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 FP, 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 FP, 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 FP, 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 FP, 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.

Objection 1: It would seem that the contrariety of the irascible passions is based on no other contrariety than that of good and evil. For the irascible passions are ordained to the concupiscible passions, as stated above (Article [1], ad 1). But the contrariety of the concupiscible passions is no other than that of good and evil; take, for instance, love and hatred, joy and sorrow. Therefore the same applies to the irascible passions.

Objection 2: Further, passions differ according to their objects; just as movements differ according to their termini. But there is no other contrariety of movements, except that of the termini, as is stated in Phys. v, 3. Therefore there is no other contrariety of passions, save that of the objects. Now the object of the appetite is good or evil. Therefore in no appetitive power can there be contrariety of passions other than that of good and evil.

Objection 3: Further, "every passion of the soul is by way of approach and withdrawal," as Avicenna declares in his sixth book of Physics. Now approach results from the apprehension of good; withdrawal, from the apprehension of evil: since just as "good is what all desire" (Ethic. i, 1), so evil is what all shun. Therefore, in the passions of the soul, there can be no other contrariety than that of good and evil.

On the contrary, Fear and daring are contrary to one another, as stated in Ethic. iii, 7. But fear and daring do not differ in respect of good and evil: because each regards some kind of evil. Therefore not every contrariety of the irascible passions is that of good and evil.

I answer that, Passion is a kind of movement, as stated in Phys. iii, 3. Therefore contrariety of passions is based on contrariety of movements or changes. Now there is a twofold contrariety in changes and movements, as stated in Phys. v, 5. One is according to approach and withdrawal in respect of the same term: and this contrariety belongs properly to changes, i.e. to generation, which is a change "to being," and to corruption, which is a change "from being." The other contrariety is according to opposition of termini, and belongs properly to movements: thus whitening, which is movement from black to white, is contrary to blackening, which is movement from white to black.

Accordingly there is a twofold contrariety in the passions of the soul: one, according to contrariety of objects, i.e. of good and evil; the other, according to approach and withdrawal in respect of the same term. In the concupiscible passions the former contrariety alone is to be found; viz. that which is based on the objects: whereas in the irascible passions, we find both forms of contrariety. The reason of this is that the object of the concupiscible faculty, as stated above (Article [1]), is sensible good or evil considered absolutely. Now good, as such, cannot be a term wherefrom, but only a term whereto, since nothing shuns good as such; on the contrary, all things desire it. In like manner, nothing desires evil, as such; but all things shun it: wherefore evil cannot have the aspect of a term whereto, but only of a term wherefrom. Accordingly every concupiscible passion in respect of good, tends to it, as love, desire and joy; while every concupiscible passion in respect of evil, tends from it, as hatred, avoidance or dislike, and sorrow. Wherefore, in the concupiscible passions, there can be no contrariety of approach and withdrawal in respect of the same object.

On the other hand, the object of the irascible faculty is sensible good or evil, considered not absolutely, but under the aspect of difficulty or arduousness. Now the good which is difficult or arduous, considered as good, is of such a nature as to produce in us a tendency to it, which tendency pertains to the passion of "hope"; whereas, considered as arduous or difficult, it makes us turn from it; and this pertains to the passion of "despair." In like manner the arduous evil, considered as an evil, has the aspect of something to be shunned; and this belongs to the passion of "fear": but it also contains a reason for tending to it, as attempting something arduous, whereby to escape being subject to evil; and this tendency is called "daring." Consequently, in the irascible passions we find contrariety in respect of good and evil (as between hope and fear): and also contrariety according to approach and withdrawal in respect of the same term (as between daring and fear).

From what has been said the replies to the objections are evident.

Objection 1: It would seem that every passion of the soul has a contrary. For every passion of the soul is either in the irascible or in the concupiscible faculty, as stated above (Article [1]). But both kinds of passion have their respective modes of contrariety. Therefore every passion of the soul has its contrary.

Objection 2: Further, every passion of the soul has either good or evil for its object; for these are the common objects of the appetitive part. But a passion having good for its object, is contrary to a passion having evil for its object. Therefore every passion has a contrary.

Objection 3: Further, every passion of the soul is in respect of approach or withdrawal, as stated above (Article [2]). But every approach has a corresponding contrary withdrawal, and vice versa. Therefore every passion of the soul has a contrary.

On the contrary, Anger is a passion of the soul. But no passion is set down as being contrary to anger, as stated in Ethic. iv, 5. Therefore not every passion has a contrary.

I answer that, The passion of anger is peculiar in this, that it cannot have a contrary, either according to approach and withdrawal, or according to the contrariety of good and evil. For anger is caused by a difficult evil already present: and when such an evil is present, the appetite must needs either succumb, so that it does not go beyond the limits of "sadness," which is a concupiscible passion; or else it has a movement of attack on the hurtful evil, which movement is that of "anger." But it cannot have a movement of withdrawal: because the evil is supposed to be already present or past. Thus no passion is contrary to anger according to contrariety of approach and withdrawal.

In like manner neither can there be according to contrariety of good and evil. Because the opposite of present evil is good obtained, which can be no longer have the aspect of arduousness or difficulty. Nor, when once good is obtained, does there remain any other movement, except the appetite's repose in the good obtained; which repose belongs to joy, which is a passion of the concupiscible faculty.

Accordingly no movement of the soul can be contrary to the movement of anger, and nothing else than cessation from its movement is contrary thereto; thus the Philosopher says (Rhet. ii, 3) that "calm is contrary to anger," by opposition not of contrariety but of negation or privation.

From what has been said the replies to the objections are evident.

Objection 1: It would seem that there cannot be, in the same power, specifically different passions that are not contrary to one another. For the passions of the soul differ according to their objects. Now the objects of the soul's passions are good and evil; and on this distinction is based the contrariety of the passions. Therefore no passions of the same power, that are not contrary to one another, differ specifically.

Objection 2: Further, difference of species implies a difference of form. But every difference of form is in respect of some contrariety, as stated in Metaph. x, 8. Therefore passions of the same power, that are not contrary to one another, do not differ specifically.

Objection 3: Further, since every passion of the soul consists in approach or withdrawal in respect of good or evil, it seems that every difference in the passions of the soul must needs arise from the difference of good and evil; or from the difference of approach and withdrawal; or from degrees in approach or withdrawal. Now the first two differences cause contrariety in the passions of the soul, as stated above (Article [2]): whereas the third difference does not diversify the species; else the species of the soul's passions would be infinite. Therefore it is not possible for passions of the same power to differ in species, without being contrary to one another.

On the contrary, Love and joy differ in species, and are in the concupiscible power; and yet they are not contrary to one another; rather, in fact, one causes the other. Therefore in the same power there are passions that differ in species without being contrary to one another.

I answer that, Passions differ in accordance with their active causes, which, in the case of the passions of the soul, are their objects. Now, the difference in active causes may be considered in two ways: first, from the point of view of their species or nature, as fire differs from water; secondly, from the point of view of the difference in their active power. In the passions of the soul we can treat the difference of their active or motive causes in respect of their motive power, as if they were natural agents. For every mover, in a fashion, either draws the patient to itself, or repels it from itself. Now in drawing it to itself, it does three things in the patient. Because, in the first place, it gives the patient an inclination or aptitude to tend to the mover: thus a light body, which is above, bestows lightness on the body generated, so that it has an inclination or aptitude to be above. Secondly, if the generated body be outside its proper place, the mover gives it movement towards that place. Thirdly, it makes it to rest, when it shall have come to its proper place: since to the same cause are due, both rest in a place, and the movement to that place. The same applies to the cause of repulsion.

Now, in the movements of the appetitive faculty, good has, as it were, a force of attraction, while evil has a force of repulsion. In the first place, therefore, good causes, in the appetitive power, a certain inclination, aptitude or connaturalness in respect of good: and this belongs to the passion of "love": the corresponding contrary of which is "hatred" in respect of evil. Secondly, if the good be not yet possessed, it causes in the appetite a movement towards the attainment of the good beloved: and this belongs to the passion of "desire" or "concupiscence": and contrary to it, in respect of evil, is the passion of "aversion" or "dislike." Thirdly, when the good is obtained, it causes the appetite to rest, as it were, in the good obtained: and this belongs to the passion of "delight" or "joy"; the contrary of which, in respect of evil, is "sorrow" or "sadness."

On the other hand, in the irascible passions, the aptitude, or inclination to seek good, or to shun evil, is presupposed as arising from the concupiscible faculty, which regards good or evil absolutely. And in respect of good not yet obtained, we have "hope" and "despair." In respect of evil not yet present we have "fear" and "daring." But in respect of good obtained there is no irascible passion: because it is no longer considered in the light of something arduous, as stated above (Article [3]). But evil already present gives rise to the passion of "anger."

Accordingly it is clear that in the concupiscible faculty there are three couples of passions; viz. love and hatred, desire and aversion, joy and sadness. In like manner there are three groups in the irascible faculty; viz. hope and despair, fear and daring, and anger which has not contrary passion.

Consequently there are altogether eleven passions differing specifically; six in the concupiscible faculty, and five in the irascible; and under these all the passions of the soul are contained.

From this the replies to the objections are evident.