St. Thomas Aquinas:
Quaestiones disputatae de veritate, q. 14 ("On faith")
Article 2: What is faith?
In Hebrews 11:1 the Apostle says that faith is the substance of things
to be hoped for, the argument (argumentum) of things that are not
IT SEEMS THAT IT IS INCORRECT TO SAY THIS:
1. No quality is a substance. Faith is a quality, since it is a virtue,
i.e., a good quality of the mind, etc. Therefore, faith is not a substance.
2. Further, spiritual being is added to natural being and is its perfection;
hence, it must be similar to it. But in the natural being of a human being
the substance is said to be the very essence of the soul, which is a first
act, but not the power of the soul, which is the principle of a second
act. Therefore, in a spiritual being one should not say that the essence
itself is faith or any other virtue, since a virtue is a proximate principle
of an operation and hence perfects a power. Rather, one should say that
the essence is grace, from which (i) spiritual being derives as from a
first act and which (ii) perfects the very essence of the soul.
3. Someone will claim that faith is called a substance because it is
the first among the different virtues. -- Against this one should reply
that virtues are considered in three ways, viz., (i) as regards their habits,
(ii) as regards their objects, and (iii) as regards their powers.
But as regards their habits, faith is not prior to the others. For
the definition under discussion seems to be a definition of faith only
insofar as faith is formed, since it is only in this sense that
it is the foundation, as Augustine says; but all the gratuitous virtues
are infused simultaneously. Similarly, as regards their objects,
faith does not seem to be prior to the other virtues. For it is not the
case that faith tends toward the true itself, which seems to be its proper
object, more than charity tends toward the highest good or more than hope
tends toward what is most difficult thing or toward the God's supreme liberality.
Similarly, as regards their powers, faith does not seem to be prior
to the other virtues, since all the gratuitous virtues seem to be referred
back to desire. Therefore, faith is in no way prior to the other virtues,
and so faith should not be called the foundation or the substance of the
4. Further, things to be hoped for subsist in us more through charity
than through faith. Therefore, the definition under discussion seems to
belong to charity rather than to faith.
5. Further, hope is generated from faith, as is evident in the Gloss
on Matthew 1:2, since 'faith' is posited in the definition of hope. But
'hope' is posited in the definition of a thing to be hoped for. Therefore,
if 'a thing to be hoped for' is posited in the definition of faith, there
will be a circularity in the definitions--which is absurd, since in that
case there will be something that is prior to and better known than itself.
For it will be possible for the same thing to be posited in the definition
of itself when the definitions are substituted for the names [defined],
and it will also be possible for the definitions to be infinite.
6. Further, diverse habits have diverse objects. But a theological virtue
has the same thing for both its end and its object. Therefore, among the
theological virtues it is necessary that the diverse virtues have diverse
ends. But a thing to be hoped for is the proper end of hope. Therefore,
'a thing to be hoped for' should not be posited in the definition of faith
either as an object or as an end.
7. Further, faith is perfected more by charity than by hope; that is
why it is said to be formed by charity. Therefore, in the definition
of faith one ought to posit the object of charity, which is a good or a
thing to be loved, rather than the object of hope, which is a thing to
be hoped for.
8. Further, faith is related precisely to the articles themselves. But
the articles do not all pertain to things to be hoped for--just one or
two do, viz., the resurrection of the flesh and life everlasting. Therefore,
'a thing to be hoped for' should not be posited in the definition of faith.
9. Further, arguing is an act of reason. But faith pertains to things
that are beyond reason. Therefore, it should not be called an argument.
10. Further, in the soul there are two movements, viz., toward the
soul and from the soul. Now in a movement toward the soul
the principle is extrinsic, whereas in a movement from the
soul the principle is intrinsic. But it is impossible for the same
thing to be both an intrinsic principle and an extrinsic principle. Therefore,
it is impossible for the same movement to be both toward the soul
and from the soul. But cogitation is perfected in a movement toward
the soul, whereas desire is perfected in a movement from the soul. Therefore,
neither faith nor anything else can be both a principle of desire and a
principle of cogitation. Therefore, in the definition of faith it is incorrect
to posit both something that pertains to desire, viz., 'the substance
of things to be hoped for', and something that pertains to cogitation,
viz., 'the argument of things that are not apparent'.
11. Further, a single habit cannot belong to diverse powers. But the
affective power and the intellective power are diverse powers. Therefore,
since faith is a single habit, it cannot pertain both to cognition and
affection; and so the same conclusion follows as before.
12. Further, a single habit has a single act. Therefore, since two
acts are being posited in the definition of faith, viz., (i) to make
the things that are hoped for subsist in us, in accord with which act one
says 'the substance of things to be hoped for', and (ii) to convince the
mind, in accord with which one says 'the argument of things that are not
apparent', it seems that faith is not being correctly described.
13. Further, understanding is prior to desire. But the phrase 'the substance
of things to be hoped for' pertains to desire, whereas what is afterwards
joined to it, viz., 'the argument of things that are not apparent', pertains
to understanding. Therefore, the parts of the definition in question are
14. Further, what is called an argument is that which induces the mind
to assent to something. But the mind is induced to assent to given things
because those things are apparent to it. Therefore, there seems to be an
opposition in the phrase that it is added, when one says 'the argument
of things that are not apparent'.
15. Further, faith is a kind of cognition. But every cognition is about
something that is apparent to the one who is cognizing. For by means of
a cognition something is apparent both in the sentient part of the soul
and in the intellective part of the soul. Therefore, it is inappropriate
to say that faith is of things that are not apparent.
One should reply that, according to some people, the Apostle intended
by this definition to show not what faith is but rather what faith
However, it seems better to reply that this explanation of faith is
the most complete definition of it--not in the sense that it is rendered
in the form appropriate to a definition, but rather because it adequately
touches upon all the things that are required for a definition of faith.
For sometimes it is sufficient for even philosophers themselves to touch
upon the principles of [given] syllogisms and definitions, and once these
principles are had, it is not difficult to reduce them to forms that are
in keeping with the doctrine of the art [of logic].
Now there are three indications of this point.
I. The first is the fact that all the principles on which
the existence of faith depends are touched upon in the definition under
For since, as was said above, the condition of one who believes is
such that his intellect is determined to something by his will, whereas
the will does nothing except insofar as it is moved by its object, which
is a desirable good and an end, [it follows that] two principles are required
for the end. One [A] is the good that moves the will, and
the second [B] is that to which the intellect assents when
the will makes it [assent].
A. Now there are two ultimate goods of a human being which
move the will primarily as ultimate ends.
One of these goods is proportionate to human nature, since natural
powers are sufficient to obtain it. And this is the happiness that
philosophers have spoken about, be it (i) contemplative happiness,
which consists in the act of wisdom, or (ii) active happiness, which
consists primarily in the act of prudence and derivatively in the acts
of the other moral virtues.
The other good for a human being exceeds a proportion
to human nature, since natural powers are not sufficient to obtain it,
or even to cogitate about it or desire it; instead, this good is promised
to a human being by God's liberality alone--1 Corinthians 2:9: "Without
you, O God, eye has not seen the things which you have prepared for those
who await you"--and this good is eternal life. And it is by
this good that the will is inclined toward assenting to those things which
it holds on faith; thus it is said in John 6:40, "Whoever sees the
Son and believes in him has eternal life."
Now nothing can be ordered to an end unless some sort of proportion
to the end preexists in it, a proportion from which there arises in it
a desire for the end. And this happens insofar as a sort of inception of
the end comes to exist in it, since it desires nothing except to the extent
that it desires some likeness of that [inception]. And so it is that in
human nature itself there is a sort of inception of that good which is
proportionate to [human] nature. For in human nature there naturally
preexist (i) principles of demonstration, known per se, which are
seeds of wisdom, and (ii) certain principles of the natural law, which
are seeds of the moral virtues.
Hence, in order for a human being to be ordered toward the good of eternal
life, it is also necessary that a sort of inception of that good should
come to exist in the one who is promised eternal life. But eternal life
consists in the full cognition of God, as is evident from John 17:3: "This
is eternal life, that they should know you, the only true God." Hence,
it is necessary that some inception of this supernatural cognition should
come to exist in us. And this inception comes through faith, which on the
basis of an infused light holds fast to things that by nature exceed our
Now in wholes that have ordered parts it is customary for the first
part, in which there exists an inception of the whole, to be called the
substance of the whole, e.g., the foundation of a house and the
keel of a ship. This is why the Philosopher claims in Metaphysics II
that if being were a single whole, its first part would be substance. And
so it is that faith, insofar as it is a sort of inception within us of
the eternal life that we hope for because of God's promise, is called the
substance of things to be hoped for. And so here one touches upon
the relation of faith to the good that moves the will when it determines
B. Now the will, moved by the aforementioned good, proposes something
that is not apparent to the intellect as being worthy of its assent, and
it determines the intellect to that which is not apparent in such a way
that [the intellect] assents to it. Therefore, just as an intelligible
thing that is seen by the intellect determines the intellect and because
of this is said to convince the mind, so too something that is not apparent
to the intellect determines it and induces it necessarily to assent to
it by the very fact that it is accepted by the will. This is why another
reading has 'conviction' (convictio), since it convinces the intellect
in the way just explained. And so in saying 'the argument of things that
are not apparent' one touches upon the relation of faith to that which
the intellect assents to.
So, then, we have (i) the matter or object of faith from
the fact that he says 'about things that are not apparent', (ii) the act
of faith from the fact that he says 'the argument', and (iii) the ordering
of faith to its end from the fact that he says 'the substance of things
to be hoped for'. Now on the basis of the act one also grasps (i) the genus,
viz., habit, which is known through the act, as well as (ii) the subject
[of the habit], viz., the mind. And nothing further is required for
the definition of a virtue.
Hence, in accord with what has been said it is easy to formulate the
definition in an artful way. So we may say that faith is a habit of
the mind by which eternal life begins in us, a habit which makes the intellect
assent to things that are not apparent.
II. The second indication is that through the definition
in question faith is distinguished from all other things.
For by saying 'of things that are not apparent' one distinguishes faith
from knowledge (scientia) and understanding (intellectus).
Again, by saying 'the argument' one distinguishes faith from (i) opinion
(opinio) and doubt (dubitatio), in which the mind is not
convinced, i.e., not determined to some one thing, and also from (ii) all
habits which are not cognitive. Again, by saying 'the substance of things
to be hoped for' one distinguishes [faith in the proper sense] from (i)
faith as it is commonly understood (fides communiter accepta), in
accord with which we are said either to believe that which we strongly
opine or to believe in the testimony of some human being, and also from
(ii) prudence (prudentia) and the other cognitive habits, which
are not ordered toward the things to hoped for or which, if they are so
ordered, are not such that a proper inception of the things to be hoped
for comes to exist in us through them.
III. The third indication is the fact that none of those
who have wanted to define faith has been able to define it otherwise than
by positing this whole definition or some part of it in different terms.
For when Damascene says, viz., "Faith is the hypostasis of things
that are hoped for and the proof of things that are not seen," it
is manifestly obvious that this is the same thing that the Apostle says.
On the other hand, when Damascene goes on to add, "The unshakable
and unquestionable hope in the things that have been announced to us by
God and in the efficacy of our prayers," this is a sort of explication
of what the Apostle had said, viz., "the substance of things to be
hoped for." For the things to be hoped for are, first of all, the
rewards that have been promised to us by God and, secondly, any other things
we seek from God as necessary for [obtaining] those rewards, things with
respect to which a firm hope is had through faith. This hope cannot fail,
and this is why it is called unshakable; nor can it be justifiably be reprehended
as a vain hope, and this is why it is called unquestionable.
Now when Augustine says, "Faith is a virtue by which things that
are not seen are believed," and, again, when Damascene says, "Faith
is not an examined consent," and when Hugo of St. Victor says, "Faith
is a sort of certitude of the soul with respect to absent, a certitude
that is superior to opinion and inferior to knowledge," this is the
same thing that the Apostle means by "the argument of things that
are not apparent." For faith is said to be inferior to knowledge because,
unlike knowledge, it does not include vision, even though it does include
firm adherence; on the other hand, faith is said to be superior to opinion
because of the firmness of the assent. And so faith is said to be inferior
to knowledge to the extent that it is of things that are not apparent,
and superior to opinion to the extent that it is an argument. And from
what has been said it is evident [what one should say] about the other
Moreover, when Dionysius says, "Faith is the enduring foundation
of those who believe, putting them in the truth and putting the truth in
them," this is the same thing that the Apostle means by "the
substance of things to be hoped for." For the cognition of truth is
a thing to be hoped for, since beatitude is nothing other than a rejoicing
in the truth, as Augustine says in the Confessions.
AD 1. To the first objection one should reply that faith is called a
substance not because it is in the genus of substance, but because it bears
a certain similarity to a substance, viz., insofar as it is a first inception
of and, as it were, a sort of foundation for the whole spiritual life--in
just the way that a substance is the foundation of all beings.
AD 2. To the second objection one should reply that the Apostle means
to be comparing faith not to those things that are within us but
to those things that are outside us. Now even though in natural
being it is the essence of the soul that is the first thing and the substance
with respect to the powers and the habits and all the resulting things
which are in [the soul], one nonetheless finds a relation to external things
not in the essence but primarily in the power; and, similarly, one finds
a relation to external things not in grace [itself] but in virtue, and
primarily in faith. This is why he was not able to say that grace, rather
than faith, is the substance of things to be hoped for.
AD 3. To the third objection one should reply that faith is prior to
the other virtues (i) on the part of its object and (ii) on the
part of its power and (iii) on the part of its habit.
It is prior on the part of its object not because it tends toward
its object more than the other virtues do, but because its object naturally
moves [the soul] before the object of charity and the objects of the other
virtues do. This is evident from the fact that what is good never moves
the appetite except through the intellect, as is said in On the Soul
III. By contrast, in order for what is true to move the intellect,
it does not need any movement on the part of the appetite. And this is
why the act of faith is naturally prior to the act of charity; and
the same holds for the habit of faith, even though [the habit of
faith and the habit of charity] exist together when the faith is formed
faith. And for this same reason a cognitive power is naturally
prior to an affective power.
Now faith exists in a cognitive power. This is evident from the fact
that the proper object of faith is the true and not the good.
However, faith does in a certain sense have its completion in the will,
as will be explained below in articles 4 and 9.
AD 4. To the fourth objection one should reply that it is already evident
from what has been said that the first inception of the things to be hoped
for comes to exist in us not through charity but through faith. Nor, again,
is charity an argument. Thus, the description under discussion does not
in any way belong to charity.
AD 5. To the fifth objection one should reply that since the good that
inclines us toward faith exceeds reason, it does not have a name. And so
by a sort of circumlocution one substitutes 'things to be hoped for' for
[this good]. This frequently happens in definitions.
AD 6. To the sixth objection one should reply that even though every
power has an end, which is its good, nonetheless not every power, but only
the will, is related to the nature of an end or a good insofar as it
is good. And this is why the will moves all the other powers; for every
motion begins with the intending of the end. Therefore, even though the
true is the end of faith, still 'the true' does not express the nature
of an end; hence, it is not the true, but rather something pertaining to
desire, that should be posited as the end of faith.
AD 7. To the seventh objection one should reply that a thing to be loved
can be either present or absent, whereas only what is absent is a thing
to be hoped for. Romans 8:24: "For who hopes for what he sees?"
Hence, since faith is of absent things, its end is more properly expressed
by 'thing to be hoped for' than by 'thing to be loved'.
AD 8. To the eighth objection one should reply that an article [of the
faith] is, as it were, the matter of faith, whereas a thing to be
hoped for is posited not as the matter but as the end. Hence, the
argument does not follow.
AD 9. To the ninth objection one should reply that 'argument' (argumentum)
is said in many ways.
For (i) sometimes it signifies the very act of reason by which
one reasons discursively from principles to conclusions. And (ii) because
the whole force of an argument consists in the middle term, the
middle term is also sometimes called an argument. Further, (iii) it is
also the case that the introductions to books, which contain a sort
of foretaste of the work that follows, are called arguments. And (iv) because
something is made manifest through an argument, the principle of manifestation,
as well as the very light by which something is cognized, can be called
And faith can be called an argument in each of these four ways.
It can be called an argument in the first way to the extent that
reason assents to something because it is said by God. And so because of
the authority of the speaker an assent is effected in the one who believes,
since in dialectics it is also the case that some arguments are taken from
Now in the second sense faith is called the argument of things
that are not apparent either (i) to the extent that the faith of believers
is a middle term for proving that things that are not apparent exist, or
(ii) to the extent that the faith of our fathers is for us a middle term
that induces us to believe, or (iii) to the extent that faith with respect
to one article is a middle term for faith with respect to another article,
in the way that Christ's resurrection is a middle term with respect to
the general resurrection, as is evident from 1 Corinthians 16:12.
Faith is called an argument in the third sense to the extent
that faith is a sort of meager foretaste of the cognition that we will
have in the future.
And faith is called an argument in the fourth sense as regards
the light of faith itself, through which the things believed are cognized.
Now faith is said to be beyond reason not because faith does not
involve an act of reason but rather because the reason involved in faith
cannot lead one to see the things which pertain to faith.
AD 10. To the tenth objection one should reply that the act of faith
consists essentially in cognition, and therein lies its perfection
as regards its form and species. This is evident from its object, as was
explained in the body of this article. But it is in affection that
faith is perfected as regards its end, since it is because
of charity that faith is meritorious with respect to the end. The inception
of faith also lies in affection to the extent that the will determines
the intellect to assent to the things which pertain to faith. But that
act of will is neither an act of charity nor a species of charity, but
is instead a certain desire for the promised good. And so it is evident
that faith does not exist in two powers as in a subject.
AD 11. The reply to the eleventh objection is evident from this.
AD 12. To the twelfth objection one should reply that in saying 'the
substance of things to be hoped for' one touches upon not the act of
faith but only upon its relation to the end. One touches upon the
act of faith when one relates faith to its object by saying
'the argument of things that are not apparent'.
AD 13. To the thirteenth objection one should reply that that to which
the intellect assents moves the intellect not because of its own power
but because of the inclination of the will. Hence, the good which moves
the desire is like a first mover in the act of faith, whereas that to which
the intellect assents is like a moved mover. And this is why in the definition
of faith the relation of faith to the good of the desire is posited before
its relation to its proper object.
AD 14. To the fourteenth objection one should reply that faith convinces
or induces the mind not because of the evidentness of the matter but rather
because of the will's inclination, as was explained in the body of this
article. Hence, the argument does not follow.
AD 15. To the fifteenth objection one should reply that 'cognition'
can convey two things, viz., (i) vision and (ii) assent.
Insofar as it conveys vision, cognition is distinguished from
faith. This is why Gregory says that things that are seen have cognition
rather than faith. According to Augustine in On Seeing God, those
things are said to be seen which are present to the senses or to the intellect.
But things that are said to be present to the intellect do not exceed its
However, as far as the certitude of the assent is concerned,
faith is a cognition, a cognition by virtue of which it can be called a
knowledge and a vision, according to 1 Corinthians 13:12: "We see
now darkly through a mirror." And this is what Augustine says in On
Seeing God: "If it is not improper to say that we know that which
we believe most certainly, then from this it follows that we are rightly
said to see with the mind the things that are believed, even though they
are not present to our senses."
Alfred J. Freddoso
University of Notre Dame