Thomas Aquinas, Summa Theologiae

Objection 1: It would seem that faith is not more certain than science and the other intellectual virtues. For doubt is opposed to certitude, wherefore a thing would seem to be the more certain, through being less doubtful, just as a thing is the whiter, the less it has of an admixture of black. Now understanding, science and also wisdom are free of any doubt about their objects; whereas the believer may sometimes suffer a movement of doubt, and doubt about matters of faith. Therefore faith is no more certain than the intellectual virtues.

Objection 2: Further, sight is more certain than hearing. But "faith is through hearing" according to Rm. 10:17; whereas understanding, science and wisdom imply some kind of intellectual sight. Therefore science and understanding are more certain than faith.

Further, in matters concerning the intellect, the more perfect is the more certain. Now understanding is more perfect than faith, since faith is the way to understanding, according to another version of Is. 7:9: "If you will not believe, you shall not understand ": and Augustine says (De Trin. xiv, 1) that "faith is strengthened by science." Therefore it seems that science or understanding is more certain than faith.

On the contrary, The Apostle says (1 Thess. 2:15): "When you had received of us the word of the hearing," i.e. by faith . . . "you received it not as the word of men, but, as it is indeed, the word of God." Now nothing is more certain than the word of God. Therefore science is not more certain than faith; nor is anything else.

I answer that, As stated above (1.2, Question 57, Article 4, ad 2) two of the intellectual virtues are about contingent matter, viz. prudence and art; to which faith is preferable in point of certitude, by reason of its matter, since it is about eternal things, which never change, whereas the other three intellectual virtues, viz. wisdom, science and understanding, are about necessary things, as stated above (1.2, Question 57, Article 5, ad 3). But it must be observed that wisdom, science and understanding may be taken in two ways: first, as intellectual virtues, according to the Philosopher (Ethic. vi, 2,3); secondly, for the gifts of the Holy Ghost. If we consider them in the first way, we must note that certitude can be looked at in two ways. First, on the part of its cause, and thus a thing which has a more certain cause, is itself more certain. In this way faith is more certain than those three virtues, because it is founded on the Divine truth, whereas the aforesaid three virtues are based on human reason. Secondly, certitude may be considered on the part of the subject, and thus the more a man's intellect lays hold of a thing, the more certain it is. In this way, faith is less certain, because matters of faith are above the human intellect, whereas the objects of the aforesaid three virtues are not. Since, however, a thing is judged simply with regard to its cause, but relatively, with respect to a disposition on the part of the subject, it follows that faith is more certain simply, while the others are more certain relatively, i.e. for us. Likewise if these three be taken as gifts received in this present life, they are related to faith as to their principle which they presuppose: so that again, in this way, faith is more certain.

Reply to Objection 1: This doubt is not on the side of the cause of faith, but on our side, in so far as we do not fully grasp matters of faith with our intellect.

Reply to Objection 2: Other things being equal sight is more certain than hearing; but if (the authority of) the person from whom we hear greatly surpasses that of the seer's sight, hearing is more certain than sight: thus a man of little science is more certain about what he hears on the authority of an expert in science, than about what is apparent to him according to his own reason: and much more is a man certain about what he hears from God, Who cannot be deceived, than about what he sees with his own reason, which can be mistaken.

Reply to Objection 3: The gifts of understanding and knowledge are more perfect than the knowledge of faith in the point of their greater clearness, but not in regard to more certain adhesion: because the whole certitude of the gifts of understanding and knowledge, arises from the certitude of faith, even as the certitude of the knowledge of conclusions arises from the certitude of premisses. But in so far as science, wisdom and understanding are intellectual virtues, they are based upon the natural light of reason, which falls short of the certitude of God's word, on which faith is founded.

Articulus 8

Argumentum 1

Ad octavum sic proceditur. Videtur quod fides non sit certior scientia et aliis virtutibus intellectualibus. Dubitatio enim opponitur certitudini, unde videtur illud esse certius quod minus potest habere de dubitatione; sicut est albius quod est nigro impermixtius. Sed intellectus et scientia, et etiam sapientia, non habent dubitationem circa ea quorum sunt, credens autem interdum potest pati motum dubitationis et dubitare de his quae sunt fidei. Ergo fides non est certior virtutibus intellectualibus.

Argumentum 2

Praeterea, visio est certior auditu.

Sed fides est ex auditu, ut dicitur ad Rom. X, in intellectu autem et scientia et sapientia includitur quaedam intellectualis visio.

Ergo certior est scientia vel intellectus quam fides.

Argumentum 3

Praeterea, quanto aliquid est perfectius in his quae ad intellectum pertinent, tanto est certius. Sed intellectus est perfectior fide, quia per fidem ad intellectum pervenitur, secundum illud Isaiae VII, nisi credideritis, non intelligetis, secundum aliam litteram. Et Augustinus dicit etiam de scientia, XIV de Trin., quod per scientiam roboratur fides.

Ergo videtur quod certior sit scientia vel intellectus quam fides.

Sed Contra

Sed contra est quod apostolus dicit, I ad Thess. II, cum accepissetis a nobis verbum auditus, scilicet per fidem, accepistis illud non ut verbum hominum, sed, sicut vere est, verbum dei.

Sed nihil certius verbo dei.

Ergo scientia non est certior fide, nec aliquid aliud.

Corpus

Respondeo dicendum quod, sicut supra dictum est, virtutum intellectualium duae sunt circa contingentia, scilicet prudentia et ars. Quibus praefertur fides in certitudine, ratione suae materiae, quia est de aeternis, quae non contingit aliter se habere. Tres autem reliquae intellectuales virtutes, scilicet sapientia, scientia et intellectus, sunt de necessariis, ut supra dictum est.

Sed sciendum est quod sapientia, scientia et intellectus dupliciter dicuntur, uno modo, secundum quod ponuntur virtutes intellectuales a philosopho, in VI ethic.; alio modo, secundum quod ponuntur dona spiritus sancti.

Primo igitur modo, dicendum est quod certitudo potest considerari dupliciter. Uno modo, ex causa certitudinis, et sic dicitur esse certius illud quod habet certiorem causam. Et hoc modo fides est certior tribus praedictis, quia fides innititur veritati divinae, tria autem praedicta innituntur rationi humanae. Alio modo potest considerari certitudo ex parte subiecti, et sic dicitur esse certius quod plenius consequitur intellectus hominis. Et per hunc modum, quia ea quae sunt fidei sunt supra intellectum hominis, non autem ea quae subsunt tribus praedictis, ideo ex hac parte fides est minus certa. Sed quia unumquodque iudicatur simpliciter quidem secundum causam suam; secundum autem dispositionem quae est ex parte subiecti iudicatur secundum quid, inde est quod fides est simpliciter certior, sed alia sunt certiora secundum quid, scilicet quoad nos. Similiter etiam, si accipiantur tria praedicta secundum quod sunt dona praesentis vitae, comparantur ad fidem sicut ad principium quod praesupponunt. Unde etiam secundum hoc fides est eis certior.

Ad 1

Ad primum ergo dicendum quod illa dubitatio non est ex parte causae fidei, sed quoad nos, inquantum non plene assequimur per intellectum ea quae sunt fidei.

Ad 2

Ad secundum dicendum quod, ceteris paribus, visio est certior auditu. Sed si ille a quo auditur multum excedit visum videntis, sic certior est auditus quam visus. Sicut aliquis parvae scientiae magis certificatur de eo quod audit ab aliquo scientissimo quam de eo quod sibi secundum suam rationem videtur. Et multo magis homo certior est de eo quod audit a deo, qui falli non potest, quam de eo quod videt propria ratione, quae falli potest.

Ad 3

Ad tertium dicendum quod perfectio intellectus et scientiae excedit cognitionem fidei quantum ad maiorem manifestationem, non tamen quantum ad certiorem inhaesionem. Quia tota certitudo intellectus vel scientiae secundum quod sunt dona, procedit a certitudine fidei, sicut certitudo cognitionis conclusionum procedit ex certitudine principiorum. Secundum autem quod scientia et sapientia et intellectus sunt virtutes intellectuales, innituntur naturali lumini rationis, quod deficit a certitudine verbi dei, cui innititur fides.