Whether the soul is man?
Objection 1: It would seem that the soul is man. For it is written, “Though our outward man is corrupted, yet the inward man is renewed day by day.” (2 Cor. iv. 16) But that which is within man is the soul. Therefore the soul is the inward man.
It would seem that soul is to be identified with man. It seems to be man’s inner self and the inner self is the true self. The true man is therefore his interior and inward self or being. Therefore, the soul is the whole of man.
Objection 2: Further, the human soul is a substance. But it is not a universal substance. Therefore it is a particular substance. Therefore it is a “hypostasis” or a person; and it can only be a human person. Therefore the soul is man; for a human person is a man.
The human soul is not a universal substance or a universal nature as the Islamic Commentators on Aristotle wrongly assert. The human soul is a particular substance that identifies one man as man in distinction from another. For while one man is distinguished from another the distinction is found in the difference that marks him off as an individual. But an individual man is an individual soul. An individual soul is a human person. Therefore, the soul is the whole man.
On the contrary, Augustine (De Civ. Dei xix, 3) commends Varro as holding “that man is not a mere soul, nor a mere body; but both soul and body.”
Against the Platonists, St. Augustine reminds us that man is not merely or only a soul but is the composite of soul and body. His flesh is neither accidental nor evil. His body and soul together must form the composite whole that make up his substance as a rational animal. What is good is the whole man, with all of his parts. His soul and body are necessary parts whose actualization contribute to his substantial being.
I answer that, The assertion “the soul is man,” can be taken in two senses. First, that man is a soul; though this particular man, Socrates, for instance, is not a soul, but composed of soul and body. I say this, forasmuch as some held that the form alone belongs to the species; while matter is part of the individual, and not the species. This cannot be true; for to the nature of the species belongs what the definition signifies; and in natural things the definition does not signify the form only, but the form and the matter. Hence in natural things the matter is part of the species; not, indeed, signate matter, which is the principle of individuality; but the common matter. For as it belongs to the notion of this particular man to be composed of this soul, of this flesh, and of these bones; so it belongs to the notion of man to be composed of soul, flesh, and bones; for whatever belongs in common to the substance of all the individuals contained under a given species, must belong to the substance of the species.
Man is a natural creature. By definition he is a composite of soul and body. To say this is to locate man’s being as what is natural to time and space and its limitations. Man is not a pure spirit like angels. He is a substance whose nature is the unity of form and matter. The species “man” as a rational animal is not merely a form with the accidental attributes of matter. Man is not man unless he is the unity of form and matter as a substance that is both intellectual, sensitive, and vegetative. So the substance of the species includes form and matter as soul and body.
It may also be understood in this sense, that this soul is this man; and this could be held if it were supposed that the operation of the sensitive soul were proper to it, apart from the body; because in that case all the operations which are attributed to man would belong to the soul only; and whatever performs the operations proper to a thing, is that thing; wherefore that which performs the operations of a man is man. But it has been shown that sensation is not the operation of the soul only. Since, then, sensation is an operation of man, but not proper to him, it is clear that man is not a soul only, but something composed of soul and body. Plato, through supposing that sensation was proper to the soul, could maintain man to be a soul making use of the body.
Man is not sensitive soul apart from the body. Sensitive soul is the capacity that acts as mediator between the nutritive or vegetative soul and the intellectual or rational soul. If man were merely a sensitive soul, then soul might be identified with man. But the sensitive soul is one of the kinds of soul that works with the others and then only and always in the body. In the Platonic view the soul is man and makes use of a body as a kind of extension to its nature. ‘Aristotle defines the soul as the act of a natural body with the capacity for life; and as the first act of a natural organic body. Soul is thus the formal cause of the animal, the efficient cause of its motions, as well as its final cause. The body cannot be the principle that accounts for life, since a body, when deprived of life, is still a body, but not alive. The body is matter to the soul, and soul is form or act to the potentiality of the body. Moreover, the matter, i.e. the constituents that make up the body, are constantly changing while the animal persists. The animal’s form or functional organization, i.e. organization of material parts by which an animal accomplishes its vital functions, remains the same. This form is the animal’s soul.’ (‘Thomistic Psychology’: Thomistic Philosophy Page)
Again, man is not a sensitive soul only. He is also a vegetative and an intellective soul. But he is also body. So the soul is the form of the body. The form of the rational animal known as ‘man’ moves man intellectively, sensitively, and vegetatively. ‘There is the vegetative soul which accounts for the functions of nutrition and reproduction. Plants have only this kind of soul. Next, there is the sensitive soul, by which higher animals perceive and respond to their environment. This kind of soul, for some animals, also includes the power of local motion. Finally, there is the rational soul, by which humans are able to use speech and have abstract thoughts. In all of the higher kinds of organisms, the functions that were performed by lower kinds of souls are performed by the higher.’ (Idem)
Reply to Objection 1: According to the Philosopher (Ethic. ix, 8), a thing seems to be chiefly what is principle in it; thus what the governor of a state does, the state is said to do. In this way sometimes what is principle in man is said to be man; sometimes, indeed, the intellectual part which, in accordance with truth, is called the “inward” man; and sometimes the sensitive part with the body is called man in the opinion of those whose observation does not go beyond the senses. And this is called the “outward” man.
A thing is what is principle in it. What the ruling principle does defines and articulates the substance or essence. So what is principle in man should be the nature of man. So we can see why the intellectual and spiritual principle of man is often identified with the man. If the intellectual soul is responsible for man’s redemption we can see that the sensitive principle is often said to be a false or alter-principle that comes with man’s Fall from Grace. But the soul is rather to be understood here as the form of the body that actualizes its potential in the service of God. Another way of putting it is that the soul is the actualizing principle that makes the whole man, as rational animal, complete. Thus, the “inward man” is not just the intellectual soul but the whole man who is embracing redemptive truth in all of his parts.
Reply to Objection 2: Not every particular substance is a hypostasis or a person, but that which has the complete nature of its species. Hence a hand, or a foot, is not called a hypostasis, or a person; nor, likewise, is the soul alone so called, since it is a part of the human species.
Only the complete nature or essence of a species can qualify an individual to be a particular substance. The soul alone is not a person because it is only part of the composite human species. Soul and body must blend together in unity to constitute a substantial human being. So to be truly human the soul and body work together in the service of God. Amen.