50
OF THE SUBSTANCE OF THE ANGELS ABSOLUTELY CONSIDERED
Now we consider the distinction of corporeal and spiritual creatures: firstly, the
purely spiritual creature which in Holy Scripture is called angel; secondly, the creature
wholly corporeal; thirdly, the composite creature, corporeal and spiritual, which is man.
Concerning the angels, we consider first what belongs to their substance; secondly,
what belongs to their intellect; thirdly, what belongs to their will; fourthly, what
belongs to their creation.
Their substance we consider absolutely and in relation to corporeal things.
Concerning their substance absolutely considered, there are five points of inquiry:
(1) Whether there is any entirely spiritual creature, altogether incorporeal?
(2) Supposing that an angel is such, we ask whether it is composed of matter and form?
(3) We ask concerning their number.
(4) Of their difference from each other.
(5) Of their immortality or incorruptibility.

ARTICLE 1
Whether an angel is altogether incorporeal?
Objection 1
It would seem that an angel is not entirely incorporeal. For what is incorporeal
only as regards ourselves, and not in relation to God, is not absolutely incorporeal. But
Damascene says (De Fide Orth. ii) that "an angel is said to be incorporeal and
immaterial as regards us; but compared to God it is corporeal and material. Therefore he
is not simply incorporeal."
Objection 2
Further, nothing is moved except a body, as the Philosopher says (Phys. vi, text
32). But Damascene says (De Fide Orth. ii) that "an angel is an ever movable
intellectual substance." Therefore an angel is a corporeal substance.
Objection 3
Further, Ambrose says (De Spir. Sanct. i, 7): "Every creature is limited
within its own nature." But to be limited belongs to bodies. Therefore, every
creature is corporeal. Now angels are God's creatures, as appears from Ps. 148:2:
"Praise ye" the Lord, "all His angels"; and, farther on (verse 4),
"For He spoke, and they were made; He commanded, and they were created."
Therefore angels are corporeal.
On the contrary
On the contrary, It is said (Ps. 103:4): "Who makes His angels spirits."
Body
I answer that, There must be some incorporeal creatures. For what is principally
intended by God in creatures is good, and this consists in assimilation to God Himself.
And the perfect assimilation of an effect to a cause is accomplished when the effect
imitates the cause according to that whereby the cause produces the effect; as heat makes
heat. Now, God produces the creature by His intellect and will (Q14, ARTICLE 8; Q19,
ARTICLE 4 ). Hence the perfection of the universe requires that there should be
intellectual creatures. Now intelligence cannot be the action of a body, nor of any
corporeal faculty; for every body is limited to "here" and "now."
Hence the perfection of the universe requires the existence of an incorporeal creature.
The ancients, however, not properly realizing the force of intelligence, and failing to
make a proper distinction between sense and intellect, thought that nothing existed in the
world but what could be apprehended by sense and imagination. And because bodies alone
fall under imagination, they supposed that no being existed except bodies, as the
Philosopher observes (Phys. iv, text 52,57). Thence came the error of the Sadducees, who
said there was no spirit (Acts 23:8).
But the very fact that intellect is above sense is a reasonable proof that there are
some incorporeal things comprehensible by the intellect alone.
Reply to Objection 1
Incorporeal substances rank between God and corporeal creatures. Now the
medium compared to one extreme appears to be the other extreme, as what is tepid compared
to heat seems to be cold; and thus it is said that angels, compared to God, are material
and corporeal, not, however, as if anything corporeal existed in them.
Reply to Objection 2
Movement is there taken in the sense in which it is applied to
intelligence and will. Therefore an angel is called an ever mobile substance, because he
is ever actually intelligent, and not as if he were sometimes actually and sometimes
potentially, as we are. Hence it is clear that the objection rests on an equivocation.
Reply to Objection 3
To be circumscribed by local limits belongs to bodies only; whereas to be
circumscribed by essential limits belongs to all creatures, both corporeal and spiritual.
Hence Ambrose says (De Spir. Sanct. i, 7) that "although some things are not
contained in corporeal place, still they are none the less circumscribed by their
substance."

ARTICLE 2
Whether an angel is composed of matter and form?
Objection 1
It would seem that an angel is composed of matter and form. For everything which
is contained under any genus is composed of the genus, and of the difference which added
to the genus makes the species. But the genus comes from the matter, and the difference
from the form (Metaph. xiii, text 6). Therefore everything which is in a genus is composed
of matter and form. But an angel is in the genus of substance. Therefore he is composed of
matter and form.
Objection 2
Further, wherever the properties of matter exist, there is matter. Now the
properties of matter are to receive and to substand; whence Boethius says (De
Trin.) that
"a simple form cannot be a subject": and the above properties are found in the
angel. Therefore an angel is composed of matter and form.
Objection 3
Further, form is act. So what is form only is pure act. But an angel is not pure
act, for this belongs to God alone. Therefore an angel is not form only, but has a form in
matter.
Objection 4
Further, form is properly limited and perfected by matter. So the form which is
not in matter is an infinite form. But the form of an angel is not infinite, for every
creature is finite. Therefore the form of an angel is in matter.
On the contrary
On the contrary, Dionysius says (Div. Nom. iv): "The first creatures are
understood to be as immaterial as they are incorporeal."
Body
I answer that, Some assert that the angels are composed of matter and form; which
opinion Avicebron endeavored to establish in his book of the Fount of Life. For he
supposes that whatever things are distinguished by the intellect are really distinct. Now
as regards incorporeal substance, the intellect apprehends that which distinguishes it
from corporeal substance, and that which it has in common with it. Hence he concludes that
what distinguishes incorporeal from corporeal substance is a kind of form to it, and
whatever is subject to this distinguishing form, as it were something common, is its
matter. Therefore, he asserts the universal matter of spiritual and corporeal things is
the same; so that it must be understood that the form of incorporeal substance is
impressed in the matter of spiritual things, in the same way as the form of quantity is
impressed in the matter of corporeal things.
But one glance is enough to show that there cannot be one matter of spiritual and of
corporeal things. For it is not possible that a spiritual and a corporeal form should be
received into the same part of matter, otherwise one and the same thing would be corporeal
and spiritual. Hence it would follow that one part of matter receives the corporeal form,
and another receives the spiritual form. Matter, however, is not divisible into parts
except as regarded under quantity; and without quantity substance is indivisible, as
Aristotle says (Phys. i, text 15). Therefore it would follow that the matter of spiritual
things is subject to quantity; which cannot be. Therefore it is impossible that corporeal
and spiritual things should have the same matter.
It is, further, impossible for an intellectual substance to have any kind of matter.
For the operation belonging to anything is according to the mode of its substance. Now to
understand is an altogether immaterial operation, as appears from its object, whence any
act receives its species and nature. For a thing is understood according to its degree of
immateriality; because forms that exist in matter are individual forms which the intellect
cannot apprehend as such. Hence it must be that every individual substance is altogether
immaterial.
But things distinguished by the intellect are not necessarily distinguished in reality;
because the intellect does not apprehend things according to their mode, but according to
its own mode. Hence material things which are below our intellect exist in our intellect
in a simpler mode than they exist in themselves. Angelic substances, on the other hand,
are above our intellect; and hence our intellect cannot attain to apprehend them, as they
are in themselves, but by its own mode, according as it apprehends composite things; and
in this way also it apprehends God (Q3).
Reply to Objection 1
It is difference which constitutes the species. Now everything is
constituted in a species according as it is determined to some special grade of being
because "the species of things are like numbers," which differ by addition and
subtraction of unity, as the Philosopher says (Metaph. viii, text 10). But in material
things there is one thing which determines to a special grade, and that is the form; and
another thing which is determined, and this is the matter; and hence from the latter the
"genus" is derived, and from the former the "difference." Whereas in
immaterial things there is no separate determinator and thing determined; each thing by
its own self holds a determinate grade in being; and therefore in them "genus"
and "difference" are not derived from different things, but from one and the
same. Nevertheless, this differs in our mode of conception; for, inasmuch as our intellect
considers it as indeterminate, it derives the idea of their "genus"; and
inasmuch as it considers it determinately, it derives the idea of their
"difference."
Reply to Objection 2
This reason is given in the book on the Fount of Life, and it would be
cogent, supposing that the receptive mode of the intellect and of matter were the same.
But this is clearly false. For matter receives the form, that thereby it may be
constituted in some species, either of air, or of fire, or of something else. But the
intellect does not receive the form in the same way; otherwise the opinion of Empedocles
(De Anima i, 5, text 26) would be true, to the effect that we know earth by earth, and
fire by fire. But the intelligible form is in the intellect according to the very nature
of a form; for as such is it so known by the intellect. Hence such a way of receiving is
not that of matter, but of an immaterial substance.
Reply to Objection 3
Although there is no composition of matter and form in an angel, yet there
is act and potentiality. And this can be made evident if we consider the nature of
material things which contain a twofold composition. The first is that of form and matter,
whereby the nature is constituted. Such a composite nature is not its own existence but
existence is its act. Hence the nature itself is related to its own existence as
potentiality to act. Therefore if there be no matter, and supposing that the form itself
subsists without matter, there nevertheless still remains the relation of the form to its
very existence, as of potentiality to act. And such a kind of composition is understood to
be in the angels; and this is what some say, that an angel is composed of, "whereby
he is," and "what is," or "existence," and "what is,"
as Boethius says. For "what is," is the form itself subsisting; and the
existence itself is whereby the substance is; as the running is whereby the runner runs.
But in God "existence" and "what is" are not different as was
explained above (Q3, ARTICLE 4). Hence God alone is pure act.
Reply to Objection 4
Every creature is simply finite, inasmuch as its existence is not
absolutely subsisting, but is limited to some nature to which it belongs. But there is
nothing against a creature being considered relatively infinite. Material creatures are
infinite on the part of matter, but finite in their form, which is limited by the matter
which receives it. But immaterial created substances are finite in their being; whereas
they are infinite in the sense that their forms are not received in anything else; as if
we were to say, for example, that whiteness existing separate is infinite as regards the
nature of whiteness, forasmuch as it is not contracted to any one subject; while its
"being" is finite as determined to some one special nature.
Reply to Objection 4
Whence it is said (De Causis, prop. 16) that "intelligence is finite from
above," as receiving its being from above itself, and is "infinite from
below," as not received in any matter.

ARTICLE 3
Whether the angels exist in any great number?
Objection 1
It would seem that the angels are not in great numbers. For number is a species
of quantity, and follows the division of a continuous body. But this cannot be in the
angels, since they are incorporeal, as was shown above (ARTICLE 1). Therefore the angels
cannot exist in any great number.
Objection 2
Further, the more a thing approaches to unity, so much the less is it
multiplied, as is evident in numbers. But among other created natures the angelic nature
approaches nearest to God. Therefore since God is supremely one, it seems that there is
the least possible number in the angelic nature.
Objection 3
Further, the proper effect of the separate substances seems to be the movements
of the heavenly bodies. But the movements of the heavenly bodies fall within some small
determined number, which we can apprehend. Therefore the angels are not in greater number
than the movements of the heavenly bodies.
Objection 4
Dionysius says (Div. Nom. iv) that "all intelligible and intellectual
substances subsist because of the rays of the divine goodness." But a ray is only
multiplied according to the different things that receive it. Now it cannot be said that
their matter is receptive of an intelligible ray, since intellectual substances are
immaterial, as was shown above (ARTICLE 2). Therefore it seems that the multiplication of
intellectual substances can only be according to the requirements of the first
bodies---that is, of the heavenly ones, so that in some way the shedding form of the
aforesaid rays may be terminated in them; and hence the same conclusion is to be drawn as
before.
On the contrary
On the contrary, It is said (Dan. 7:10): "Thousands of thousands ministered to
Him, and ten thousands times a hundred thousand stood before Him."
Body
I answer that, There have been various opinions with regard to the number of the
separate substances. Plato contended that the separate substances are the species of
sensible things; as if we were to maintain that human nature is a separate substance of
itself: and according to this view it would have to be maintained that the number of the
separate substances is the number of the species of sensible things. Aristotle, however,
rejects this view (Metaph. i, text 31) because matter is of the very nature of the species
of sensible things. Consequently the separate substances cannot be the exemplar species of
these sensible things; but have their own fixed natures, which are higher than the natures
of sensible things. Nevertheless Aristotle held (Metaph. xi, text 43) that those more
perfect natures bear relation to these sensible things, as that of mover and end; and
therefore he strove to find out the number of the separate substances according to the
number of the first movements.
But since this appears to militate against the teachings of Sacred Scripture, Rabbi
Moses the Jew, wishing to bring both into harmony, held that the angels, in so far as they
are styled immaterial substances, are multiplied according to the number of heavenly
movements or bodies, as Aristotle held (Metaph. xi, text 43); while he contended that in
the Scriptures even men bearing a divine message are styled angels; and again, even the
powers of natural things, which manifest God's almighty power. It is, however, quite
foreign to the custom of the Scriptures for the powers of irrational things to be
designated as angels.
Hence it must be said that the angels, even inasmuch as they are immaterial substances,
exist in exceeding great number, far beyond all material multitude. This is what Dionysius
says (Coel. Hier. xiv): "There are many blessed armies of the heavenly intelligences,
surpassing the weak and limited reckoning of our material numbers." The reason
whereof is this, because, since it is the perfection of the universe that God chiefly
intends in the creation of things, the more perfect some things are, in so much greater an
excess are they created by God. Now, as in bodies such excess is observed in regard to
their magnitude, so in things incorporeal is it observed in regard to their multitude. We
see, in fact, that incorruptible bodies, exceed corruptible bodies almost incomparably in
magnitude; for the entire sphere of things active and passive is something very small in
comparison with the heavenly bodies. Hence it is reasonable to conclude that the
immaterial substances as it were incomparably exceed material substances as to multitude.
Reply to Objection 1
In the angels number is not that of discrete quantity, brought about by
division of what is continuous, but that which is caused by distinction of forms;
according as multitude is reckoned among the transcendentals, as was said above (Q30,
ARTICLE 3; Q11).
Reply to Objection 2
From the angelic nature being the nighest unto God, it must needs have
least of multitude in its composition, but not so as to be found in few subjects.
Reply to Objection 3
This is Aristotle's argument (Metaph. xii, text 44), and it would conclude
necessarily if the separate substances were made for corporeal substances. For thus the
immaterial substances would exist to no purpose, unless some movement from them were to
appear in corporeal things. But it is not true that the immaterial substances exist on
account of the corporeal, because the end is nobler than the means to the end. Hence
Aristotle says (Metaph. xii, text 44) that this is not a necessary argument, but a
probable one. He was forced to make use of this argument, since only through sensible
things can we come to know intelligible ones.
Reply to Objection 4
This argument comes from the opinion of such as hold that matter is the
cause of the distinction of things; but this was refuted above (Q47, ARTICLE 1).
Accordingly, the multiplication of the angels is not to be taken according to matter, nor
according to bodies, but according to the divine wisdom devising the various orders of
immaterial substances.

ARTICLE 4
Whether the angels differ in species?
Objection 1
It would seem that the angels do not differ in species. For since the
"difference" is nobler than the 'genus,' all things which agree in what is
noblest in them, agree likewise in their ultimate constitutive difference; and so they are
the same according to species. But all angels agree in what is noblest in them---that is
to say, in intellectuality. Therefore all the angels are of one species.
Objection 2
Further, more and less do not change a species. But the angels seem to differ
only from one another according to more and less---namely, as one is simpler than another,
and of keener intellect. Therefore the angels do not differ specifically.
Objection 3
Further, soul and angel are contra-distinguished mutually from each other. But
all souls are of the one species. So therefore are the angels.
Objection 4
Further, the more perfect a thing is in nature, the more ought it to be
multiplied. But this would not be so if there were but one individual under one species.
Therefore there are many angels of one species.
On the contrary
On the contrary, In things of one species there is no such thing as "first"
and "second" prius et posterius, as the Philosopher says (Metaph. iii, text 2).
But in the angels even of the one order there are first, middle, and last, as Dionysius
says (Hier. Ang. x). Therefore the angels are not of the same species.
Body
I answer that, Some have said that all spiritual substances, even souls, are of the one
species. Others, again, that all the angels are of the one species, but not souls; while
others allege that all the angels of one hierarchy, or even of one order, are of the one
species.
But this is impossible. For such things as agree in species but differ in number, agree
in form, but are distinguished materially. If, therefore, the angels be not composed of
matter and form, as was said above (ARTICLE 2), it follows that it is impossible for two
angels to be of one species; just as it would be impossible for there to be several
whitenesses apart, or several humanities, since whitenesses are not several, except in so
far as they are in several substances. And if the angels had matter, not even then could
there be several angels of one species. For it would be necessary for matter to be the
principle of distinction of one from the other, not, indeed, according to the division of
quantity, since they are incorporeal, but according to the diversity of their powers; and
such diversity of matter causes diversity not merely of species, but of genus.
Reply to Objection 1
"Difference" is nobler than "genus," as the determined
is more noble than the undetermined, and the proper than the common, but not as one nature
is nobler than another; otherwise it would be necessary that all irrational animals be of
the same species; or that there should be in them some form which is higher than the
sensible soul. Therefore irrational animals differ in species according to the various
determined degrees of sensitive nature; and in like manner all the angels differ in
species according to the diverse degrees of intellectual nature.
Reply to Objection 2
More and less change the species, not according as they are caused by the
intensity or remissness of one form, but according as they are caused by forms of diverse
degrees; for instance, if we say that fire is more perfect than air: and in this way the
angels are diversified according to more or less.
Reply to Objection 3
The good of the species preponderates over the good of the individual.
Hence it is much better for the species to be multiplied in the angels than for
individuals to be multiplied in the one species.
Reply to Objection 4
Numerical multiplication, since it can be drawn out infinitely, is not
intended by the agent, but only specific multiplication, as was said above (Q47, ARTICLE
3). Hence the perfection of the angelic nature calls for the multiplying of species, but
not for the multiplying of individuals in one species.

ARTICLE 5
Whether the angels are incorruptible?
Objection 1
It would seem that the angels are not incorruptible; for Damascene, speaking of
the angel, says (De Fide Orth. ii, 3) that he is "an intellectual substance,
partaking of immortality by favor, and not by nature."
Objection 2
Further, Plato says in the Timaeus: "O gods of gods, whose maker and father
am I: You are indeed my works, dissoluble by nature, yet indissoluble because I so will
it." But gods such as these can only be understood to be the angels. Therefore the
angels are corruptible by their nature
Objection 3
Further, according to Gregory (Moral. xvi), "all things would tend towards
nothing, unless the hand of the Almighty preserved them." But what can be brought to
nothing is corruptible. Therefore, since the angels were made by God, it would appear that
they are corruptible of their own nature.
On the contrary
On the contrary, Dionysius says (Div. Nom. iv) that the intellectual substances
"have unfailing life, being free from all corruption, death, matter, and
generation."
Body
I answer that, It must necessarily be maintained that the angels are incorruptible of
their own nature. The reason for this is, that nothing is corrupted except by its form
being separated from the matter. Hence, since an angel is a subsisting form, as is clear
from what was said above (ARTICLE 2), it is impossible for its substance to be
corruptible. For what belongs to anything considered in itself can never be separated from
it; but what belongs to a thing, considered in relation to something else, can be
separated, when that something else is taken away, in view of which it belonged to it.
Roundness can never be taken from the circle, because it belongs to it of itself; but a
bronze circle can lose roundness, if the bronze be deprived of its circular shape. Now to
be belongs to a form considered in itself; for everything is an actual being according to
its form: whereas matter is an actual being by the form. Consequently a subject composed
of matter and form ceases to be actually when the form is separated from the matter. But
if the form subsists in its own being, as happens in the angels, as was said above
(ARTICLE 2), it cannot lose its being. Therefore, the angel's immateriality is the cause
why it is incorruptible by its own nature.
A token of this incorruptibility can be gathered from its intellectual operation; for
since everything acts according as it is actual, the operation of a thing indicates its
mode of being. Now the species and nature of the operation is understood from the object.
But an intelligible object, being above time, is everlasting. Hence every intellectual
substance is incorruptible of its own nature.
Reply to Objection 1
Damascene is dealing with perfect immortality, which includes complete
immutability; since "every change is a kind of death," as Augustine says (Contra
Maxim. iii). The angels obtain perfect immutability only by favor, as will appear later
(Q62).
Reply to Objection 2
By the expression 'gods' Plato understands the heavenly bodies, which he
supposed to be made up of elements, and therefore dissoluble of their own nature; yet they
are for ever preserved in existence by the Divine will.
Reply to Objection 3
As was observed above (Q44, ARTICLE 1) there is a kind of necessary thing
which has a cause of its necessity. Hence it is not repugnant to a necessary or
incorruptible being to depend for its existence on another as its cause. Therefore, when
it is said that all things, even the angels, would lapse into nothing, unless preserved by
God, it is not to be gathered therefrom that there is any principle of corruption in the
angels; but that the nature of the angels is dependent upon God as its cause. For a thing
is said to be corruptible not merely because God can reduce it to non-existence, by
withdrawing His act of preservation; but also because it has some principle of corruption
within itself, or some contrariety, or at least the potentiality of matter.