QUESTION 58: OF THE MODE OF ANGELIC KNOWLEDGE
After the foregoing we have now to treat of the mode of the angelic
knowledge, concerning which there are seven points of inquiry:
(1) Whether the angel's intellect be sometimes in potentiality, and
sometimes in act?
(2) Whether the angel can understand many things at the same time?
(3) Whether the angel's knowledge is discursive?
(4) Whether he understands by composing and dividing?
(5) Whether there can be error in the angel's intellect?
(6) Whether his knowledge can be styled as morning and evening?
(7) Whether the morning and evening knowledge are the same, or do they
Article 1: Whether the angel's intellect is sometimes in potentiality, sometimes in act?
Objection 1: It would seem that the angel's intellect is sometimes in
potentiality and sometimes in act. For movement is the act of what is in
potentiality, as stated in Phys. iii, 6. But the angels' minds are moved
by understanding, as Dionysius says (Div. Nom. iv). Therefore the angelic
minds are sometimes in potentiality.
Objection 2: Further, since desire is of a thing not possessed but possible to
have, whoever desires to know anything is in potentiality thereto. But it
is said (1 Pt. 1:12): "On Whom the angels desire to look." Therefore the
angel's intellect is sometimes in potentiality.
Objection 3: Further, in the book De Causis it is stated that "an intelligence
understands according to the mode of its substance." But the angel's
intelligence has some admixture of potentiality. Therefore it sometimes
On the contrary, Augustine says (Gen. ad lit. ii): "Since the angels
were created, in the eternity of the Word, they enjoy holy and devout
contemplation." Now a contemplating intellect is not in potentiality, but
in act. Therefore the intellect of an angel is not in potentiality.
I answer that, As the Philosopher states (De Anima iii, text. 8; Phys.
viii, 32), the intellect is in potentiality in two ways; first, "as
before learning or discovering," that is, before it has the habit of
knowledge; secondly, as "when it possesses the habit of knowledge, but
does not actually consider." In the first way an angel's intellect is
never in potentiality with regard to the things to which his natural
knowledge extends. For, as the higher, namely, the heavenly, bodies have
no potentiality to existence, which is not fully actuated, in the same
way the heavenly intellects, the angels, have no intelligible
potentiality which is not fully completed by connatural intelligible
species. But with regard to things divinely revealed to them, there is
nothing to hinder them from being in potentiality: because even the
heavenly bodies are at times in potentiality to being enlightened by the
In the second way an angel's intellect can be in potentiality with
regard to things learnt by natural knowledge; for he is not always
actually considering everything that he knows by natural knowledge. But
as to the knowledge of the Word, and of the things he beholds in the
Word, he is never in this way in potentiality; because he is always
actually beholding the Word, and the things he sees in the Word. For the
bliss of the angels consists in such vision; and beatitude does not
consist in habit, but in act, as the Philosopher says (Ethic. i, 8).
Reply to Objection 1: Movement is taken there not as the act of something
imperfect, that is, of something existing in potentiality, but as the act
of something perfect, that is, of one actually existing. In this way
understanding and feeling are termed movements, as stated in De Anima
iii, text. 28.
Reply to Objection 2: Such desire on the part of the angels does not exclude the
object desired, but weariness thereof. Or they are said to desire the
vision of God with regard to fresh revelations, which they receive from
God to fit them for the tasks which they have to perform.
Reply to Objection 3: In the angel's substance there is no potentiality divested
of act. In the same way, the angel's intellect is never so in
potentiality as to be without act.
Article 2: Whether an angel can understand many things at the same time?
Objection 1: It would seem that an angel cannot understand many things at the
same time. For the Philosopher says (Topic. ii, 4) that "it may happen
that we know many things, but understand only one."
Objection 2: Further, nothing is understood unless the intellect be informed
by an intelligible species; just at the body is formed by shape. But one
body cannot be formed into many shapes. Therefore neither can one
intellect simultaneously understand various intelligible things.
Objection 3: Further, to understand is a kind of movement. But no movement
terminates in various terms. Therefore many things cannot be understood
On the contrary, Augustine says (Gen. ad lit. iv, 32): "The spiritual
faculty of the angelic mind comprehends most easily at the same time all
things that it wills."
I answer that, As unity of term is requisite for unity of movement, so
is unity of object required for unity of operation. Now it happens that
several things may be taken as several or as one; like the parts of a
continuous whole. For if each of the parts be considered severally they
are many: consequently neither by sense nor by intellect are they grasped
by one operation, nor all at once. In another way they are taken as
forming one in the whole; and so they are grasped both by sense and
intellect all at once and by one operation; as long as the entire
continuous whole is considered, as is stated in De Anima iii, text. 23.
In this way our intellect understands together both the subject and the
predicate, as forming parts of one proposition; and also two things
compared together, according as they agree in one point of comparison.
From this it is evident that many things, in so far as they are distinct,
cannot be understood at once; but in so far as they are comprised under
one intelligible concept, they can be understood together. Now everything
is actually intelligible according as its image is in the intellect. All
things, then, which can be known by one intelligible species, are known
as one intelligible object, and therefore are understood simultaneously.
But things known by various intelligible species, are apprehended as
different intelligible objects.
Consequently, by such knowledge as the angels have of things through the
Word, they know all things under one intelligible species, which is the
Divine essence. Therefore, as regards such knowledge, they know all
things at once: just as in heaven "our thoughts will not be fleeting,
going and returning from one thing to another, but we shall survey all
our knowledge at the same time by one glance," as Augustine says (De
Trin. xv, 16). But by that knowledge wherewith the angels know things by
innate species, they can at one time know all things which can be
comprised under one species; but not such as are under various species.
Reply to Objection 1: To understand many things as one, is, so to speak, to
understand one thing.
Reply to Objection 2: The intellect is informed by the intelligible species which
it has within it. So it can behold at the same time many intelligible
objects under one species; as one body can by one shape be likened to
To the third objection the answer is the same as the first.
Article 3: Whether an angel's knowledge is discursive?
Objection 1: It would seem that the knowledge of an angel is discursive. For
the discursive movement of the mind comes from one thing being known
through another. But the angels know one thing through another; for they
know creatures through the Word. Therefore the intellect of an angel
knows by discursive method.
Objection 2: Further, whatever a lower power can do, the higher can do. But
the human intellect can syllogize, and know causes in effects; all of
which is the discursive method. Therefore the intellect of the angel,
which is higher in the order of nature, can with greater reason do this.
Objection 3: Further, Isidore (De sum. bono i, 10) says that "demons learn
more things by experience." But experimental knowledge is discursive:
for, "one experience comes of many remembrances, and one universal from
many experiences," as Aristotle observes (Poster. ii; Metaph. vii).
Therefore an angel's knowledge is discursive.
On the contrary, Dionysius says (Div. Nom. vii) that the "angels do not
acquire Divine knowledge from separate discourses, nor are they led to
something particular from something common."
I answer that, As has often been stated (Article ; Question , Article ), the angels
hold that grade among spiritual substances which the heavenly bodies hold
among corporeal substances: for Dionysius calls them "heavenly minds"
(Article ; Question , Article ). Now, the difference between heavenly and earthly
bodies is this, that earthly bodies obtain their last perfection by
chance and movement: while the heavenly bodies have their last perfection
at once from their very nature. So, likewise, the lower, namely, the
human, intellects obtain their perfection in the knowledge of truth by a
kind of movement and discursive intellectual operation; that is to say,
as they advance from one known thing to another. But, if from the
knowledge of a known principle they were straightway to perceive as known
all its consequent conclusions, then there would be no discursive process
at all. Such is the condition of the angels, because in the truths which
they know naturally, they at once behold all things whatsoever that can
be known in them.
Therefore they are called "intellectual beings": because even with
ourselves the things which are instantly grasped by the mind are said to
be understood [intelligi]; hence "intellect" is defined as the habit of
first principles. But human souls which acquire knowledge of truth by the
discursive method are called "rational"; and this comes of the feebleness
of their intellectual light. For if they possessed the fulness of
intellectual light, like the angels, then in the first aspect of
principles they would at once comprehend their whole range, by perceiving
whatever could be reasoned out from them.
Reply to Objection 1: Discursion expresses movement of a kind. Now all movement
is from something before to something after. Hence discursive knowledge
comes about according as from something previously known one attains to
the knowledge of what is afterwards known, and which was previously
unknown. But if in the thing perceived something else be seen at the same
time, as an object and its image are seen simultaneously in a mirror, it
is not discursive knowledge. And in this way the angels know things in
Reply to Objection 2: The angels can syllogize, in the sense of knowing a
syllogism; and they see effects in causes, and causes in effects: yet
they do not acquire knowledge of an unknown truth in this way, by
syllogizing from causes to effect, or from effect to cause.
Reply to Objection 3: Experience is affirmed of angels and demons simply by way
of similitude, forasmuch as they know sensible things which are present,
yet without any discursion withal.
Article 4: Whether the angels understand by composing and dividing?
Objection 1: It would seem that the angels understand by composing and
dividing. For, where there is multiplicity of things understood, there is
composition of the same, as is said in De Anima iii, text. 21. But there
is a multitude of things understood in the angelic mind; because angels
apprehend different things by various species, and not all at one time.
Therefore there is composition and division in the angel's mind.
Objection 2: Further, negation is far more remote from affirmation than any
two opposite natures are; because the first of distinctions is that of
affirmation and negation. But the angel knows certain distant natures not
by one, but by diverse species, as is evident from what was said (Article ).
Therefore he must know affirmation and negation by diverse species. And
so it seems that he understands by composing and dividing.
Objection 3: Further, speech is a sign of the intellect. But in speaking to
men, angels use affirmative and negative expressions, which are signs of
composition and of division in the intellect; as is manifest from many
passages of Sacred Scripture. Therefore it seems that the angel
understands by composing and dividing.
On the contrary, Dionysius says (Div. Nom. vii) that "the intellectual
power of the angel shines forth with the clear simplicity of divine
concepts." But a simple intelligence is without composition and division.
Therefore the angel understands without composition or division.
I answer that, As in the intellect, when reasoning, the conclusion is
compared with the principle, so in the intellect composing and dividing,
the predicate is compared with the subject. For if our intellect were to
see at once the truth of the conclusion in the principle, it would never
understand by discursion and reasoning. In like manner, if the intellect
in apprehending the quiddity of the subject were at once to have
knowledge of all that can be attributed to, or removed from, the subject,
it would never understand by composing and dividing, but only by
understanding the essence. Thus it is evident that for the self-same
reason our intellect understands by discursion, and by composing and
dividing, namely, that in the first apprehension of anything newly
apprehended it does not at once grasp all that is virtually contained in
it. And this comes from the weakness of the intellectual light within us,
as has been said (Article ). Hence, since the intellectual light is perfect
in the angel, for he is a pure and most clear mirror, as Dionysius says
(Div. Nom. iv), it follows that as the angel does not understand by
reasoning, so neither does he by composing and dividing.
Nevertheless, he understands the composition and the division of
enunciations, just as he apprehends the reasoning of syllogisms: for he
understands simply, such things as are composite, things movable
immovably, and material things immaterially.
Reply to Objection 1: Not every multitude of things understood causes
composition, but a multitude of such things understood that one of them
is attributed to, or denied of, another. When an angel apprehends the
nature of anything, he at the same time understands whatever can be
either attributed to it, or denied of it. Hence, in apprehending a
nature, he by one simple perception grasps all that we can learn by
composing and dividing.
Reply to Objection 2: The various natures of things differ less as to their mode
of existing than do affirmation and negation. Yet, as to the way in which
they are known, affirmation and negation have something more in common;
because directly the truth of an affirmation is known, the falsehood of
the opposite negation is known also.
Reply to Objection 3: The fact that angels use affirmative and negative forms of
speech, shows that they know both composition and division: yet not that
they know by composing and dividing, but by knowing simply the nature of
Article 5: Whether there can be falsehood in the intellect of an angel?
Objection 1: It would seem that there can be falsehood in the angel's
intellect. For perversity appertains to falsehood. But, as Dionysius says
(Div. Nom. iv), there is "a perverted fancy" in the demons. Therefore it
seems that there can be falsehood in the intellect of the angels.
Objection 2: Further, nescience is the cause of estimating falsely. But, as
Dionysius says (Eccl. Hier. vi), there can be nescience in the angels.
Therefore it seems there can be falsehood in them.
Objection 3: Further, everything which falls short of the truth of wisdom, and
which has a depraved reason, has falsehood or error in its intellect. But
Dionysius (Div. Nom. vii) affirms this of the demons. Therefore it seems
that there can be error in the minds of the angels.
On the contrary, The Philosopher says (De Anima iii, text. 41) that "the
intelligence is always true." Augustine likewise says (Questions. 83, qu. 32)
that "nothing but what is true can be the object of intelligence"
Therefore there can be neither deception nor falsehood in the angel's
I answer that, The truth of this question depends partly upon what has
gone before. For it has been said (Article ) that an angel understands not by
composing and dividing, but by understanding what a thing is. Now the
intellect is always true as regards what a thing is, just as the sense
regarding its proper object, as is said in De Anima iii, text. 26. But by
accident, deception and falsehood creep in, when we understand the
essence of a thing by some kind of composition, and this happens either
when we take the definition of one thing for another, or when the parts
of a definition do not hang together, as if we were to accept as the
definition of some creature, "a four-footed flying beast," for there is
no such animal. And this comes about in things composite, the definition
of which is drawn from diverse elements, one of which is as matter to the
other. But there is no room for error in understanding simple quiddities,
as is stated in Metaph. ix, text. 22; for either they are not grasped at
all, and so we know nothing respecting them; or else they are known
precisely as they exist.
So therefore, no falsehood, error, or deception can exist of itself in
the mind of any angel; yet it does so happen accidentally; but very
differently from the way it befalls us. For we sometimes get at the
quiddity of a thing by a composing and dividing process, as when, by
division and demonstration, we seek out the truth of a definition. Such
is not the method of the angels; but through the (knowledge of the)
essence of a thing they know everything that can be said regarding it.
Now it is quite evident that the quiddity of a thing can be a source of
knowledge with regard to everything belonging to such thing, or excluded
from it; but not of what may be dependent on God's supernatural
ordinance. Consequently, owing to their upright will, from their knowing
the nature of every creature, the good angels form no judgments as to the
nature of the qualities therein, save under the Divine ordinance; hence
there can be no error or falsehood in them. But since the minds of demons
are utterly perverted from the Divine wisdom, they at times form their
opinions of things simply according to the natural conditions of the
same. Nor are they ever deceived as to the natural properties of
anything; but they can be misled with regard to supernatural matters; for
example, on seeing a dead man, they may suppose that he will not rise
again, or, on beholding Christ, they may judge Him not to be God.
From all this the answers to the objections of both sides of the
question are evident. For the perversity of the demons comes of their not
being subject to the Divine wisdom; while nescience is in the angels as
regards things knowable, not naturally but supernaturally. It is,
furthermore, evident that their understanding of what a thing is, is
always true, save accidentally, according as it is, in an undue manner,
referred to some composition or division.
Article 6: Whether there is a "morning" and an "evening" knowledge in the angels?
Objection 1: It would seem that there is neither an evening nor a morning
knowledge in the angels; because evening and morning have an admixture of
darkness. But there is no darkness in the knowledge of an angel; since
there is no error nor falsehood. Therefore the angelic knowledge ought
not to be termed morning and evening knowledge.
Objection 2: Further, between evening and morning the night intervenes; while
noonday falls between morning and evening. Consequently, if there be a
morning and an evening knowledge in the angels, for the same reason it
appears that there ought to be a noonday and a night knowledge.
Objection 3: Further, knowledge is diversified according to the difference of
the objects known: hence the Philosopher says (De Anima iii, text. 38),
"The sciences are divided just as things are." But there is a threefold
existence of things: to wit, in the Word; in their own natures; and in
the angelic knowledge, as Augustine observes (Gen. ad lit. ii, 8). If,
therefore, a morning and an evening knowledge be admitted in the angels,
because of the existence of things in the Word, and in their own nature,
then there ought to be admitted a third class of knowledge, on account
of the existence of things in the angelic mind.
On the contrary, Augustine (Gen. ad lit. iv, 22,31; De Civ. Dei xii,
7,20) divides the knowledge of the angels into morning and evening
I answer that, The expression "morning" and "evening" knowledge was
devised by Augustine; who interprets the six days wherein God made all
things, not as ordinary days measured by the solar circuit, since the sun
was only made on the fourth day, but as one day, namely, the day of
angelic knowledge as directed to six classes of things. As in the
ordinary day, morning is the beginning, and evening the close of day, so,
their knowledge of the primordial being of things is called morning
knowledge; and this is according as things exist in the Word. But their
knowledge of the very being of the thing created, as it stands in its own
nature, is termed evening knowledge; because the being of things flows
from the Word, as from a kind of primordial principle; and this flow is
terminated in the being which they have in themselves.
Reply to Objection 1: Evening and morning knowledge in the angelic knowledge are
not taken as compared to an admixture of darkness, but as compared to
beginning and end. Or else it can be said, as Augustine puts it (Gen. ad
lit. iv, 23), that there is nothing to prevent us from calling something
light in comparison with one thing, and darkness with respect to another.
In the same way the life of the faithful and the just is called light in
comparison with the wicked, according to Eph. 5:8: "You were heretofore
darkness; but now, light in the Lord": yet this very life of the
faithful, when set in contrast to the life of glory, is termed darkness,
according to 2 Pt. 1:19: "You have the firm prophetic word, whereunto you
do well to attend, as to a light that shineth in a dark place." So the
angel's knowledge by which he knows things in their own nature, is day in
comparison with ignorance or error; yet it is dark in comparison with the
vision of the Word.
Reply to Objection 2: The morning and evening knowledge belong to the day, that
is, to the enlightened angels, who are quite apart from the darkness,
that is, from the evil spirits. The good angels, while knowing the
creature, do not adhere to it, for that would be to turn to darkness and
to night; but they refer this back to the praise of God, in Whom, as in
their principle, they know all things. Consequently after "evening" there
is no night, but "morning"; so that morning is the end of the preceding
day, and the beginning of the following, in so far as the angels refer to
God's praise their knowledge of the preceding work. Noonday is comprised
under the name of day, as the middle between the two extremes. Or else
the noon can be referred to their knowledge of God Himself, Who has
neither beginning nor end.
Reply to Objection 3: The angels themselves are also creatures. Accordingly the existence of things in the angelic knowledge is comprised under evening knowledge, as also the existence of things in their own nature.
Article 7: Whether the morning and evening knowledge are one?
Objection 1: It would seem that the morning and the evening knowledge are one.
For it is said (Gn. 1:5): "There was evening and morning, one day." But
by the expression "day" the knowledge of the angels is to be understood,
as Augustine says (Gen. ad lit. iv, 23). Therefore the morning and
evening knowledge of the angels are one and the same.
Objection 2: Further, it is impossible for one faculty to have two operations
at the same time. But the angels are always using their morning
knowledge; because they are always beholding God and things in God,
according to Mt. 18:10. Therefore, if the evening knowledge were
different from the morning, the angel could never exercise his evening
Objection 3: Further, the Apostle says (1 Cor. 13:10): "When that which is
perfect is come, then that which is in part shall be done away." But, if
the evening knowledge be different from the morning, it is compared to it
as the less perfect to the perfect. Therefore the evening knowledge
cannot exist together with the morning knowledge.
On the contrary, Augustine says (Gen. ad lit. iv, 24): "There is a vast
difference between knowing anything as it is in the Word of God, and as
it is in its own nature; so that the former belongs to the day, and the
latter to the evening."
I answer that, As was observed (Article ), the evening knowledge is that by
which the angels know things in their proper nature. This cannot be
understood as if they drew their knowledge from the proper nature of
things, so that the preposition "in" denotes the form of a principle;
because, as has been already stated (Question , Article ), the angels do not draw
their knowledge from things. It follows, then, that when we say "in their
proper nature" we refer to the aspect of the thing known in so far as it
is an object of knowledge; that is to say, that the evening knowledge is
in the angels in so far as they know the being of things which those
things have in their own nature.
Now they know this through a twofold medium, namely, by innate ideas, or
by the forms of things existing in the Word. For by beholding the Word,
they know not merely the being of things as existing in the Word, but the
being as possessed by the things themselves; as God by contemplating
Himself sees that being which things have in their own nature. It,
therefore, it be called evening knowledge, in so far as when the angels
behold the Word, they know the being which things have in their proper
nature, then the morning and the evening knowledge are essentially one
and the same, and only differ as to the things known. If it be called
evening knowledge, in so far as through innate ideas they know the being
which things have in their own natures, then the morning and the evening
knowledge differ. Thus Augustine seems to understand it when he assigns
one as inferior to the other.
Reply to Objection 1: The six days, as Augustine understands them, are taken as
the six classes of things known by the angels; so that the day's unit is
taken according to the unit of the thing understood; which, nevertheless,
can be apprehended by various ways of knowing it.
Reply to Objection 2: There can be two operations of the same faculty at the one
time, one of which is referred to the other; as is evident when the will
at the same time wills the end and the means to the end; and the
intellect at the same instant perceives principles and conclusions
through those principles, when it has already acquired knowledge. As
Augustine says (Gen. ad lit. iv, 24), the evening knowledge is referred
to the morning knowledge in the angels; hence there is nothing to hinder
both from being at the same time in the angels.
Reply to Objection 3: On the coming of what is perfect, the opposite imperfect is
done away: just as faith, which is of the things that are not seen, is
made void when vision succeeds. But the imperfection of the evening
knowledge is not opposed to the perfection of the morning knowledge. For
that a thing be known in itself, is not opposite to its being known in
its cause. Nor, again, is there any inconsistency in knowing a thing
through two mediums, one of which is more perfect and the other less
perfect; just as we can have a demonstrative and a probable medium for
reaching the same conclusion. In like manner a thing can be known by the
angel through the uncreated Word, and through an innate idea.