seventh day, since, as we explained (Q. 72, ad 4), the blessing referred to the increase by multiplication; for which reason God said to the creatures which He blessed: "Increase and multiply." Now, this increase is effected through God's Providence over His creatures, securing the generation of like from like. And according to the second meaning, it is right that the seventh day should have been sanctified, since the special sanctification of every creature consists in resting in God. For this reason things dedicated to God are said to be sanctified.
Reply Obj. 1: The seventh day is said to be sanctified not because anything can accrue to God, or be taken from Him, but because something is added to creatures by their multiplying, and by their resting in God.
Reply Obj. 2: In the first six days creatures were produced in their first causes, but after being thus produced, they are multiplied and preserved, and this work also belongs to the Divine goodness. And the perfection of this goodness is made most clear by the knowledge that in it alone God finds His own rest, and we may find ours in its fruition.
Reply Obj. 3: The good mentioned in the works of each day belongs to the first institution of nature; but the blessing attached to the seventh day, to its propagation.
QUESTION 74 ON ALL THE SEVEN DAYS IN COMMON (In Three Articles) We next consider all the seven days in common: and there are three points of inquiry: (1) As to the sufficiency of these days; (2) Whether they are all one day, or more than one?
(3) As to certain modes of speaking which Scripture uses in narrating the works of the six days.
Whether these days are sufficiently enumerated?
Objection 1: It would seem that these days are not sufficiently enumerated. For the work of creation is no less distinct from the works of distinction and adornment than these two works are from one another. But separate days are assigned to distinction and to adornment, and therefore separate days should be assigned to creation.
Obj. 2: Further, air and fire are nobler elements than earth and water. But one day is assigned to the distinction of water, and another to the distinction of the land. Therefore, other days ought to be devoted to the distinction of fire and air.
Obj. 3: Further, fish differ from birds as much as birds differ from the beasts of the earth, whereas man differs more from other animals than all animals whatsoever differ from each other. But one day is devoted to the production of fishes, and another to that of the beast of the earth. Another day, then, ought to be assigned to the production of birds and another to that of man.
Obj. 4: Further, it would seem, on the other hand, that some of these days are superfluous. Light, for instance, stands to the luminaries in the relation of accident to subject. But the subject is produced at the same time as the accident proper to it. The light and the luminaries, therefore, ought not to have been produced on different days.
Obj. 5: Further, these days are devoted to the first instituting of the world. But as on the seventh day nothing was instituted, that day ought not to be enumerated with the others.
_I answer that,_ The reason of the distinction of these days is made clear by what has been said above (Q. 70, A. 1), namely, that the parts of the world had first to be distinguished, and then each part adorned and filled, as it were, by the beings that inhabit it. Now the parts into which the corporeal creation is divided are three, according to some holy writers, these parts being the heaven, or highest part, the water, or middle part, and the earth, or the lowest part. Thus the Pythagoreans teach that perfection consists in three things, the beginning, the middle, and the end. The first part, then, is distinguished on the first day, and adorned on the fourth, the middle part distinguished on the middle day, and adorned on the fifth, and the third part distinguished on the third day, and adorned on the sixth. But Augustine, while agreeing with the above writers as to the last three days, differs as to the first three, for, according to him, spiritual creatures are formed on the first day, and corporeal on the two others, the higher bodies being formed on the first these two days, and the lower on the second. Thus, then, the perfection of the Divine works corresponds to the perfection of the number six, which is the sum of its aliquot parts, one, two, three; since one day is assigned to the forming of spiritual creatures, two to that of corporeal creatures, and three to the work of adornment.
Reply Obj. 1: According to Augustine, the work of creation belongs to the production of formless matter, and of the formless spiritual nature, both of which are outside of time, as he himself says (Confess. xii, 12). Thus, then, the creation of either is set down before there was any day. But it may also be said, following other holy writers, that the works of distinction and adornment imply certain changes in the creature which are measurable by time; whereas the work of creation lies only in the Divine act producing the substance of beings instantaneously. For this reason, therefore, every work of distinction and adornment is said to take place "in a day," but creation "in the beginning" which denotes something indivisible.
Reply Obj. 2: Fire and air, as not distinctly known by the unlettered, are not expressly named by Moses among the parts of the world, but reckoned with the intermediate part, or water, especially as regards the lowest part of the air; or with the heaven, to which the higher region of air approaches, as Augustine says (Gen. ad lit.
ii, 13).
Reply Obj. 3: The production of animals is recorded with reference to their adorning the various parts of the world, and therefore the days of their production are separated or united according as the animals adorn the same parts of the world, or different parts.
Reply Obj. 4: The nature of light, as existing in a subject, was made on the first day; and the making of the luminaries on the fourth day does not mean that their substance was produced anew, but that they then received a form that they had not before, as said above (Q. 70, [A. 1] ad 2).
Reply Obj. 5: According to Augustine (Gen. ad lit. iv, 15), after all that has been recorded that is assigned to the six days, something distinct is attributed to the seventh--namely, that on it God rested in Himself from His works: and for this reason it was right that the seventh day should be mentioned after the six. It may also be said, with the other writers, that the world entered on the seventh day upon a new state, in that nothing new was to be added to it, and that therefore the seventh day is mentioned after the six, from its being devoted to cessation from work.
Whether All These Days Are One Day?
Objection 1: It would seem that all these days are one day. For it is written (Gen. 2:4, 5): "These are the generations of the heaven and the earth, when they were created, in the day that the Lord...made the heaven and the earth, and every plant of the field, before it sprung up in the earth." Therefore the day in which God made "the heaven and the earth, and every plant of the field," is one and the same day. But He made the heaven and the earth on the first day, or rather before there was any day, but the plant of the field He made on the third day. Therefore the first and third days are but one day, and for a like reason all the rest.
Obj. 2: Further, it is said (Ecclus. 18:1): "He that liveth for ever, created all things together." But this would not be the case if the days of these works were more than one. Therefore they are not many but one only.
Obj. 3: Further, on the seventh day God ceased from all new works.
If, then, the seventh day is distinct from the other days, it follows that He did not make that day; which is not admissible.
Obj. 4: Further, the entire work ascribed to one day God perfected in an instant, for with each work are the words (God) "said...and it was...done." If, then, He had kept back His next work to another day, it would follow that for the remainder of a day He would have ceased from working and left it vacant, which would be superfluous. The day, therefore, of the preceding work is one with the day of the work that follows.
_On the contrary,_ It is written (Gen. 1), "The evening and the morning were the second day...the third day," and so on. But where there is a second and third there are more than one. There was not, therefore, only one day.
_I answer that,_ On this question Augustine differs from other expositors. His opinion is that all the days that are called seven, are one day represented in a sevenfold aspect (Gen. ad lit. iv, 22; De Civ. Dei xi, 9; Ad Orosium xxvi); while others consider there were seven distinct days, not one only. Now, these two opinions, taken as explaining the literal text of Genesis, are certainly widely different. For Augustine understands by the word "day," the knowledge in the mind of the angels, and hence, according to him, the first day denotes their knowledge of the first of the Divine works, the second day their knowledge of the second work, and similarly with the rest.
Thus, then, each work is said to have been wrought in some one of these days, inasmuch as God wrought nothing in the universe without impressing the knowledge thereof on the angelic mind; which can know many things at the same time, especially in the Word, in Whom all angelic knowledge is perfected and terminated. So the distinction of days denotes the natural order of the things known, and not a succession in the knowledge acquired, or in the things produced.
Moreover, angelic knowledge is appropriately called "day," since light, the cause of day, is to be found in spiritual things, as Augustine observes (Gen. ad lit. iv, 28). In the opinion of the others, however, the days signify a succession both in time, and in the things produced.
If, however, these two explanations are looked at as referring to the mode of production, they will be found not greatly to differ, if the diversity of opinion existing on two points, as already shown (Q. 67, A. 1; Q. 69, A. 1), between Augustine and other writers is taken into account. First, because Augustine takes the earth and the water as first created, to signify matter totally without form; but the making of the firmament, the gathering of the waters, and the appearing of dry land, to denote the impression of forms upon corporeal matter.
But other holy writers take the earth and the water, as first created, to signify the elements of the universe themselves existing under the proper forms, and the works that follow to mean some sort of distinction in bodies previously existing, as also has been shown plants and animals were produced actually in the work of the six days; Augustine, that they were produced potentially. Now the opinion of Augustine, that the works of the six days were simultaneous, is consistent with either view of the mode of production. For the other writers agree with him that in the first production of things matter existed under the substantial form of the elements, and agree with him also that in the first instituting of the world animals and plants did not exist actually. There remains, however, a difference as to four points; since, according to the latter, there was a time, after the production of creatures, in which light did not exist, the firmament had not been formed, and the earth was still covered by the waters, nor had the heavenly bodies been formed, which is the fourth difference; which are not consistent with Augustine's explanation. In order, therefore, to be impartial, we must meet the arguments of either side.
Reply Obj. 1: On the day on which God created the heaven and the earth, He created also every plant of the field, not, indeed, actually, but "before it sprung up in the earth," that is, potentially. And this work Augustine ascribes to the third day, but other writers to the first instituting of the world.
Reply Obj. 2: God created all things together so far as regards their substance in some measure formless. But He did not create all things together, so far as regards that formation of things which lies in distinction and adornment. Hence the word "creation" is significant.
Reply Obj. 3: On the seventh day God ceased from making new things, but not from providing for their increase, and to this latter work it belongs that the first day is succeeded by other days.
Reply Obj. 4: All things were not distinguished and adorned together, not from a want of power on God's part, as requiring time in which to work, but that due order might be observed in the instituting of the world. Hence it was fitting that different days should be assigned to the different states of the world, as each succeeding work added to the world a fresh state of perfection.
Reply Obj. 5: According to Augustine, the order of days refers to the natural order of the works attributed to the days.
Whether Scripture Uses Suitable Words to Express the Work of the Six Days?
Objection 1: It would seem the Scripture does not use suitable words to express the works of the six days. For as light, the firmament, and other similar works were made by the Word of God, so were the heaven and the earth. For "all things were made by Him" (John 1:3).
Therefore in the creation of heaven and earth, as in the other works, mention should have been made of the Word of God.
Obj. 2: Further, the water was created by God, yet its creation is not mentioned. Therefore the creation of the world is not sufficiently described.
Obj. 3: Further, it is said (Gen. 1:31): "God saw all the things that He had made, and they were very good." It ought, then, to have been said of each work, "God saw that it was good." The omission, therefore, of these words in the work of creation and in that of the second day, is not fitting.
Obj. 4: Further, the Spirit of God is God Himself. But it does not befit God to move and to occupy place. Therefore the words, "The Spirit of God moved over the waters," are unbecoming.
Obj. 5: Further, what is already made is not made over again.
Therefore to the words, "God said: Let the firmament be made...and it was so," it is superfluous to add, "God made the firmament."
And the like is to be said of other works.
Obj. 6: Further, evening and morning do not sufficiently divide the day, since the day has many parts. Therefore the words, "The evening and morning were the second day" or, "the third day," are not suitable.
Obj. 7: Further, "first," not "one," corresponds to "second" and "third." It should therefore have been said that, "The evening and the morning were the first day," rather than "one day."
Reply Obj. 1: According to Augustine (Gen. ad lit. i, 4), the person of the Son is mentioned both in the first creation of the world, and in its distinction and adornment, but differently in either place.
For distinction and adornment belong to the work by which the world receives its form. But as the giving form to a work of art is by means of the form of the art in the mind of the artist, which may be called his intelligible word, so the giving form to every creature is by the word of God; and for this reason in the works of distinction and adornment the Word is mentioned. But in creation the Son is mentioned as the beginning, by the words, "In the beginning God created," since by creation is understood the production of formless matter. But according to those who hold that the elements were created from the first under their proper forms, another explanation must be given; and therefore Basil says (Hom. ii, iii in Hexaem.)
that the words, "God said," signify a Divine command. Such a command, however, could not have been given before creatures had been produced that could obey it.
Reply Obj. 2: According to Augustine (De Civ. Dei ix, 33), by the heaven is understood the formless spiritual nature, and by the earth, the formless matter of all corporeal things, and thus no creature is omitted. But, according to Basil (Hom. i in Hexaem.), the heaven and the earth, as the two extremes, are alone mentioned, the intervening things being left to be understood, since all these move heavenwards, if light, or earthwards, if heavy. And others say that under the word, "earth," Scripture is accustomed to include all the four elements as (Ps. 148:7,8) after the words, "Praise the Lord from the earth," is added, "fire, hail, snow, and ice."
Reply Obj. 3: In the account of the creation there is found something to correspond to the words, "God saw that it was good," used in the work of distinction and adornment, and this appears from the consideration that the Holy Spirit is Love. Now, "there are two things," says Augustine (Gen. ad lit. i, 8) which came from God's love of His creatures, their existence and their permanence. That they might then exist, and exist permanently, "the Spirit of God," it is said, "moved over the waters"--that is to say, over that formless matter, signified by water, even as the love of the artist moves over the materials of his art, that out of them he may form his work. And the words, "God saw that it was good," signify that the things that He had made were to endure, since they express a certain satisfaction taken by God in His works, as of an artist in his art: not as though He knew the creature otherwise, or that the creature was pleasing to Him otherwise, than before He made it. Thus in either work, of creation and of formation, the Trinity of Persons is implied. In creation the Person of the Father is indicated by God the Creator, the Person of the Son by the beginning, in which He created, and the Person of the Holy Ghost by the Spirit that moved over the waters.
But in the formation, the Person of the Father is indicated by God that speaks, and the Person of the Son by the Word in which He speaks, and the Person of the Holy Spirit by the satisfaction with which God saw that what was made was good. And if the words, "God saw that it was good," are not said of the work of the second day, this is because the work of distinguishing the waters was only begun on that day, but perfected on the third. Hence these words, that are said of the third day, refer also to the second. Or it may be that Scripture does not use these words of approval of the second day's work, because this is concerned with the distinction of things not evident to the senses of mankind. Or, again, because by the firmament is simply understood the cloudy region of the air, which is not one of the permanent parts of the universe, nor of the principal divisions of the world. The above three reasons are given by Rabbi Moses [*Perplex. ii.], and to these may be added a mystical one derived from numbers and assigned by some writers, according to whom the work of the second day is not marked with approval because the second number is an imperfect number, as receding from the perfection of unity.
Reply Obj. 4: Rabbi Moses (Perplex. ii) understands by the "Spirit of the Lord," the air or the wind, as Plato also did, and says that it is so called according to the custom of Scripture, in which these things are throughout attributed to God. But according to the holy writers, the Spirit of the Lord signifies the Holy Ghost, Who is said to "move over the water"--that is to say, over what Augustine holds to mean formless matter, lest it should be supposed that God loved of necessity the works He was to produce, as though He stood in need of them. For love of that kind is subject to, not superior to, the object of love. Moreover, it is fittingly implied that the Spirit moved over that which was incomplete and unfinished, since that movement is not one of place, but of pre-eminent power, as Augustine says (Gen. ad lit. i, 7). It is the opinion, however, of Basil (Hom.
ii in Hexaem.) that the Spirit moved over the element of water, "fostering and quickening its nature and impressing vital power, as the hen broods over her chickens." For water has especially a life-giving power, since many animals are generated in water, and the seed of all animals is liquid. Also the life of the soul is given by the water of baptism, according to John 3:5: "Unless a man be born again of water and the Holy Ghost, he cannot enter into the kingdom of God."
Reply Obj. 5: According to Augustine (Gen. ad lit. i, 8), these three phrases denote the threefold being of creatures; first, their being in the Word, denoted by the command "Let...be made"; secondly, their being in the angelic mind, signified by the words, "It was...done"; thirdly, their being in their proper nature, by the words, "He made." And because the formation of the angels is recorded on the first day, it was not necessary there to add, "He made." It may also be said, following other writers, that the words, "He said," and "Let...be made," denote God's command, and the words, "It was done," the fulfilment of that command. But as it was necessary, for the sake of those especially who have asserted that all visible things were made by the angels, to mention how things were made, it is added, in order to remove that error, that God Himself made them. Hence, in each work, after the words, "It was done," some act of God is expressed by some such words as, "He made," or, "He divided," or, "He called."
Reply Obj. 6: According to Augustine (Gen. ad lit. iv, 22, 30), by the "evening" and the "morning" are understood the evening and the morning knowledge of the angels, which has been explained (Q. 58, A. 6, 7). But, according to Basil (Hom. ii in Hexaem.), the entire period takes its name, as is customary, from its more important part, the day. An instance of this is found in the words of Jacob, "The days of my pilgrimage," where night is not mentioned at all. But the evening and the morning are mentioned as being the ends of the day, since day begins with morning and ends with evening, or because evening denotes the beginning of night, and morning the beginning of day. It seems fitting, also, that where the first distinction of creatures is described, divisions of time should be denoted only by what marks their beginning. And the reason for mentioning the evening first is that as the evening ends the day, which begins with the light, the termination of the light at evening precedes the termination of the darkness, which ends with the morning. But Chrysostom's explanation is that thereby it is intended to show that the natural day does not end with the evening, but with the morning (Hom. v in Gen.).
Reply Obj. 7: The words "one day" are used when day is first instituted, to denote that one day is made up of twenty-four hours.
Hence, by mentioning "one," the measure of a natural day is fixed.
Another reason may be to signify that a day is completed by the return of the sun to the point from which it commenced its course.
And yet another, because at the completion of a week of seven days, the first day returns which is one with the eighth day. The three reasons assigned above are those given by Basil (Hom. ii in Hexaem.).
TREATISE ON MAN (QQ. 75-102) QUESTION 75 OF MAN WHO IS COMPOSED OF A SPIRITUAL AND A CORPOREAL SUBSTANCE: AND IN THE FIRST PLACE, CONCERNING WHAT BELONGS TO THE ESSENCE OF THE SOUL (In Seven Articles) Having treated of the spiritual and of the corporeal creature, we now proceed to treat of man, who is composed of a spiritual and corporeal substance. We shall treat first of the nature of man, and secondly of his origin. Now the theologian considers the nature of man in relation to the soul; but not in relation to the body, except in so far as the body has relation to the soul. Hence the first object of our consideration will be the soul. And since Dionysius (Ang. Hier. xi) says that three things are to be found in spiritual substances--essence, power, and operation--we shall treat first of what belongs to the essence of the soul; secondly, of what belongs to its power; thirdly, of what belongs to its operation.
Concerning the first, two points have to be considered; the first is the nature of the soul considered in itself; the second is the union of the soul with the body. Under the first head there are seven points of inquiry.
(1) Whether the soul is a body?
(2) Whether the human soul is a subsistence?
(3) Whether the souls of brute animals are subsistent?
(4) Whether the soul is man, or is man composed of soul and body?
(5) Whether the soul is composed of matter and form?
(6) Whether the soul is incorruptible?
(7) Whether the soul is of the same species as an angel?
Whether the Soul Is a Body?
Objection 1: It would seem that the soul is a body. For the soul is the moving principle of the body. Nor does it move unless moved.
First, because seemingly nothing can move unless it is itself moved, since nothing gives what it has not; for instance, what is not hot does not give heat. Secondly, because if there be anything that moves and is not moved, it must be the cause of eternal, unchanging movement, as we find proved Phys. viii, 6; and this does not appear to be the case in the movement of an animal, which is caused by the soul.
Therefore the soul is a mover moved. But every mover moved is a body.
Therefore the soul is a body.
Obj. 2: Further, all knowledge is caused by means of a likeness.
But there can be no likeness of a body to an incorporeal thing. If, therefore, the soul were not a body, it could not have knowledge of corporeal things.
Obj. 3: Further, between the mover and the moved there must be contact. But contact is only between bodies. Since, therefore, the soul moves the body, it seems that the soul must be a body.
_On the contrary,_ Augustine says (De Trin. vi, 6) that the soul "is simple in comparison with the body, inasmuch as it does not occupy space by its bulk."
_I answer that,_ To seek the nature of the soul, we must premise that the soul is defined as the first principle of life of those things which live: for we call living things "animate," [*i.e. having a soul] and those things which have no life, "inanimate." Now life is shown principally by two actions, knowledge and movement. The philosophers of old, not being able to rise above their imagination, supposed that the principle of these actions was something corporeal: for they asserted that only bodies were real things; and that what is not corporeal is nothing: hence they maintained that the soul is something corporeal. This opinion can be proved to be false in many ways; but we shall make use of only one proof, based on universal and certain principles, which shows clearly that the soul is not a body.
It is manifest that not every principle of vital action is a soul, for then the eye would be a soul, as it is a principle of vision; and the same might be applied to the other instruments of the soul: but it is the _first_ principle of life, which we call the soul. Now, though a body may be a principle of life, as the heart is a principle of life in an animal, yet nothing corporeal can be the first principle of life. For it is clear that to be a principle of life, or to be a living thing, does not belong to a body as such; since, if that were the case, every body would be a living thing, or a principle of life. Therefore a body is competent to be a living thing or even a principle of life, as "such" a body. Now that it is actually such a body, it owes to some principle which is called its act. Therefore the soul, which is the first principle of life, is not a body, but the act of a body; thus heat, which is the principle of calefaction, is not a body, but an act of a body.
Reply Obj. 1: As everything which is in motion must be moved by something else, a process which cannot be prolonged indefinitely, we must allow that not every mover is moved. For, since to be moved is to pass from potentiality to actuality, the mover gives what it has to the thing moved, inasmuch as it causes it to be in act. But, as is shown in _Phys._ viii, 6, there is a mover which is altogether immovable, and not moved either essentially, or accidentally; and such a mover can cause an invariable movement. There is, however, another kind of mover, which, though not moved essentially, is moved accidentally; and for this reason it does not cause an invariable movement; such a mover, is the soul. There is, again, another mover, which is moved essentially--namely, the body. And because the philosophers of old believed that nothing existed but bodies, they maintained that every mover is moved; and that the soul is moved directly, and is a body.
Reply Obj. 2: The likeness of a thing known is not of necessity actually in the nature of the knower; but given a thing which knows potentially, and afterwards knows actually, the likeness of the thing known must be in the nature of the knower, not actually, but only potentially; thus color is not actually in the pupil of the eye, but only potentially. Hence it is necessary, not that the likeness of corporeal things should be actually in the nature of the soul, but that there be a potentiality in the soul for such a likeness. But the ancient philosophers omitted to distinguish between actuality and potentiality; and so they held that the soul must be a body in order to have knowledge of a body; and that it must be composed of the principles of which all bodies are formed in order to know all bodies.
Reply Obj. 3: There are two kinds of contact; of "quantity," and of "power." By the former a body can be touched only by a body; by the latter a body can be touched by an incorporeal thing, which moves that body.
Whether the Human Soul Is Something Subsistent?
Objection 1: It would seem that the human soul is not something subsistent. For that which subsists is said to be "this particular thing." Now "this particular thing" is said not of the soul, but of that which is composed of soul and body. Therefore the soul is not something subsistent.
Obj. 2: Further, everything subsistent operates. But the soul does not operate; for, as the Philosopher says (De Anima i, 4), "to say that the soul feels or understands is like saying that the soul weaves or builds." Therefore the soul is not subsistent.
Obj. 3: Further, if the soul were subsistent, it would have some operation apart from the body. But it has no operation apart from the body, not even that of understanding: for the act of understanding does not take place without a phantasm, which cannot exist apart from the body. Therefore the human soul is not something subsistent.
_On the contrary,_ Augustine says (De Trin. x, 7): "Who understands that the nature of the soul is that of a substance and not that of a body, will see that those who maintain the corporeal nature of the soul, are led astray through associating with the soul those things without which they are unable to think of any nature--i.e. imaginary pictures of corporeal things." Therefore the nature of the human intellect is not only incorporeal, but it is also a substance, that is, something subsistent.
_I answer that,_ It must necessarily be allowed that the principle of intellectual operation which we call the soul, is a principle both incorporeal and subsistent. For it is clear that by means of the intellect man can have knowledge of all corporeal things. Now whatever knows certain things cannot have any of them in its own nature; because that which is in it naturally would impede the knowledge of anything else. Thus we observe that a sick man's tongue being vitiated by a feverish and bitter humor, is insensible to anything sweet, and everything seems bitter to it. Therefore, if the intellectual principle contained the nature of a body it would be unable to know all bodies. Now every body has its own determinate nature. Therefore it is impossible for the intellectual principle to be a body. It is likewise impossible for it to understand by means of a bodily organ; since the determinate nature of that organ would impede knowledge of all bodies; as when a certain determinate color is not only in the pupil of the eye, but also in a glass vase, the liquid in the vase seems to be of that same color.
Therefore the intellectual principle which we call the mind or the intellect has an operation _per se_ apart from the body. Now only that which subsists can have an operation _per se._ For nothing can operate but what is actual: for which reason we do not say that heat imparts heat, but that what is hot gives heat. We must conclude, therefore, that the human soul, which is called the intellect or the mind, is something incorporeal and subsistent.
Reply Obj. 1: "This particular thing" can be taken in two senses.
Firstly, for anything subsistent; secondly, for that which subsists, and is complete in a specific nature. The former sense excludes the inherence of an accident or of a material form; the latter excludes also the imperfection of the part, so that a hand can be called "this particular thing" in the first sense, but not in the second.
Therefore, as the human soul is a part of human nature, it can indeed be called "this particular thing," in the first sense, as being something subsistent; but not in the second, for in this sense, what is composed of body and soul is said to be "this particular thing."
Reply Obj. 2: Aristotle wrote those words as expressing not his own opinion, but the opinion of those who said that to understand is to be moved, as is clear from the context. Or we may reply that to operate _per se_ belongs to what exists _per se._ But for a thing to exist _per se,_ it suffices sometimes that it be not inherent, as an accident or a material form; even though it be part of something.
Nevertheless, that is rightly said to subsist _per se,_ which is neither inherent in the above sense, nor part of anything else. In this sense, the eye or the hand cannot be said to subsist _per se_; nor can it for that reason be said to operate _per se._ Hence the operation of the parts is through each part attributed to the whole.
For we say that man sees with the eye, and feels with the hand, and not in the same sense as when we say that what is hot gives heat by its heat; for heat, strictly speaking, does not give heat. We may therefore say that the soul understands, as the eye sees; but it is more correct to say that man understands through the soul.
Reply Obj. 3: The body is necessary for the action of the intellect, not as its origin of action, but on the part of the object; for the phantasm is to the intellect what color is to the sight. Neither does such a dependence on the body prove the intellect to be non-subsistent; otherwise it would follow that an animal is non-subsistent, since it requires external objects of the senses