THOMISTIC TERMS
1. Hylemorphism
2. Substance
3. Accident
4. Matter
5. Form
6. Potency/Potentiality
7. Act/Actuality
8. Subsistent
9. Change
10. Substantial Change
11. Accidental Change
12. Prime Matter
13. Substantial Form
14. Soul
15. Vegetative Soul
16. Sensitive Soul
17. Rational Soul
18. Genus
19. Species
20. Composite Being
Question 75: Of the Human Person,who is composed of a spiritual and a corporeal
substance:and in the first place,concerning what belongs to the essence
of the soul (7 articles)
Having treated of the spiritual and of the corporeal
creature, we now proceed to treat of the human person, who is composed of
a spiritual and corporeal substance. We shall treat first of the nature
of the human person, and secondly of his origin. Now the theologian considers
the nature of the person 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 the person, or is the person 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?
Article 1: Whether the soul is a body?
It would seem that the soul is a body:
1. 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.
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.
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 other hand, 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."
Response: 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.
Answer to argument 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.
Answer to argument 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 mu st 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.
Answer to argument 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.
Article 2: Whether the human soul is something subsistent?
It would seem that the human soul is not something subsistent.
1. 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.
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.
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 other hand, 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.
Response: 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.
Answer to argument 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."
Answer to argument 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.
Answer to argument 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 in order to perform its act of perception.
Article 4: Whether the soul is the person?
It would seem that the soul is the person.
1. For it is written (2 Cor. 4:16): "Though our outward
person is corrupted, yet the in ward person is renewed day by day."
But that which is within the person is the soul. Therefore the soul is the
inward person.
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 the person; for a human person is a person.
On the other hand, Augustine (De Civ. Dei xix, 3) commends
Varro as holding "that the person is not a mere soul, nor a mere body;
but both soul and body."
Response: The assertion "the soul is a person,"
can be taken in two senses. First, that the person is a soul; though this
particular person, 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 person to be composed of this soul, of this flesh, and
of these bones; so it belongs to the notion of person 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. It may also be understood in this sense, that
this soul is this person; 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 the person
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 person is a person. But it has been shown above (A3) 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 the person to be a soul making use
of the body.
Answer to argument 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.
Answer to argument 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.
Article 5: Whether the soul is composed of matter and form?
Objection 1. It would seem that the soul is composed of
matter and form. For potentiality is opposed to actuality. Now, whatsoever
things are in actuality participate of the First Act, which is God; by participation
of Whom, all things are good, are beings, and are living things, as is clear
from the teaching of Dionysius (Div. Nom. v). Therefore whatsoever things
are in potentiality participate of the first potentiality. But the first
potentiality is primary matter. Therefore, since the human soul is, after
a manner, in potentiality; which appears from the fact that sometimes a
man is potentially understanding; it seems that the human soul must participate
of primary matter, as part of itself.
Objection 2. Further, wherever the properties of matter
are found, there matter is. But the properties of matter are found in the
soul--namely, to be a subject, and to be changed, for it is a subject to
science, and virtue; and it changes from ignorance to knowledge and from
vice to virtue. Therefore matter is in the soul.
Objection 3. Further, things which have no matter, have
no cause of their existence, as the Philosopher says Metaph. viii (Did.
vii, 6). But the soul has a cause of its existence, since it is created
by God. Therefore the soul has matter.
Objection 4. Further, what has no matter, and is a form
only, is a pure act, and is infinite. But this belongs to God alone. Therefore
the soul has matter.
On the contrary, Augustine (Gen. ad lit. vii, 7,8,9) proves
that the soul was made neither of corporeal matter, nor of spiritual matter.
I answer that, The soul has no matter. We may consider
this question in two ways.
First, from the notion of a soul in general; for it belongs
to the notion of a soul to be the form of a body. Now, either it is a form
by virtue of itself, in its entirety, or by virtue of some part of itself.
If by virtue of itself in its entirety, then it is impossible that any part
of it should be matter, if by matter we understand something purely potential:
for a form, as such, is an act; and that which is purely potentiality cannot
be part of an act, since potentiality is repugnant to actuality as being
opposite thereto. If, however, it be a form by virtue of a part of itself,
then we call that part the soul: and that matter, which it actualizes first,
we call the "primary animate."
Secondly, we may proceed from the specific notion of the
human soul inasmuch as it is intellectual. For it is clear that whatever
is received into something is received according to the condition of the
recipient. Now a thing is known in as far as its form is in the knower.
But the intellectual soul knows a thing in its nature absolutely: for instance,
it knows a stone absolutely as a stone; and therefore the form of a stone
absolutely, as to its proper formal idea, is in the intellectual soul. Therefore
the intellectual soul itself is an absolute form, and not something composed
of matter and form. For if the intellectual soul were composed of matter
and form, the forms of things would be received into it as individuals,
and so it would only know the individual: just as it happens with the sensitive
powers which receive forms in a corporeal organ; since matter is the principle
by which forms are individualized. It follows, therefore, that the intellectual
soul, and every intellectual substance which has knowledge of forms absolutely,
is exempt from composition of matter and form.
Reply to Objection 1. The First Act is the universal principle
of all acts; because It is infinite, virtually "precontaining all things,"
as Dionysius says (Div. Nom. v). Wherefore things participate of It not
as a part of themselves, but by diffusion of Its processions. Now as potentiality
is receptive of act, it must be proportionate to act. But the acts received
which proceed from the First Infinite Act, and are participations thereof,
are diverse, so that there cannot be one potentiality which receives all
acts, as there is one act, from which all participated acts are derived;
for then the receptive potentiality would equal the active potentiality
of the First Act. Now the receptive potentiality in the intellectual soul
is other than the receptive potentiality of first matter, as appears from
the diversity of the things received by each. For primary matter receives
individual forms; whereas the intelligence receives absolute forms. Hence
the existence of such a potentiality in the intellectual soul does not prove
that the soul is composed of matter and form.
Reply to Objection 2. To be a subject and to be changed
belong to matter by reason of its being in potentiality. As, therefore,
the potentiality of the intelligence is one thing and the potentiality of
primary matter another, so in each is there a different reason of subjection
and change. For the intelligence is subject to knowledge, and is changed
from ignorance to knowledge, by reason of its being in potentiality with
regard to the intelligible species.
Reply to Objection 3. The form causes matter to be, and
so does the agent; wherefore the agent causes matter to be, so far as it
actualizes it by transmuting it to the act of a form. A subsistent form,
however, does not owe its existence to some formal principle, nor has it
a cause transmuting it from potentiality to act. So after the words quoted
above, the Philosopher concludes, that in things composed of matter and
form "there is no other cause but that which moves from potentiality
to act; while whatsoever things have no matter are simply beings at once."
[The Leonine edition has, "simpliciter sunt quod vere entia aliquid."
The Parma edition of St. Thomas's Commentary on Aristotle has, "statim
per se unum quiddam est . . . et ens quiddam."]
Reply to Objection 4. Everything participated is compared
to the participator as its act. But whatever created form be supposed to
subsist "per se," must have existence by participation; for "even
life," or anything of that sort, "is a participator of existence,"
as Dionysius says (Div. Nom. v). Now participated existence is limited by
the capacity of the participator; so that God alone, Who is His own existence,
is pure act and infinite. But in intellectual substances there is composition
of actuality and potentiality, not, indeed, of matter and form, but of form
and participated existence. Wherefore some say that they are composed of
that "whereby they are" and that "which they are"; for
existence itself is that by which a thing is.
Article 6: Whether the human soul is incorruptible?
It would seem that the human soul is corruptible.
1. For those things that have a like beginning and process
seemingly have a like end. But the beginning, by generation, of men is like
that of animals, for they are made from the earth. And the process of life
is alike in both; because "all things breathe alike, and man hath nothing
more than the beast," as it is written (Eccles. 3: 19). Therefore,
as the same text concludes, "the death of man and beast is one, and
the condition of both is equal." But the souls of brute animals are
corruptible. Therefore, also, the human soul is corruptible.
2. Further, whatever is out of nothing can return to nothingness;
because the end should correspond to the beginning. But as it is written
(Wis. 2:2), "We are born of nothing"; which is true, not only
of the body, but also of the soul. Therefore, as is concluded in the same
passage, "After this we shall be as if we had not been," even
as to our soul.
3. Further, nothing is without its own proper operation.
But the operation proper to the soul, which is to understand through a phantasm,
cannot be without the body. For the soul understands nothing without a phantasm;
and there is no phantasm without the body as the Philosopher says (De Anima
i, 1). Therefore the soul cannot survive the dissolution of the body.
On the other hand, Dionysius says (Div. Nom. iv) that human
souls owe to Divine goodness that they are "intellectual," and
that they have "an incorruptible substantial life."
Response: We must assert that the intellectual principle
which we call the human soul is incorruptible. For a thing may be corrupted
in two ways-per se, and accidentally. Now it is impossible for any substance
to be generated or corrupted accidentally, that is, by the generation or
corruption of something else. For generation and corruption belong to a
thing, just as existence belongs to it, which is acquired by generation
and lost by corruption. Therefore, whatever has existence per se cannot
be generated or corrupted except per se; while things which do not subsist,
such as accidents and material forms, acquire existence or lose it through
the generation or corruption of composite things. Now it was shown above
(aa. 2,3) that the souls of brutes are not self-subsistent, whereas the
human soul is; so that the souls of brutes are corrupted, when their bodies
are corrupted; while the human soul could not be corrupted unless it were
corrupted per se. This, indeed, is impossible, not only as regards the human
soul, but also as regards anything subsistent that is a form alone. For
it is clear that what belongs to a thing by virtue of itself is inseparable
from it; but existence belongs to a form, which is an act, by virtue of
itself. Wherefore matter acquires actual existence as it acquires the form;
while it is corrupted so far as the form is separated from it. But it is
impossible for a form to be separated from itself; and therefore it is impossible
for a subsistent form to cease to exist.
Granted even that the soul is composed of matter and form,
as some pretend, we should nevertheless have to maintain that it is incorruptible.
For corruption is found only where there is contrariety; since generation
and corruption are from contraries and into contraries. Wherefore the heavenly
bodies, since they have no matter subject to contrariety, are incorruptible.
Now there can be no contrariety in the intellectual soul; for it receives
according to the manner of its existence, and those things which it receives
are without contrariety; for the notions even of contraries are not themselves
contrary, since contraries belong to the same knowledge. Therefore it is
impossible for the intellectual soul to be corruptible.
Moreover we may take a sign of this from the fact that
everything naturally aspires to existence after its own manner. Now, in
things that have knowledge, desire ensues upon knowledge. The senses indeed
do not know existence, except under the conditions of "here" and
"now," whereas the intellect apprehends existence absolutely,
and for all time; so that everything that has an intellect naturally desires
always to exist. But a natural desire cannot be in vain. Therefore every
intellectual substance is incorruptible.
Answer to argument 1: Solomon reasons thus in the person
of the foolish, as expressed in the words of Wisdom 2. Therefore the saying
that man and animals have a like beginning in generation is true of the
body; for all animals alike are made of earth. But it is not true of the
soul. For the souls of brutes are produced by some power of the body; whereas
the human soul is produced by God. To signify this it is written as to other
animals: "Let the earth bring forth the living soul" (Gn. 1:24):
while of man it is written (Gn. 2:7) that "He breathed into his face
the breath of life." And so in the last chapter of Ecclesiastes (12:7)
it is concluded: "(Before) the dust return into its earth from whence
it was; and the spirit return to God Who gave it." Again the process
of life is alike as to the body, concerning which it is written (Eccles.
3:19): "All things breathe alike," and (Wis. 2:2), "The breath
in our nostrils is smoke." But the process is not alike of the soul;
for man is intelligent, whereas animals are not. Hence it is false to say:
"Man has nothing more than beasts." Thus death comes to both alike
as to the body, by not as to the soul.
Answer to argument 2: As a thing can be created by reason,
not of a passive potentiality, but only of the active potentiality of the
Creator, Who can produce something out of nothing, so when we say that a
thing can be reduced to nothing, we do not imply in the creature a potentiality
to non-existence, but in the Creator the power of ceasing to sustain existence.
But a thing is said to be corruptible because there is in it a potentiality
to non-existence.
Answer to argument 3: To understand through a phantasm
is the proper operation of the soul by virtue of its union with the body.
After separation from the body it will have another mode of understanding,
similar to other substances separated from bodies, as will appear later
on (Q89, A1).
Question 76
Of the Union of Body & Soul(8 Articles)
We now consider the union of the soul with the body; and
concerning this there are eight points of inquiry:
(1) Whether the intellectual principle is united to the
body as its form?
(2) Whether the intellectual principle is multiplied numerically
according to the number of bodies; or is there one intelligence for all
persons?
(3) Whether in the body the form of which is an intellectual
principle, there is some other soul?
(4) Whether in the body there is any other substantial
form?
(5) Of the qualities required in the body of which the
intellectual principle is the form?
(6) Whether it be united to such a body by means of another
body?
(7) Whether by means of an accident?
(8) Whether the soul is wholly in each part of the body?
Article 1: Whether the intellectual principle is united
to the body as its form?
It would seem that the intellectual principle is not united
to the body as its form:
1: For the Philosopher says (De Anima ii i, 4) that the
intellect is "separate," and that it is not the act of any body.
Therefore it is not united to the body as its form.
2. Further, every form is determined according to the nature
of the matter of which it is the form; otherwise no proportion would be
required between matter and form. Therefore if the intellect were united
to the body as its form, since every body has a determinate nature, it would
follow that the intellect has a determinate nature; and thus, it would not
be capable of knowing all things, as is clear from what has been said (Q75,
A2); which is contrary to the nature of the intellect. Therefore the intellect
is not united to the body as its form.
3. Further, whatever receptive power is an act of a body,
receives a form materially and individually; for what is received must be
received according to the condition of the receiver. But the form of the
thing understood is not received into the intellect materially and individually,
but rather immaterially and universally: otherwise the intellect would not
be capable of the knowledge of immaterial and universal objects, but only
of individuals, like the senses. Therefore the intellect is not united to
the body as its form.
4. Further, power and action have the same subject; for
the same subject is what can, and does, act. But the intellectual action
is not the action of a body, as appears from above (Q75, A2). Therefore
neither is the intellectual faculty a power of the body. But virtue or power
cannot be more abstract or more simple than the essence from which the faculty
or power is derived. Therefore neither is the substance of the intellect
the form of a body.
5. Further, whatever has per se existence is not united
to the body as its form; because a form is that by which a thing exists:
so that the very existence of a form does not belong to the form by itself.
But the intellectual principle has per se existence and is subsistent, as
was said above (Q75, A2). Therefore it is not united to the body as its
form.
6. Further, whatever exists in a thing by reason of its
nature exists in it always. But to be united to matter belongs to the form
by reason of its nature; because form is the act of matter, not by an accidental
quality, but by its own essence; otherwise matter and form would not make
a thing substantially one, but only accidentally one. Therefore a form cannot
be without its own proper matter. But the intellectual principle, since
it is incorruptible, as was shown above (Q75, A6), remains separate from
the body, after the dissolution of the body. Therefore the intellectual
principle is not united to the body as its form.
On the other hand, According to the Philosopher, Metaph.
viii (Did. vii 2), difference is derived from the form. But the difference
which constitutes man is "rational," which is applied to man on
account of his intellectual principle. Therefore the intellectual principle
is the form of man.
Response: We must assert that the intellect which is the
principle of intellectual operation is the form of the human body. For that
whereby primarily anything acts is a form of the thing to which the act
is to be attributed: for instance, that whereby a body is primarily healed
is health, and that whereby the soul knows primarily is knowledge; hence
health is a form of the body, and knowledge is a form of the soul. The reason
is because nothing acts except so far as it is in act; wherefore a thing
acts by that whereby it is in act. Now it is clear that the first thing
by which the body lives is the soul. And as life appears through various
operations in different degrees of living things, that whereby we primarily
perform each of all these vital actions is the soul. For the soul is the
primary principle of our nourishment, sensation, and local movement; and
likewise of our understanding. Therefore this principle by which we primarily
understand, whether it be called the intellect or the intellectual soul,
is the form of the body. This is the demonstration used by Aristotle (De
Anima ii, 2).
But if anyone says that the intellectual soul is not the
form of the body he must first explain how it is that this action of understanding
is the action of this particular man; for each one is conscious that it
is himself who understands. Now an action may be attributed to anyone in
three ways, as is clear from the Philosopher (Phys. v, 1); for a thing is
said to move or act, either by virtue of its whole self, for instance, as
a physician heals; or by virtue of a part, as a man sees by his eye; or
through an accidental quality, as when we say that something that is white
builds, because it is accidental to the builder to be white. So when we
say that Socrates or Plato understands, it is clear that this is not attributed
to him accidentally; since it is ascribed to him as man, which is predicated
of him essentially. We must therefore say either that Socrates understands
by virtue of his whole self, as Plato maintained, holding that man is an
intellectual soul; or that intelligence is a part of Socrates. The first
cannot stand, as was shown above (Q75, A4), for this reason, that it is
one and the same man who is conscious both that he understands, and that
he senses. But one cannot sense without a body: therefore the body must
be some part of man. It follows therefore that the intellect by which Socrates
understands is a part of Socrates, so that in some way it is united to the
body of Socrates.
The Commentator held that this union is through the intelligible
species, as having a double subject, in the possible intellect, and in the
phantasms which are in the corporeal organs. Thus through the intelligible
species the possible intellect is linked to the body of this or that particular
man. But this link or union does not sufficiently explain the fact, that
the act of the intellect is the act of Socrates. This can be clearly seen
from comparison with the sensitive faculty, from which Aristotle proceeds
to consider things relating to the intellect. For the relation of phantasms
to the intellect is like the relation of colors to the sense of sight, as
he says De Anima iii, 5,7. Therefore, as the species of colors are in the
sight, so are the species of phantasms in the possible intellect. Now it
is clear that because the colors, the images of which are in the sight,
are on a wall, the action of seeing is not attributed to the wall: for we
do not say that the wall sees, but rather that it is seen. Therefore, from
the fact that the species of phantasms are in the possible intellect, it
does not follow that Socrates, in whom are the phantasms, understands, but
that he or his phantasms are understood.
Some, however, tried to maintain that the intellect is
united to the body as its motor; and hence that the intellect and body form
one thing so that the act of the intellect could be attributed to the whole.
This is, however, absurd for many reasons. First, because the intellect
does not move the body except through the appetite, the movement of which
presupposes the operation of the intellect. The reason therefore why Socrates
understands is not because he is moved by his intellect, but rather, contrariwise,
he is moved by his intellect because he understands. Secondly, because since
Socrates is an individual in a nature of one essence composed of matter
and form, if the intellect be not the form, it follows that it must be outside
the essence, and then the intellect is the whole Socrates as a motor to
the thing moved. Whereas the act of intellect remains in the agent, and
does not pass into something else, as does the action of heating. Therefore
the action of understanding cannot be attributed to Socrates for the reason
that he is moved by his intellect. Thirdly, because the action of a motor
is never attributed to the thing moved, except as to an instrument; as the
action of a carpenter to a saw. Therefore if understanding is attributed
to Socrates, as the action of what moves him, it follows that it is attributed
to him as to an instrument. This is contrary to the teaching of the Philosopher,
who holds that understanding is not possible through a corporeal instrument
(De Anima iii, 4). Fourthly, because, although the action of a part be attributed
to the whole, as the action of the eye is attributed to a man; yet it is
never attributed to another part, except perhaps indirectly; for we do not
say that the hand sees because the eye sees. Therefore if the intellect
and Socrates are united in the above manner, the action of the intellect
cannot be attributed to Socrates. If, however, Socrates be a whole composed
of a union of the intellect with whatever else belongs to Socrates, and
still the intellect be united to those other things only as a motor, it
follows that Socrates is not one absolutely, and consequently neither a
being absolutely, for a thing is a being according as it is one.
There remains, therefore, no other explanation than that
given by Aristotle-namely, that this particular man understands, because
the intellectual principle is his form. Thus from the very operation of
the intellect it is made clear that the intellectual principle is united
to the body as its form.
The same can be clearly shown from the nature of the human
species. For the nature of each thing is shown by its operation. Now the
proper operation of man as man is to understand; because he thereby surpasses
all other animals. Whence Aristotle concludes (Ethic. x, 7) that the ultimate
happiness of man must consist in this operation as properly belonging to
him. Man must therefore derive his species from that which is the principle
of this operation. But the species of anything is derived from its form.
It follows therefore that the intellectual principle is the proper form
of man.
But we must observe that the nobler a form is, the more
it rises above corporeal matter, the less it is merged in matter, and the
more it excels matter by its power and its operation; hence we find that
the form of a mixed body has another operation not caused by its elemental
qualities. And the higher we advance in the nobility of forms, the more
we find that the power of the form excels the elementary matter; as the
vegetative soul excels the form of the metal, and the sensitive soul excels
the vegetative soul. Now the human soul is the highest and noblest of forms.
Wherefore it excels corporeal matter in its power by the fact that it has
an operation and a power in which corporeal matter has no share whatever.
This power is called the intellect.
It is well to remark that if anyone holds that the soul
is composed of matter and form, it would follow that in no way could the
soul be the form of the body. For since the form is an act, and matter is
only in potentiality, that which is composed of matter and form cannot be
the form of another by virtue of itself as a whole. But if it is a form
by virtue of some part of itself, then that part which is the form we call
the soul, and that of which it is the form we call the "primary animate,"
as was said above (Q75, A5).
Answer to argument 1: As the Philosopher says (Phys. ii,
2), the ultimate natural form to which the consideration of the natural
philosopher is directed is indeed separate; yet it exists in matter. He
proves this from the fact that "man and the sun generate man from matter."
It is separate indeed according to its intellectual power, because the intellectual
power does not belong to a corporeal organ, as the power of seeing is the
act of the eye; for understanding is an act which cannot be performed by
a corporeal organ, like the act of seeing. But it exists in matter so far
as the soul itself, to which this power belongs, is the form of the body,
and the term of human generation. And so the Philosopher says (De Anima
iii) that the intellect is separate, because it is not the faculty of a
corporeal organ.
From this it is clear how to answer the Second and Third
Objections: since, in order that man may be able to understand all things
by means of his intellect, and that his intellect may understand immaterial
things and universals, it is sufficient that the intellectual power be not
the act of the body.
Answer to argument 4: The human soul, by reason of its
perfection, is not a form merged in matter, or entirely embraced by matter.
Therefore there is nothing to prevent some power thereof not being the act
of the body, although the soul is essentially the form of the body.
Answer to argument 5: The soul communicates that existence
in which it subsists to the corporeal matter, out of which and the intellectual
soul there results unity of existence; so that the existence of the whole
composite is also the existence of the soul. This is not the case with other,
non-subsistent forms. For this reason the human soul retains its own existence
after the dissolution of the body; whereas it is not so with other forms.
Answer to argument 6: To be united to the body belongs
to the soul by reason of itself, as it belongs to a light body by reason
of it self to be raised up. And as a light body remains light, when removed
from its proper place, retaining meanwhile an aptitude and an inclination
for its proper place; so the human soul retains its proper existence when
separated from the body, having an aptitude and a natural inclination to
be united to the body.
Article 2: Whether the intellectual principle is multiplied
according to the number of bodies?
It would seem that the intellectual principle is not multiplied
according to the number of bodies, but that there is one intellect in all
persons.
1. For an immaterial substance is not multiplied in number
within one species. But the human soul is an immaterial substance; since
it is not composed of matter and form as was shown above (Q75, A5). Therefore
there are not many human souls in one species. But all men are of one species.
Therefore there is but one intellect in all men.
2. Further, when the cause is removed, the effect is also
removed. Therefore, if human souls were multiplied according to the number
of bodies, it follows that the bodies being removed, the number of souls
would not remain; but from all the souls there would be but a single remainder.
This is heretical; for it would do away with the distinction of rewards
and punishments.
3. Further, if my intellect is distinct from your intellect,
my intellect is an individual, and so is yours; for individuals are things
which differ in number but agree in one species. Now whatever is received
into anything must be received according to the condition of the receiver.
Therefore the species of things would be received individually into my intellect,
and also into yours: which is contrary to the nature of the intellect which
knows universals.
4. Further, the thing understood is in the intellect which
understands. If, therefore, my intellect is distinct from yours, what is
understood by me must be distinct from what is understood by you; and consequently
it will be reckoned as something individual, and be only potentially something
understood; so that the common intention will have to be abstracted from
both; since from things diverse something intelligible common to them may
be abstracted. But this is contrary to the nature of the intellect; for
then the intellect would seem not to be distinct from the imagination. It
seems, therefore, to follow that there is one intellect in all men.
5. Further, when the disciple receives knowledge from the
master, it cannot be said that the master's knowledge begets knowledge in
the disciple, because then also knowledge would be an active form, such
as heat is, which is clearly false. It seems, therefore, that the same individual
knowledge which is in the master is communicated to the disciple; which
cannot be, unless there is one intellect in both. Seemingly, therefore,
the intellect of the disciple and master is but one; and, consequently,
the same applies to all men.
6. Further, Augustine (De Quant. Animae xxxii) says: "If
I were to say that there are many human souls, I should laugh at myself."
But the soul seems to be one chiefly on account of the intellect. Therefore
there is one intellect of all men.
On the other hand, The Philosopher says (Phys. ii, 3) that
the relation of universal causes to universals is like the relation of particular
causes to individuals. But it is impossible that a soul, one in species,
should belong to animals of different species. Therefore it is impossible
that one individual intellectual soul should belong to several individuals.
Response: It is absolutely impossible for one intellect
to belong to all men. This is clear if, as Plato maintained, man is the
intellect itself. For it would follow that Socrates and Plato are one man;
and that they are not distinct from each other, except by something outside
the essence of each. The distinction between Socrates and Plato would be
no other than that of one man with a tunic and another with a cloak; which
is quite absurd.
It is likewise clear that this is impossible if, according
to the opinion of Aristotle (De Anima ii, 2), it is supposed that the intellect
is a part or a power of the soul which is the form of man. For it is impossible
for many distinct individuals to have one form, as it is impossible for
them to have one existence, for the form is the principle of existence.
Again, this is clearly impossible, whatever one may hold
as to the manner of the union of the intellect to this or that man. For
it is manifest that, supposing there is one principal agent, and two instruments,
we can say that there is one agent absolutely, but several actions; as when
one man touches several things with his two hands, there will be one who
touches, but two contacts. If, on the contrary, we suppose one instrument
and several principal agents, we might say that there are several agents,
but one act; for example, if there be many drawing a ship by means of a
rope; there will be many drawing, but one pull. If, however, there is one
principal agent, and one instrument, we say that there is one agent and
one action, as when the smith strikes with one hammer, the re is one striker
and one stroke. Now it is clear that no matter how the intellect is united
or coupled to this or that man, the intellect has the precedence of all
the other things which appertain to man; for the sensitive powers obey the
intellect, and are at its service. Therefore, if we suppose two men to have
several intellects and one sense-for instance, if two men had one eye-there
would be several seers, but one sight. But if there is one intellect, no
matter how diverse may be all those things of which the intellect makes
use as instruments, in no way is it possible to say that Socrates and Plato
are otherwise than one understanding man. And if to this we add that to
understand, which is the act of the intellect, is not affected by any organ
other than the intellect itself; it will further follow that there is but
one agent and one action: that is to say that all men are but one "understander,"
and have but one act of understanding, in regard, that is, of one intelligible
object.
However, it would be possible to distinguish my intellectual
action form yours by the distinction of the phantasms-that is to say, were
there one phantasm of a stone in me, and another in you-if the phantasm
itself, as it is one thing in me and another in you, were a form of the
possible intellect; since the same agent according to divers forms produces
divers actions; as, according to divers forms of things with regard to the
same eye, there are divers visions. But the phantasm itself is not a form
of the possible intellect; it is the intelligible species abstracted from
the phantasm that is a form. Now in one intellect, from different phantasms
of the same species, only one intelligible species is abstracted; as appears
in one man, in whom there may be different phantasms of a stone; yet from
all of them only one intelligible species of a stone is abstracted; by which
the intellect of that one man, by one operation, understands the nature
of a stone, notwithstanding the diversity of phantasms. Therefore, if there
were one intellect for all men, the diversity of phantasms which are in
this one and that one would not cause a diversity of intellectual operation
in this man and that man. It follows, therefore, that it is altogether impossible
and unreasonable to maintain that there exists one intellect for all men.
Answer to argument 1: Although the intellectual soul, like
an angel, has no matter from which it is produced, yet it is the form of
a certain matter; in which it is unlike an angel. Therefore, according to
the division of matter, there are many souls of one species; while it is
quite impossible for many angels to be of one species.
Answer to argument 2: Everything has unity in the same
way that it has being; consequently we must judge of the multiplicity of
a thing as we judge of its being. Now it is clear that the intellectual
soul, by virtue of its very being, is united to the body as its form; yet,
after the dissolution of the body, the intellectual soul retains its own
being. In like manner the multiplicity of souls is in proportion to the
multiplicity of the bodies; yet, after the dissolution of the bodies, the
souls retain their multiplied being .
Answer to argument 3: Individuality of the intelligent
being, or of the species whereby it understands, does not exclude the understanding
of universals; otherwise, since separate intellects are subsistent substances,
and consequently individual, they could not understand universals. But the
materiality of the knower, and of the species whereby it knows, impedes
the knowledge of the universal. For as every action is according to the
mode of the form by which the agent acts, as heating is according to the
mode of the heat; so knowledge is according to the mode of the species by
which the knower knows. Now it is clear that common nature becomes distinct
and multiplied by reason of the individuating principles which come from
the matter. Therefore if the form, which is the means of knowledge, is material-that
is, not abstracted from material conditions-its likeness to the nature of
a species or genus will be ac cording to the distinction and multiplication
of that nature by means of individuating principles; so that knowledge of
the nature of a thing in general will be impossible. But if the species
be abstracted from the conditions of individual matter, there will be a
likeness of the nature without those things which make it distinct and multiplied;
thus there will be knowledge of the universal. Nor does it matter, as to
this particular point, whether there be one intellect or many; because,
even if there were but one, it would necessarily be an individual intellect,
and the species whereby it understands, an individual species.
Answer to argument 4: Whether the intellect be one or many,
what is understood is one; for what is understood is in the intellect, not
according to its own nature, but according to its likeness; for "the
stone is not in the soul, but its likeness is," as is said, De Anima
iii, 8. Yet it is the stone which is understood, not the likeness of the
stone; except by a reflection of the intellect on itself: otherwise, the
objects of sciences would not be things, but only intelligible species.
Now it happens that different things, according to different forms, are
likened to the same thing. And since knowledge is begotten according to
the assimilation of the knower to the thing known, it follows that the same
thing may happen to be known by several knowers; as is apparent in regard
to the senses; for several see the same color, according to different likenesses.
In the same way several intellects understand one object understood. But
there is this difference, according to the opinion of Aristotle, between
the sense and the intelligence-that a thing is perceived by the sense according
to the disposition which it has outside the soul-that is, in its individuality;
whereas the nature of the thing understood is indeed outside the soul, but
the mode according to which it exists outside the soul is not the mode according
to which it is understood. For the common nature is understood as apart
from the individuating principles; whereas such is not its mode of existence
outside the soul. But, according to the opinion of Plato, the thing understood
exists outside the soul in the same condition as those under which it is
understood; for he supposed that the natures of things exist separate from
matter.
Answer to argument 5: One knowledge exists in the disciple
and another in the master. How it is caused will be shown later on (Q117,
A1).
Answer to argument 6: Augustine denies a plurality of souls,
that would involve a plurality of species.
Article 3: Whether besides
the intellectual soul there are in the person other souls essentially different
from one another?
It would seem that besides the intellectual soul there
are in the person other souls essentially different from one another, such
as the sensitive soul and the nutritive soul.
1. For corruptible and incorruptible are not of the same
substance. But the intellectual soul is incorruptible; whereas the other
souls, as the sensitive and the nutritive, are corruptible, as was shown
above (Q75, A6). Therefore in the person the essence of the intellectual
soul, the sensitive soul, and the nutritive soul, cannot be the same.
2. Further, if it be said that the sensitive soul in the
person is incorruptible; on the contrary, "corruptible and incorruptible
differ generically," says the Philosopher, Metaph. x (Did. ix, 10).
But the sensitive soul in the horse, the lion, and other brute animals,
is corruptible. If, therefore, in man it be incorruptible, the sensitive
soul in the person and brute animals will not be of the same "genus."
Now an animal is so called from its having a sensitive soul; and, therefore,
"animal" will not be one genus common to persons and other animals,
which is absurd.
3. Further, the Philosopher says, Metaph. viii (Did. vii,
2), that the genus is taken from the matter, and difference from the form.
But "rational," which is the difference constituting the person,
is taken from the intellectual soul; while he is called "animal"
by reason of his having a body animated by a sensitive soul. Therefore the
intellectual soul may be compared to the body animated by a sensitive soul,
as form to matter. Therefore in man the intellectual soul is not essentially
the same as the sensitive soul, but presupposes it as a material subject.
On the other hand, It is said in the book De Ecclesiasticis
Dogmatibus xv: "Nor do we say that there are two souls in one person,
as James and other Syrians write; one, animal, by which the body is animated,
and which is mingled with the blood; the other, spiritual, which obeys the
reason; but we say that it is one and the same soul in the person, that
both gives life to the body by being united to it, and orders itself by
its own reasoning."
Response: Plato held that there were several souls in one
body, distinct even as to organs, to which souls he referred the different
vital actions, saying that the nutritive power is in the liver, the concupiscible
in the heart, and the power of knowledge in the brain. Which opinion is
rejected by Aristotle (De Anima ii, 2), with regard to those parts of the
soul which use corporeal organs; for this reason, that in those animals
which continue to live when they have been divided in each part are observed
the operations of the soul, as sense and appetite. Now this would not be
the case if the various principles of the soul's operations were essentially
different, and distributed in the various parts of the body. But with regard
to the intellectual part, he seems to leave it in doubt whether it be "only
logically" distinct from the other parts of the soul, "or also
locally."
The opinion of Plato might be maintained if, as he held,
the soul was supposed to be united to the body, not as its form, but as
its motor. For it involves nothing unreasonable that the same movable thing
be moved by several motors; and still less if it be moved according to its
various parts. If we suppose, however, that the soul is united to the body
as its form, it is quite impossible for several essentially different souls
to be in one body. This can be made clear by three different reasons.
In the first place, an animal would not be absolutely one,
in which there were several souls. For nothing is absolutely one except
by one form, by which a thing has existence: because a thing has from the
same source both existence and unity; and therefore things which are denominated
by various forms are not absolutely one; as, for instance, "a white
man." If, therefore, man were 'living' by one form, the vegetative
soul, and 'animal' by another form, the sensitive soul, and "man"
by another form, the intellectual soul, it would follow that man is not
absolutely one. Thus Aristotle argues, Metaph. viii (Did. vii, 6), against
Plato, that if the idea of an animal is distinct from the idea of a biped,
then a biped animal is not absolutely one. For this reason, against those
who hold that there are several souls in the body, he asks (De Anima i,
5), "what contains them?"-that is, what makes them one? It cannot
be said that they are united by the one body; because rather does the soul
contain the body and make it one, than the reverse .
Secondly, this is proved to be impossible by the manner
in which one thing is predicated of another. Those things which are derived
from various forms are predicated of one another, either accidentally, (if
the forms are not ordered to one another, as when we say that something
white is sweet), or essentially, in the second manner of essential predication,
(if the forms are ordered one to another, the subject belonging to the definition
of the predicate; as a surface is presupposed to color; so that if we say
that a body with a surface is colored, we have the second manner of essential
predication.) Therefore, if we have one form by which a thing is an animal,
and another form by which it is a man, it follows either that one of these
two things could not be predicated of the other, except accidentally, supposing
these two forms not to be ordered to one another-or that one would be predicated
of the other according to the second manner of essential predication, if
one soul be presupposed to the other. But both of these consequences are
clearly false: because "animal" is predicated of man essentially
and not accidentally; and man is not part of the definition of an animal,
but the other way about. Therefore of necessity by the same form a thing
is animal and man; otherwise man would not really be the thing which is
an animal, so that animal can be essentially predicated of man.
Thirdly, this is shown to be impossible by the fact that
when one operation of the soul is intense it impedes another, which could
never be the case unless the principle of action were essentially one.
We must therefore conclude that in man the sensitive soul,
the intellectual soul, and the nutritive soul are numerically one soul.
This can easily be explained, if we consider the differences of species
and forms. For we observe that the species and forms of things differ from
one another, as the perfect and imperfect; as in the order of things, the
animate are more perfect than the in animate, and animals more perfect than
plants, and man than brute animals; and in each of these genera there are
various degrees. For this reason Aristotle, Metaph. viii (Did. vii, 3),
compares the species of things to numbers, which differ in species by the
addition or subtraction of unity. And (De Anima ii, 3) he compares the various
souls to the species of figures, one of which contains another; as a pentagon
contains and exceeds a tetragon. Thus the intellectual soul contains virtually
whatever belongs to the sensitive soul of brute animals, and to the nutritive
souls of plants. Therefore, as a surface which is of a pentagonal shape,
is not tetragonal by one shape, and pentagonal by another-since a tetragonal
shape would be superfluous as contained in the pentagonal-so neither is
Socrates a man by one soul, and animal by another; but by one and the same
soul he is both animal and man.
Answer to argument 1: The sensitive soul is incorruptible,
not by reason of its being sensitive, but by reason of its being intellectual.
When, therefore, a soul is sensitive only, it is corruptible; but when with
sensibility it has also intellectuality, it is incorruptible. For although
sensibility does not give incorruptibility, yet it cannot deprive intellectuality
of its incorruptibility.
Answer to argument 2: Not forms, but composites, are classified
either generically or specifically. Now man is corruptible like other animals.
And so the difference of corruptible and incorruptible which is on the part
of the forms does not involve a generic difference between man and the other
animals.
Answer to argument 3: The embryo has first of all a soul
which is merely sensitive, and when this is removed, it is supplanted by
a more perfect soul, which is both sensitive and intellectual: as will be
shown further on (Q118, A2, ad 2).
Answer to argument 4: We must not consider the diversity
of natural things as proceeding from the various logical notions or intentions,
which flow from our manner of understanding, because reason can apprehend
one and the same thing in various ways. Therefore since, as we have said,
the intellectual soul contains virtually what belongs to the sensitive soul,
and something more, reason can consider separately what belongs to the power
of the sensitive soul, as something imperfect and material. And because
it observes that this is something common to man and to other animals, it
forms thence the notion of the "genus"; while that wherein the
intellectual soul exceeds the sensitive soul, it takes as formal and perfecting;
thence it gathers the "difference" of man.
Article 4: Whether
in the person there is another form besides the intellectual soul?
It would seem that in the person there is another form
besides the intellectual soul. For the Philosopher says (De Anima ii, 1),
that "the soul is the act of a physical body which has life potentially."
Therefore the soul is to the body as a form of matter. But the body has
a substantial form by which it is a body. Therefore some other substantial
form in the body precedes the soul.
2. Further, the person moves himself as every animal does.
Now everything that moves itself is divided into two parts, of which one
moves, and the other is moved, as the Philosopher proves (Phys. viii, 5).
But the part which moves is the soul. Therefore the other part must be such
that it can be moved. But primary matter cannot be moved (Phys. v, 1), since
it is a being only potentially; indeed everything that is moved is a body.
Therefore in the person and in every animal there must be another substantial
form, by which the body is constituted.
3. Further, the order of forms depends on their relation
to primary matter; for "before" and "after" apply by
comparison to some beginning. Therefore if there were not in the person
some other substantial form besides the rational soul, and if this were
to inhere immediately to primary matter; it would follow that it ranks among
the most imperfect forms which inhere to matter immediately.
4. Further, the human body is a mixed body. Now mingling
does not result from matter alone; for then we should have mere corruption.
Therefore the forms of the elements must remain in a mixed body; and these
are substantial forms. Therefore in the human body there are other substantial
forms besides the intellectual soul.
On the other hand, Of one thing there is but one substantial
being. But the substantial form gives substantial being. Therefore of one
thing there is but one substantial form. But the soul is the substantial
form of the person. Therefore it is impossible for there to be in the person
another substantial form besides the intellectual soul.
Response: If we suppose that the intellectual soul is not
united to the body as its form, but only as its motor, as the Platonists
maintain, it would necessarily follow that in the person there is another
substantial form, by which the body is established in its being as movable
by the soul. If, however, the intellectual soul be united to the body as
its substantial form, as we have said above (A1), it is impossible for another
substantial form besides the intellectual soul to be found in the person.
In order to make this evident, we must consider that the
substantial form differs from the accidental form in this, that the accidental
form does not make a thing to be "simply," but to be "such,"
as heat does not make a thing to be simply, but only to be hot.
Therefore by the coming of the accidental form a thing
is not said to be made or generated simply, but to be made such, or to be
in some particular condition; and in like manner, when an accidental form
is removed, a thing is said to be corrupted, not simply,but relatively.
Now the substantial form gives being simply; therefore by its coming a thing
is said to be generated simply; and by its removal to be corrupted simply.
For this reason, the old natural philosophers, who held that primary matter
was some actual being-for instance, fire or air, or something of that sort-maintained
that nothing is generated simply, or corrupted simply; and st ted that "every
becoming is nothing but an alteration," as we read, Phys. i, 4. Therefore,
if besides the intellectual soul there pre-existed in matter another substantial
form by which the subject of the soul were made an actual being, it would
follow that the soul does not give being simply; and consequently that it
is not the substantial form: and so at the advent of the soul there would
not be simple generation; nor at its removal simple corruption, all of which
is clearly false.
Whence we must conclude, that there is no other substantial
form in the person besides the intellectual soul; and that the soul, as
it virtually contains the sensitive and nutritive souls, so does it virtually
contain all inferior forms, and itself alone does whatever the imperfect
forms do in other things. The same is to be said of the sensitive soul in
brute animals, and of the nutritive soul in plants, and universally of all
more perfect forms with regard to the imperfect.
Answer to argument 1: Aristotle does not say that the soul
is the act of a body only, but "the act of a physical organic body
which has life potentially"; and that this potentiality "does
not reject the soul." Whence it is clear that when the soul is called
the act, the soul itself is included; as when we say that heat is the act
of what is hot, and light of what is lucid; not as though lucid and light
were two separate things, but because a thing is made lucid by the light.
In like manner, the soul is said to be the "act of a body," etc.,
because by the soul it is a body, and is organic, and has life potentially.
Yet the first act is said to be in potentiality to the second act, which
is operation; for such a potentiality "does not reject"-that is,
does not exclude-the soul.
Answer to argument 2: The soul does not move the body by
its essence, as the form of the body, but by the motive power, the act of
which presupposes the body to be already actualized by the soul: so that
the soul by its motive power is the part which moves; and the animate body
is the part moved.
Answer to argument 3: We observe in matter various degrees
of perfection, as existence, living, sensing, and understanding. Now what
is added is always more perfect. Therefore that form which gives matter
only the first degree of perfection is the most imperfect; while that form
which gives the first, second, and third degree, and so on, is the most
perfect: and yet it inheres to matter immediately.
Answer to argument 4: Avicenna held that the substantial
forms of the elements remain entire in the mixed body; and that the mixture
is made by the contrary qualities of the elements being reduced to an average.
But this is impossible, because the various forms of the elements must necessarily
be in various parts of matter; for the distinction of which we must suppose
dimensions, without which matter cannot be divisible. Now matter subject
to dimension is not to be found except in a body. But various bodies cannot
be in the same place. Whence it follows that elements in the mixed body
would be distinct as to situation. And then there would not be a real mixture
which is in respect of the whole; but only a mixture apparent to sense,
by the juxtaposition of particles.
Averroes maintained that the forms of elements, by reason
of their imperfection, are a medium between accidental and substantial forms,
and so can be "more" or "less"; and therefore in the
mixture they are modified and reduced to an average, so that one fo rm emerges
from them. But this is even still more impossible. For the substantial being
of each thing consists in something indivisible, and every addition and
subtraction varies the species, as in numbers, as stated in Metaph. viii
(Did. vii, 3); and consequently it is impossible for any substantial form
to receive "more" or "less." Nor is it less impossible
for anything to be a medium between substance and accident.
Therefore we must say, in accordance with the Philosopher
(De Gener. i, 10), that the forms of the elements remain in the mixed body,
not actually but virtually. For the proper qualities of the elements remain,
though modified; and in them is the power of the elementary forms. This
quality of the mixture is the proper disposition for the substantial form
of the mixed body; for instance, the form of a stone, or of any sort of
soul.