

123. See In III De Anima, lect 5, quoted above in the paragraph starting “The inclination of the common assent of opinion…”↩︎

124. The third sense of the word moral.↩︎

125. See ST I-II, q. 1, a. 3.↩︎

126. See La Crédibilité et l'Apologétique (1^st ed.), 102ff, especially p. 106.↩︎

127. ST I-II, q. 68, a. 1.↩︎