Thomas Aquinas, Summa Theologiae

Objection 1: It would seem that the same passions are in the irascible and concupiscible parts. For the Philosopher says (Ethic. ii, 5) that the passions of the soul are those emotions "which are followed by joy or sorrow." But joy and sorrow are in the concupiscible part. Therefore all the passions are in the concupiscible part, and not some in the irascible, others in the concupiscible part.

Objection 2: Further, on the words of Mt. 13:33, "The kingdom of heaven is like to leaven," etc., Jerome's gloss says: "We should have prudence in the reason; hatred of vice in the irascible faculty; desire of virtue, in the concupiscible part." But hatred is in the concupiscible faculty, as also is love, of which it is the contrary, as is stated in Topic. ii, 7. Therefore the same passion is in the concupiscible and irascible faculties.

Objection 3: Further, passions and actions differ specifically according to their objects. But the objects of the irascible and concupiscible passions are the same, viz. good and evil. Therefore the same passions are in the irascible and concupiscible faculties.

On the contrary, The acts of the different powers differ in species; for instance, to see, and to hear. But the irascible and the concupiscible are two powers into which the sensitive appetite is divided, as stated in the 1, Question 81, Article 2. Therefore, since the passions are movements of the sensitive appetite, as stated above (Question 22, Article 3), the passions of the irascible faculty are specifically distinct from those of the concupiscible part.

I answer that, The passions of the irascible part differ in species from those of the concupiscible faculty. For since different powers have different objects, as stated in the 1, Question 77, Article 3, the passions of different powers must of necessity be referred to different objects. Much more, therefore, do the passions of different faculties differ in species; since a greater difference in the object is required to diversify the species of the powers, than to diversify the species of passions or actions. For just as in the physical order, diversity of genus arises from diversity in the potentiality of matter, while diversity of species arises from diversity of form in the same matter; so in the acts of the soul, those that belong to different powers, differ not only in species but also in genus, while acts and passions regarding different specific objects, included under the one common object of a single power, differ as the species of that genus.

In order, therefore, to discern which passions are in the irascible, and which in the concupiscible, we must take the object of each of these powers. For we have stated in the 1, Question 81, Article 2, that the object of the concupiscible power is sensible good or evil, simply apprehended as such, which causes pleasure or pain. But, since the soul must, of necessity, experience difficulty or struggle at times, in acquiring some such good, or in avoiding some such evil, in so far as such good or evil is more than our animal nature can easily acquire or avoid; therefore this very good or evil, inasmuch as it is of an arduous or difficult nature, is the object of the irascible faculty. Therefore whatever passions regard good or evil absolutely, belong to the concupiscible power; for instance, joy, sorrow, love, hatred, and such like: whereas those passions which regard good or bad as arduous, through being difficult to obtain or avoid, belong to the irascible faculty; such are daring, fear, hope and the like.

Reply to Objection 1: As stated in the 1, Question 81, Article 2, the irascible faculty is bestowed on animals, in order to remove the obstacles that hinder the concupiscible power from tending towards its object, either by making some good difficult to obtain, or by making some evil hard to avoid. The result is that all the irascible passions terminate in the concupiscible passions: and thus it is that even the passions which are in the irascible faculty are followed by joy and sadness which are in the concupiscible faculty.

Reply to Objection 2: Jerome ascribes hatred of vice to the irascible faculty, not by reason of hatred, which is properly a concupiscible passion; but on account of the struggle, which belongs to the irascible power.

Reply to Objection 3: Good, inasmuch as it is delightful, moves the concupiscible power. But if it prove difficult to obtain, from this very fact it has a certain contrariety to the concupiscible power: and hence the need of another power tending to that good. The same applies to evil. And this power is the irascible faculty. Consequently the concupiscible passions are specifically different from the irascible passions.

Articulus 1

Argumentum 1

Ad primum sic proceditur. Videtur quod passiones eaedem sint in irascibili et in concupiscibili.

Dicit enim philosophus, in II ethic., quod passiones animae sunt quas sequitur gaudium et tristitia.

Sed gaudium et tristitia sunt in concupiscibili.

Ergo omnes passiones sunt in concupiscibili.

Non ergo sunt aliae in irascibili, et aliae in concupiscibili.

Argumentum 2

Praeterea, Matth. XIII, super illud, simile est regnum caelorum fermento etc., dicit Glossa Hieronymi, in ratione possideamus prudentiam, in irascibili odium vitiorum, in concupiscibili desiderium virtutum.

Sed odium est in concupiscibili, sicut et amor, cui contrariatur, ut dicitur in II topic..

Ergo eadem passio est in concupiscibili et irascibili.

Argumentum 3

Praeterea, passiones et actus differunt specie secundum obiecta.

Sed passionum irascibilis et concupiscibilis eadem obiecta sunt, scilicet bonum et malum.

Ergo eaedem sunt passiones irascibilis et concupiscibilis.

Sed Contra

Sed contra, diversarum potentiarum actus sunt specie diversi, sicut videre et audire. Sed irascibilis et concupiscibilis sunt duae potentiae dividentes appetitum sensitivum, ut in primo dictum est.

Ergo, cum passiones sint motus appetitus sensitivi, ut supra dictum est, passiones quae sunt in irascibili, erunt aliae secundum speciem a passionibus quae sunt in concupiscibili.

Corpus

Respondeo dicendum quod passiones quae sunt in irascibili et in concupiscibili, differunt specie. Cum enim diversae potentiae habeant diversa obiecta, ut in primo dictum est, necesse est quod passiones diversarum potentiarum ad diversa obiecta referantur. Unde multo magis passiones diversarum potentiarum specie differunt, maior enim differentia obiecti requiritur ad diversificandam speciem potentiarum, quam ad diversificandam speciem passionum vel actuum. Sicut enim in naturalibus diversitas generis consequitur diversitatem potentiae materiae, diversitas autem speciei diversitatem formae in eadem materia; ita in actibus animae, actus ad diversas potentias pertinentes, sunt non solum specie, sed etiam genere diversi; actus autem vel passiones respicientes diversa obiecta specialia comprehensa sub uno communi obiecto unius potentiae, differunt sicut species illius generis. Ad cognoscendum ergo quae passiones sint in irascibili, et quae in concupiscibili, oportet assumere obiectum utriusque potentiae.

Dictum est autem in primo quod obiectum potentiae concupiscibilis est bonum vel malum sensibile simpliciter acceptum, quod est delectabile vel dolorosum. Sed quia necesse est quod interdum anima difficultatem vel pugnam patiatur in adipiscendo aliquod huiusmodi bonum, vel fugiendo aliquod huiusmodi malum, inquantum hoc est quodammodo elevatum supra facilem potestatem animalis; ideo ipsum bonum vel malum, secundum quod habet rationem ardui vel difficilis, est obiectum irascibilis. Quaecumque ergo passiones respiciunt absolute bonum vel malum, pertinent ad concupiscibilem; ut gaudium, tristitia, amor, odium, et similia. Quaecumque vero passiones respiciunt bonum vel malum sub ratione ardui, prout est aliquid adipiscibile vel fugibile cum aliqua difficultate, pertinent ad irascibilem; ut audacia, timor, spes, et huiusmodi.

Ad 1

Ad primum ergo dicendum quod, sicut in primo dictum est, ad hoc vis irascibilis data est animalibus, ut tollantur impedimenta quibus concupiscibilis in suum obiectum tendere prohibetur, vel propter difficultatem boni adipiscendi, vel propter difficultatem mali superandi. Et ideo passiones irascibilis omnes terminantur ad passiones concupiscibilis. Et secundum hoc, etiam passiones quae sunt in irascibili, consequitur gaudium et tristitia, quae sunt in concupiscibili.

Ad 2

Ad secundum dicendum quod odium vitiorum attribuit Hieronymus irascibili, non propter rationem odii, quae proprie competit concupiscibili; sed propter impugnationem, quae pertinet ad irascibilem.

Ad 3

Ad tertium dicendum quod bonum inquantum est delectabile, movet concupiscibilem. Sed si bonum habeat quandam difficultatem ad adipiscendum, ex hoc ipso habet aliquid repugnans concupiscibili. Et ideo necessarium fuit esse aliam potentiam quae in id tenderet. Et eadem ratio est de malis.

Et haec potentia est irascibilis. Unde ex consequenti passiones concupiscibilis et irascibilis specie differunt.