Chapter 21

The simplicity of the human soul relative to the intellective principle

626. Here, we consider the human soul as intellective and as simple.

Simplicity is a negative property, because it excludes what is multiple, extended and material. Nevertheless, it can greatly help our knowledge of the nature of the soul, because we consider it not by itself and abstractly, but in the soul's acts and operations, which give us some positive cognition. Knowing the soul positively through feeling and consciousness, as I have said, we can obtain reflective, scientific cognition simply by seeing how the soul differs from other things, and principally from bodies. This cognition is also composed of differences, revealed in the soul's negative properties, which exclude from an ens all that it is not.

627. I maintain that none of the soul's intellective actions could be carried out except by a simple principle. Consequently, there are as many proofs of the soul's simplicity as there are intellective actions. Each proof, when carefully analysed and meditated on, is so totally convincing that our investigation would never end if we wished to identify each individually. So I will deal with the intellective soul as I dealt with the sensitive soul when I limited myself to only a few of the soul's actions, although its simplicity can be shown by an analysis of any animal action. In the present case, I will limit myself to considering the kind of simplicity of principle required to produce the first intellective actions.

628. I. The intellective soul is a subject that intuits being in general. Intuition is a simple action because its object is simple; in fact, being in general is outside space and time.(329) But a subject that intuits being in general receives its form from intuited being. Therefore the intelligent entity, whose activity totally terminates and resides in intuited being, is a principle outside space and time, totally simple and spiritual.(330) Hence, intuition clearly demonstrates the simplicity of the intuiting soul.(331)
This is the fundamental proof of the spirituality of the intellective soul. It is taken from the soul's first act, from its formal being, and includes all other proofs. Thus, if the other actions of the rational, intellective soul must be simple, the ultimate reason for their simplicity lies in the simplicity of the first act, from which second acts derive and develop.

629. II. The intuition of specific and generic essences proves the same truth. All these essences are simple, immune from space and time. Their sole difference from being in general are the few determinations with which they qualify being.

630. III. But what deserves our closest attention is the following. The simplicity of the intellective soul is confirmed even more strongly by the very thing which at first sight seems to prejudice its simplicity and indeed was used as the basis for some objections against it.

The simplicity of the sensitive principle was proved from the nature of the continuum which, I said, presupposes something simple in which the continuum exists. The sensitive principle unifies extension which is presented as something simple to the understanding. Number, however, receives its nature of number from the unity and simplicity of the intellective principle, which grasps many things simultaneously with an extremely simple act. Only a mind can unify many things into a single group, can number them and abstract from them the concepts and theory of numbers with a simple act which embraces the many in the one.

631. IV. The previous argument, which proves the simplicity of the soul from the fact that the soul can consider many things simultaneously, with the same act and in one idea, leads to another proof of the simplicity of the intelligent principle. This proof, which I have mentioned elsewhere,(332) is drawn from a syllogism and from all the acts of reasoning. Without a totally simple spirit, human beings could not make comparisons, find the differences between things, determine what is suitable and unsuitable, order means to an end, etc. All these actions presuppose a principle that embraces many things in the unity and simplicity of one and the same idea.

632. V. This leads to the argument drawn from human freedom. Human freedom requires a simple principle capable of choosing among many things. The argument, used by St. Thomas,(333) was put forward by Suarez in the following way:

633. VI. Aristotle and his followers, the Scholastics, observed most perceptively that the condition and power of a body is so limited and particularised that it admits only certain modifications and experiences which mutually exclude each other - a red body cannot simultaneously be another colour. Hence, the acts of a body do not extend beyond the little power present in the first act of the body itself. But the case is totally opposite relative to the power of the intellective soul. The intellective soul can understand, compare, etc. everything, even what is most contradictory, when presented in the required way. It cannot therefore have a corporeal nature. This proof is substantially Aristotle's proof considered in its essentials and presented in a precise form.(335)

The reason why the cognitive nature of the soul can embrace everything is that its first act, which determines its power, is informed by ens in general. Ens in general embraces virtually all entities and thus has a primal power which extends to all entia. On the other hand, body has no object distinct from itself; it terminates totally in itself, in its particular nature. The sensitive principle also has corporeal extension as its term. Its power therefore is limited to the modifications of which the extended felt element is susceptible. But the extended felt element, that is, the body, is limited in the way I have said. Hence, the sensitive principle remains limited by the very limitation of the body which constitutes the term of its first act.

634. VII. Another, very evident proof, often used by the ancients,(336) can be reduced to the previous proof. The intellective soul conceives spiritual entia, for example, itself, angels, God. It can love these and desire each as a good for itself.(337) But the extended body, as extended, cannot exercise its action outside extension or attain anything outside it. The intellective soul is therefore incorporeal.

635. VIII. Finally, the action of reflection which the soul exercises upon itself is a very clear proof of its simplicity and incorporeity, because the body performs no action upon itself.(338) Again, however, this proof is a consequence of the first. Indeed, the faculty by which thought reflects upon itself comes from the nature of being in general, object of the faculty's first act, which constitutes it as intelligent. This object is so universal that it embraces every entity, including the entity of the soul and of all its acts. In this object the soul can find itself, its acts and its objects. This is reflection. Furthermore, because being is the object of the soul's intuition and the means of reasoning, the soul can apply being as a means of reasoning to being as the object of intuition and thus reflect upon being itself. By means of being, it can reason about being.

Notes

(329) Rinnovamento, bk. 3, cc. 43-45.

(330) This basically explains why 'understanding is an act which cannot be exercised through a bodily organ, in the way that vision is exercised', as St. Thomas says (S.T., 1, q. 76, art. 1, ad 1).

(331) This excellent proof is not new. Francesco Suarez presents it clearly in these words: 'The sufficient object of the intellect IS ENS IN SO FAR AS ENS OR AS TRUE. This means that the intellect is a power of a higher order, beyond all feeling, a spiritual power, without any corporeal organ. WE KNOW FROM METAPHYSICS, and now from the argument given here, that the intellect attains all created, corporeal and spiritual entia, substance and accidents, even the uncreated God himself, and all other things which, if they are to come within the compass of a single power, must be accepted under some common concept. This concept can be only that of being, whether intelligible or real. It is therefore the concept of the sufficient object of the intellect. The first consequence is clearly seen and known in itself, namely, that the faculty embracing such a general object is outside feeling. — As I said, feeling or the cognoscitive faculty (Suarez names this incorrectly), which is organic and material (these are the same), is an extremely limited faculty because of matter' (De anima, bk. 1, c. 9, n. 3).

(332) NE, vol. 2, 670-671.

(333) C. G., 2: 65.

(334) De Anima, bk. 1, c. 9, n. 35.

(335) Aristotle's argument, although basically solid, was defective in the form in which he presented it. This perhaps explains why it has been abandoned in modern times. The principle taken by the Scholastics as the basis of the demonstration was: 'That which can know some things, must not contain any of them in its nature' (St. Thomas, S.T., 1, q. 75, art. 2). But the principle is not valid because the soul also knows the soul, even though it has the nature of soul. Another principle must be substituted: 'The acts of an ens do not extend beyond its first act, which determines its power.' But the first act of a body extends solely to having certain modifications, and nothing more at a given time. Even if these modifications were cognitions, which they are not, they would be few and determined, in contrast to the action of the soul, which is capable of knowing any ens whatsoever and many entia at the same time.

(336) Cassiodorus says: 'Although burdened by bodily mass, the soul weighs opinions with keen curiosity, considers heavenly things in depth, delicately investigates natural things, and even desires to know the most difficult properties of the Creator himself. If the soul were corporeal, it could never look at or see spiritual things with its thoughts' (De Anima, c. 4).

(337)St. Gregory Nazianzen says: 'The soul differs greatly from the body. Just as the body is fed by what is corporeal, the soul is fed by what is incorporeal' (Apologetica). Suarez, after referring to St. Gregory, adds: 'Tertullian (Liber de Anima, c. 6) tells us that this was one of the strongest arguments of the philosophers, particularly the Platonists, for proving that the soul is incorporeal. "Some philosophers," he says, "judge all bodies by what is corporeal, but the incorporeal soul by what is incorporeal, that is, by the study of wisdom." Gregory Nazianzen uses the same argument, taking it from Ammonius. Marsilio. Ficino does the same (bk. 8, De Th. Platon.), "The soul is fed by incorporeal, eternal truth", and therefore is incorporeal' (De Anima, bk. 1, c. 9, n. 18).

(338) St. Thomas uses this proof, C. G., bk. 2, c. 49.