Aquinas has discussed the appetites from a generic point of view in the previous question; now it is time to divide these appetites into those of the sentient powers (in this question) and of the intellectual powers (in the next question). In this question we’ll see that the sentient appetite is divided into two classes, one of which is to do with desire or aversion, and the other of which concerns the impulse to overcome obstacles in the fulfilment of these basic desires. In addition, we’ll begin to see that the sentient appetite is the context within which the passions (or emotions) fit; and Aquinas will make a start on his plan of how the powers of the soul work together.
The Thread of the Argument
A1: In asking whether sensuality is a purely appetitive power, Aquinas is trying partly to answer a question concerning the use of language. We’ve already seen that the sentient appetite is the appetite corresponding to sentient apprehension; the senses apprehend something and appetite inclines the animal towards or away from that something. But the word sensuality needs to be connected with this notion of being an appetitive power. This argument is completed by the etymological observation that sensuality appears to come from the Latin for a sensual movement.
A2: Aquinas, following an ancient tradition of Christian anthropology divides the faculty of sentient appetite into two powers, the irascible and the concupiscible. The basis for this division is that there is not simply an appetite towards or away from some object of perception, but also an inclination towards overcoming obstacles in the pursuit of or flight from that object. The first of these, the inclination towards those things that are agreeable or away from those that are harmful, is called the concupiscible appetite. The second, the inclination to overcome obstacles, is called the irascible appetite.
The obvious question arises as to whether one should really consider the irascible and the concupiscible appetites as two separate powers or as different aspects of the same power. The argument in favour of recognizing them as separate is twofold. In the first place, they perform separate functions in recognizing the objects of desire (or fear) and the obstacles to the possession of (or flight from) these objects; in the second case, they seem to oppose one another in some circumstances. The arousal of passions such as anger in support of the irascible appetite can lessen the desire of the concupiscible, and vice-versa.
A3: We’re gradually working our way through the components that go to make up human psychology. Of course, an interesting question that Aquinas will address at length in due time, is that of how the different powers of the soul interact to make up the acts that are particular to humans. In this article he begins such an enquiry by asking whether the irascible and concupiscible appetites are under the control of reason. It’s easy to think of arguments against such as position; after all, our experience of the passions would suggest that they have an alarming tendency to go out of all control!
Aquinas argues that the sentient appetites are under the control of reason in two ways. They’re under the control of the intellect with respect to what they do and under the control of the will with respect to how they go about doing things.
In arguing for the first of these positions, Aquinas identifies one of the ways in which the human animal is different from non-intellectual animals. In non-human animals the sentient appetite is often moved by the estimative power, the power that determines the desirability or threat offered by a perceived object. This interaction is at a level below that of the intellect or reason. When we turn to the human animal, however, we recall that the estimative power is replaced by the cogitative power; this power interacts with reason in its estimation of an object. Therefore Humans can bring to bear the powers of discursive reasoning before the sentient appetites are deployed. The second position, that the sentient appetites are under the control of the will, follows because the appetites are ordered in a hierarchy; the will being the highest of these appetites.
In his reply to the second objection, which sees the sentient appetites fighting against the will, Aquinas brings out one of his most quoted analogies. He claims that the soul rules the body like a despotic ruler, whereas the will rules the appetites as a constitutional or royal ruler. The point is that parts of the body have no alternative but to do what the soul tells them to do: a foot or hand moves when it is told to or reacts automatically in accord with the habits of the soul. The will on the other hand has to interact with sentient appetites that can, through their own powers, resist or cajole the will. There is some give and take in the control the will has over the sentient appetites but, as we see in any constitutional polity, this does not imply that the sentient powers do not obey the will.
- The reference to Gregory of Nyssa in the sed contra of the second article is in fact to a treatise called de natura hominis, written around 400AD by Nemesius of Emesa.
- In the context of the irascible appetite we see Aquinas make mention of the passions. He will have much more to say about these, especially in the so-called Treatise on the Passions in I-II.qq22-48. Briefly, there are six passions of the concupiscible appetite (joy, sadness, desire, aversion, love and hatred) and five passions in the irascible appetite (hope, despair, courage, fear and anger).
- The third article of this question raises aspects of the question of the interaction between the intellect and the sentient appetite. There is much more to say about how the powers of the soul interact and Aquinas will focus on this issue in the Treatise on The Human Act in I-II.qq6-21.
- Despite Aquinas’s arguments in the first article, in English the word sensuality seems utterly lost to theology! Now it is most associated with features of the object of perception rather than moved subject. In Latin, it first appears in Tertullian (as does so much Latin theological terminology) where it means the capacity for sensation; so it appears to have done the rounds in order to end up standing for the sensitive appetite.
- In the third article, arguing for the idea that the sentient appetites are under the control of the will, Aquinas states that “The lower appetite is not sufficient to effect movement unless the higher appetite consents”. Although he doesn’t state it, Aquinas’s analogy with constitutional rule in the reply to the second objection suggests that the consent of the higher power may often be implicit. The will doesn’t have to explicitly approve every action of the sentient appetites; rather one can see subsidiarity in the relationship.