QUESTION 110: OF THE VICES OPPOSED TO TRUTH, AND FIRST OF LYING
We must now consider the vices opposed to truth, and (1) lying: (2)
dissimulation or hypocrisy: (3) boasting and the opposite vice.
Concerning lying there are four points of inquiry:
(1) Whether lying, as containing falsehood, is always opposed to truth?
(2) Of the species of lying;
(3) Whether lying is always a sin?
(4) Whether it is always a mortal sin?
Article 1: Whether lying is always opposed to truth?
Objection 1: It seems that lying is not always opposed to truth. For opposites
are incompatible with one another. But lying is compatible with truth,
since that speaks the truth, thinking it to be false, lies, according to
Augustine (Lib. De Mendac. iii). Therefore lying is not opposed to truth.
Objection 2: Further, the virtue of truth applies not only to words but also
to deeds, since according to the Philosopher (Ethic. iv, 7) by this
virtue one tells the truth both in one's speech and in one's life. But
lying applies only to words, for Augustine says (Contra Mend. xii) that
"a lie is a false signification by words." Accordingly, it seems that
lying is not directly opposed to the virtue of truth.
Objection 3: Further, Augustine says (Lib. De Mendac. iii) that the "liar's
sin is the desire to deceive." But this is not opposed to truth, but
rather to benevolence or justice. Therefore lying is not opposed to truth.
On the contrary, Augustine says (Contra Mend. x): "Let no one doubt that
it is a lie to tell a falsehood in order to deceive. Wherefore a false
statement uttered with intent to deceive is a manifest lie." But this is
opposed to truth. Therefore lying is opposed to truth.
I answer that, A moral act takes its species from two things, its
object, and its end: for the end is the object of the will, which is the
first mover in moral acts. And the power moved by the will has its own
object, which is the proximate object of the voluntary act, and stands in
relation to the will's act towards the end, as material to formal, as
stated above (FS, Question , Articles ,7).
Now it has been said above (Question , Article , ad 3) that the virtue of
truth---and consequently the opposite vices---regards a manifestation
made by certain signs: and this manifestation or statement is an act of
reason comparing sign with the thing signified; because every
representation consists in comparison, which is the proper act of the
reason. Wherefore though dumb animals manifest something, yet they do not
intend to manifest anything: but they do something by natural instinct,
and a manifestation is the result. But when this manifestation or
statement is a moral act, it must needs be voluntary, and dependent on
the intention of the will. Now the proper object of a manifestation or
statement is the true or the false. And the intention of a bad will may
bear on two things: one of which is that a falsehood may be told; while
the other is the proper effect of a false statement, namely, that someone
may be deceived.
Accordingly if these three things concur, namely, falsehood of what is
said, the will to tell a falsehood, and finally the intention to deceive,
then there is falsehood---materially, since what is said is false,
formally, on account of the will to tell an untruth, and effectively, on
account of the will to impart a falsehood.
However, the essential notion of a lie is taken from formal falsehood,
from the fact namely, that a person intends to say what is false;
wherefore also the word "mendacium" [lie] is derived from its being in
opposition to the "mind." Consequently if one says what is false,
thinking it to be true, it is false materially, but not formally, because
the falseness is beside the intention of the speaker so that it is not a
perfect lie, since what is beside the speaker's intention is accidental
for which reason it cannot be a specific difference. If, on the other
hand, one utters' falsehood formally, through having the will to deceive,
even if what one says be true, yet inasmuch as this is a voluntary and
moral act, it contains falseness essentially and truth accidentally, and
attains the specific nature of a lie.
That a person intends to cause another to have a false opinion, by
deceiving him, does not belong to the species of lying, but to perfection
thereof, even as in the physical order, a thing acquires its species if
it has its form, even though the form's effect be lacking; for instance a
heavy body which is held up aloft by force, lest it come down in
accordance with the exigency of its form. Therefore it is evident that
lying is directly an formally opposed to the virtue of truth.
Reply to Objection 1: We judge of a thing according to what is in it formally and
essentially rather than according to what is in it materially and
accidentally. Hence it is more in opposition to truth, considered as a
moral virtue, to tell the truth with the intention of telling a falsehood
than to tell a falsehood with the intention of telling the truth.
Reply to Objection 2: As Augustine says (De Doctr. Christ. ii), words hold the
chief place among other signs. And so when it is said that "a lie is a
false signification by words," the term "words" denotes every kind of
sign. Wherefore if a person intended to signify something false by means
of signs, he would not be excused from lying.
Reply to Objection 3: The desire to deceive belongs to the perfection of lying,
but not to its species, as neither does any effect belong to the species
of its cause.
Article 2: Whether lies are sufficiently divided into officious, jocose, and mischievous lies?
Objection 1: It seems that lies are not sufficiently divided into "officious,"
"jocose" and "mischievous" lies. For a division should be made according
to that which pertains to a thing by reason of its nature, as the
Philosopher states (Metaph. vii, text. 43; De Part. Animal i, 3). But
seemingly the intention of the effect resulting from a moral act is
something beside and accidental to the species of that act, so that an
indefinite number of effects can result from one act. Now this division
is made according to the intention of the effect: for a "jocose" lie is
told in order to make fun, an "officious" lie for some useful purpose,
and a "mischievous" lie in order to injure someone. Therefore lies are
unfittingly divided in this way.
Objection 2: Further, Augustine (Contra Mendac. xiv) gives eight kinds of
lies. The first is "in religious doctrine"; the second is "a lie that
profits no one and injures someone"; the third "profits one party so as
to injure another"; the fourth is "told out of mere lust of lying and
deceiving"; the fifth is "told out of the desire to please"; the sixth
"injures no one, and profits /someone in saving his money"; the seventh
"injures no one and profits someone in saving him from death"; the eighth
"injures no one, and profits someone in saving him from defilement of the
body." Therefore it seems that the first division of lies is insufficient.
Objection 3: Further, the Philosopher (Ethic. iv, 7) divides lying into
"boasting," which exceeds the truth in speech, and "irony," which falls
short of the truth by saying something less: and these two are not
contained under any one of the kinds mentioned above. Therefore it seems
that the aforesaid division of lies is inadequate.
On the contrary, A gloss on Ps. 5:7, "Thou wilt destroy all that speak a
lie," says "that there are three kinds of lies; for some are told for the
wellbeing and convenience of someone; and there is another kind of lie
that is told in fun; but the third kind of lie is told out of malice."
The first of these is called an officious lie, the second a jocose lie,
the third a mischievous lie. Therefore lies are divided into these three
I answer that, Lies may be divided in three ways. First, with respect to
their nature as lies: and this is the proper and essential division of
lying. In this way, according to the Philosopher (Ethic. iv, 7), lies are
of two kinds, namely, the lie which goes beyond the truth, and this
belongs to "boasting," and the lie which stops short of the truth, and
this belongs to "irony." This division is an essential division of lying
itself, because lying as such is opposed to truth, as stated in the
preceding Article: and truth is a kind of equality, to which more and
less are in essential opposition.
Secondly, lies may be divided with respect to their nature as sins, and
with regard to those things that aggravate or diminish the sin of lying,
on the part of the end intended. Now the sin of lying is aggravated, if
by lying a person intends to injure another, and this is called a
"mischievous" lie, while the sin of lying is diminished if it be directed
to some good---either of pleasure and then it is a "jocose" lie, or of
usefulness, and then we have the "officious" lie, whereby it is intended
to help another person, or to save him from being injured. In this way
lies are divided into the three kinds aforesaid.
Thirdly, lies are divided in a more general way, with respect to their
relation to some end, whether or not this increase or diminish their
gravity: and in this way the division comprises eight kinds, as stated in
the Second Objection. Here the first three kinds are contained under
"mischievous" lies, which are either against God, and then we have the
lie "in religious doctrine," or against man, and this either with the
sole intention of injuring him, and then it is the second kind of lie,
which "profits no one, and injures someone"; or with the intention of
injuring one and at the same time profiting another, and this is the
third kind of lie, "which profits one, and injures another." Of these the
first is the most grievous, because sins against God are always more
grievous, as stated above (FS, Question , Article ): and the second is more
grievous than the third, since the latter's gravity is diminished by the
intention of profiting another.
After these three, which aggravate the sin of lying, we have a fourth,
which has its own measure of gravity without addition or diminution; and
this is the lie which is told "out of mere lust of lying and deceiving."
This proceeds from a habit, wherefore the Philosopher says (Ethic. iv, 7)
that "the liar, when he lies from habit, delights in lying."
The four kinds that follow lessen the gravity of the sin of lying. For
the fifth kind is the jocose lie, which is told "with a desire to
please": and the remaining three are comprised under the officious lie,
wherein something useful to another person is intended. This usefulness
regards either external things, and then we have the sixth kind of lie,
which "profits someone in saving his money"; or his body, and this is the
seventh kind, which "saves a man from death"; or the morality of his
virtue, and this is the eighth kind, which "saves him from unlawful
defilement of his body."
Now it is evident that the greater the good intended, the more is the
sin of lying diminished in gravity. Wherefore a careful consideration of
the matter will show that these various kinds of lies are enumerated in
their order of gravity: since the useful good is better than the
pleasurable good, and life of the body than money, and virtue than the
life of the body.
This suffices for the Replies to the Objections.
Article 3: Whether every lie is a sin?
Objection 1: It seems that not every lie is a sin. For it is evident that the
evangelists did not sin in the writing of the Gospel. Yet they seem to
have told something false: since their accounts of the words of Christ
and of others often differ from one another: wherefore seemingly one of
them must have given an untrue account. Therefore not every lie is a sin.
Objection 2: Further, no one is rewarded by God for sin. But the midwives of
Egypt were rewarded by God for a lie, for it is stated that "God built
them houses" (Ex. 1:21). Therefore a lie is not a sin.
Objection 3: Further, the deeds of holy men are related in Sacred Writ that
they may be a model of human life. But we read of certain very holy men
that they lied. Thus (Gn. 12 and 20) we are told that Abraham said of his
wife that she was his sister. Jacob also lied when he said that he was
Esau, and yet he received a blessing (Gn. 27:27-29). Again, Judith is
commended (Judith 15:10,11) although she lied to Holofernes. Therefore
not every lie is a sin.
Objection 4: Further, one ought to choose the lesser evil in order to avoid
the greater: even so a physician cuts off a limb, lest the whole body
perish. Yet less harm is done by raising a false opinion in a person's
mind, than by someone slaying or being slain. Therefore a man may
lawfully lie, to save another from committing murder, or another from
Objection 5: Further, it is a lie not to fulfill what one has promised. Yet
one is not bound to keep all one's promises: for Isidore says (Synonym.
ii): "Break your faith when you have promised ill." Therefore not every
lie is a sin.
Objection 6: Further, apparently a lie is a sin because thereby we deceive our
neighbor: wherefore Augustine says (Lib. De Mend. xxi): "Whoever thinks
that there is any kind of lie that is not a sin deceives himself
shamefully, since he deems himself an honest man when he deceives
others." Yet not every lie is a cause of deception, since no one is
deceived by a jocose lie; seeing that lies of this kind are told, not
with the intention of being believed, but merely for the sake of giving
pleasure. Hence again we find hyperbolical expressions in Holy Writ.
Therefore not every lie is a sin.
On the contrary, It is written (Ecclus. 7:14): "Be not willing to make
any manner of lie."
I answer that, An action that is naturally evil in respect of its genus
can by no means be good and lawful, since in order for an action to be
good it must be right in every respect: because good results from a
complete cause, while evil results from any single defect, as Dionysius
asserts (Div. Nom. iv). Now a lie is evil in respect of its genus, since
it is an action bearing on undue matter. For as words are naturally signs
of intellectual acts, it is unnatural and undue for anyone to signify by
words something that is not in his mind. Hence the Philosopher says
(Ethic. iv, 7) that "lying is in itself evil and to be shunned, while
truthfulness is good and worthy of praise." Therefore every lie is a sin,
as also Augustine declares (Contra Mend. i).
Reply to Objection 1: It is unlawful to hold that any false assertion is
contained either in the Gospel or in any canonical Scripture, or that the
writers thereof have told untruths, because faith would be deprived of
its certitude which is based on the authority of Holy Writ. That the
words of certain people are variously reported in the Gospel and other
sacred writings does not constitute a lie. Hence Augustine says (De
Consens. Evang. ii): "He that has the wit to understand that in order to
know the truth it is necessary to get at the sense, will conclude that he
must not be the least troubled, no matter by what words that sense is
expressed." Hence it is evident, as he adds (De Consens. Evang. ii), that
"we must not judge that someone is lying, if several persons fail to
describe in the same way and in the same words a thing which they
remember to have seen or heard."
Reply to Objection 2: The midwives were rewarded, not for their lie, but for
their fear of God, and for their good-will, which latter led them to tell
a lie. Hence it is expressly stated (Ex. 2:21): "And because the midwives
feared God, He built them houses." But the subsequent lie was not
Reply to Objection 3: In Holy Writ, as Augustine observes (Lib. De Mend. v), the
deeds of certain persons are related as examples of perfect virtue: and
we must not believe that such persons were liars. If, however, any of
their statements appear to be untruthful, we must understand such
statements to have been figurative and prophetic. Hence Augustine says
(Lib. De Mend. v): "We must believe that whatever is related of those
who, in prophetical times, are mentioned as being worthy of credit, was
done and said by them prophetically." As to Abraham "when he said that
Sara was his sister, he wished to hide the truth, not to tell a lie, for
she is called his sister since she was the daughter of his father,"
Augustine says (Questions. Super. Gen. xxvi; Contra Mend. x; Contra Faust.
xxii). Wherefore Abraham himself said (Gn. 20:12): "She is truly my
sister, the daughter of my father, and not the daughter of my mother,"
being related to him on his father's side. Jacob's assertion that he was
Esau, Isaac's first-born, was spoken in a mystical sense, because, to
wit, the latter's birthright was due to him by right: and he made use of
this mode of speech being moved by the spirit of prophecy, in order to
signify a mystery, namely, that the younger people, i.e. the Gentiles,
should supplant the first-born, i.e. the Jews.
Some, however, are commended in the Scriptures, not on account of
perfect virtue, but for a certain virtuous disposition, seeing that it
was owing to some praiseworthy sentiment that they were moved to do
certain undue things. It is thus that Judith is praised, not for lying to
Holofernes, but for her desire to save the people, to which end she
exposed herself to danger. And yet one might also say that her words
contain truth in some mystical sense.
Reply to Objection 4: A lie is sinful not only because it injures one's neighbor,
but also on account of its inordinateness, as stated above in this
Article. Now it is not allowed to make use of anything inordinate in
order to ward off injury or defects from another: as neither is it lawful
to steal in order to give an alms, except perhaps in a case of necessity
when all things are common. Therefore it is not lawful to tell a lie in
order to deliver another from any danger whatever. Nevertheless it is
lawful to hide the truth prudently, by keeping it back, as Augustine says
(Contra Mend. x).
Reply to Objection 5: A man does not lie, so long as he has a mind to do what he
promises, because he does not speak contrary to what he has in mind: but
if he does not keep his promise, he seems to act without faith in
changing his mind. He may, however, be excused for two reasons. First, if
he has promised something evidently unlawful, because he sinned in
promise, and did well to change his mind. Secondly, if circumstances have
changed with regard to persons and the business in hand. For, as Seneca
states (De Benef. iv), for a man to be bound to keep a promise, it is
necessary for everything to remain unchanged: otherwise neither did he
lie in promising---since he promised what he had in his mind, due
circumstances being taken for granted---nor was he faithless in not
keeping his promise, because circumstances are no longer the same. Hence
the Apostle, though he did not go to Corinth, whither he had promised to
go (2 Cor. 1), did not lie, because obstacles had arisen which prevented
Reply to Objection 6: An action may be considered in two ways. First, in itself,
secondly, with regard to the agent. Accordingly a jocose lie, from the
very genus of the action, is of a nature to deceive; although in the
intention of the speaker it is not told to deceive, nor does it deceive
by the way it is told. Nor is there any similarity in the hyperbolical or
any kind of figurative expressions, with which we meet in Holy Writ:
because, as Augustine says (Lib. De Mend. v), "it is not a lie to do or
say a thing figuratively: because every statement must be referred to the
thing stated: and when a thing is done or said figuratively, it states
what those to whom it is tendered understand it to signify."
Article 4: Whether every lie is a mortal sin?
Objection 1: It seems that every lie is a mortal sin. For it is written (Ps. 6:7): "Thou wilt destroy all that speak a lie," and (Wis. 1:11): "The
mouth that belieth killeth the soul." Now mortal sin alone causes
destruction and death of the soul. Therefore every lie is a mortal sin.
Objection 2: Further, whatever is against a precept of the decalogue is a
mortal sin. Now lying is against this precept of the decalogue: "Thou
shalt not bear false witness." Therefore every lie is a mortal sin.
Objection 3: Further, Augustine says (De Doctr. Christ. i, 36): "Every liar
breaks his faith in lying, since forsooth he wishes the person to whom he
lies to have faith in him, and yet he does not keep faith with him, when
he lies to him: and whoever breaks his faith is guilty of iniquity." Now
no one is said to break his faith or "to be guilty of iniquity," for a
venial sin. Therefore no lie is a venial sin.
Objection 4: Further, the eternal reward is not lost save for a mortal sin.
Now, for a lie the eternal reward was lost, being exchanged for a
temporal meed. For Gregory says (Moral. xviii) that "we learn from the
reward of the midwives what the sin of lying deserves: since the reward
which they deserved for their kindness, and which they might have
received in eternal life, dwindled into a temporal meed on account of the
lie of which they were guilty." Therefore even an officious lie, such as
was that of the midwives, which seemingly is the least of lies, is a
Objection 5: Further, Augustine says (Lib. De Mend. xvii) that "it is a
precept of perfection, not only not to lie at all, but not even to wish
to lie." Now it is a mortal sin to act against a precept. Therefore every
lie of the perfect is a mortal sin: and consequently so also is a lie
told by anyone else, otherwise the perfect would be worse off than others.
On the contrary, Augustine says on Ps. 5:7, "Thou wilt destroy," etc.:
"There are two kinds of lie, that are not grievously sinful yet are not
devoid of sin, when we lie either in joking, or for the sake of our
neighbor's good." But every mortal sin is grievous. Therefore jocose and
officious lies are not mortal sins.
I answer that, A mortal sin is, properly speaking, one that is contrary
to charity whereby the soul lives in union with God, as stated above
(Question , Article ; Question , Article ). Now a lie may be contrary to charity in
three ways: first, in itself; secondly, in respect of the evil intended;
A lie may be in itself contrary to charity by reason of its false
signification. For if this be about divine things, it is contrary to the
charity of God, whose truth one hides or corrupts by such a lie; so that
a lie of this kind is opposed not only to the virtue of charity, but also
to the virtues of faith and religion: wherefore it is a most grievous and
a mortal sin. If, however, the false signification be about something the
knowledge of which affects a man's good, for instance if it pertain to
the perfection of science or to moral conduct, a lie of this description
inflicts an injury on one's neighbor, since it causes him to have a false
opinion, wherefore it is contrary to charity, as regards the love of our
neighbor, and consequently is a mortal sin. On the other hand, if the
false opinion engendered by the lie be about some matter the knowledge of
which is of no consequence, then the lie in question does no harm to
one's neighbor; for instance, if a person be deceived as to some
contingent particulars that do not concern him. Wherefore a lie of this
kind, considered in itself, is not a mortal sin.
As regards the end in view, a lie may be contrary to charity, through
being told with the purpose of injuring God, and this is always a mortal
sin, for it is opposed to religion; or in order to injure one's neighbor,
in his person, his possessions or his good name, and this also is a
mortal sin, since it is a mortal sin to injure one's neighbor, and one
sins mortally if one has merely the intention of committing a mortal sin.
But if the end intended be not contrary to charity, neither will the lie,
considered under this aspect, be a mortal sin, as in the case of a jocose
lie, where some little pleasure is intended, or in an officious lie,
where the good also of one's neighbor is intended. Accidentally a lie may
be contrary to charity by reason of scandal or any other injury resulting
therefrom: and thus again it will be a mortal sin, for instance if a man
were not deterred through scandal from lying publicly.
Reply to Objection 1: The passages quoted refer to the mischievous lie, as a
gloss explains the words of Ps. 5:7, "Thou wilt destroy all that speak a
Reply to Objection 2: Since all the precepts of the decalogue are directed to the
love of God and our neighbor, as stated above (Question , Article , ad 3; FS,
Question , Article , ad 1), a lie is contrary to a precept of the decalogue, in
so far as it is contrary to the love of God and our neighbor. Hence it is
expressly forbidden to bear false witness against our neighbor.
Reply to Objection 3: Even a venial sin can be called "iniquity" in a broad
sense, in so far as it is beside the equity of justice; wherefore it is
written (1 Jn. 3:4): "Every sin is iniquity [*Vulg.: 'And sin is
iniquity.']." It is in this sense that Augustine is speaking.
Reply to Objection 4: The lie of the midwives may be considered in two ways.
First as regards their feeling of kindliness towards the Jews, and their
reverence and fear of God, for which their virtuous disposition is
commended. For this an eternal reward is due. Wherefore Jerome (in his
exposition of Is. 65:21, 'And they shall build houses') explains that God
"built them spiritual houses." Secondly, it may be considered with regard
to the external act of lying. For thereby they could merit, not indeed
eternal reward, but perhaps some temporal meed, the deserving of which
was not inconsistent with the deformity of their lie, though this was
inconsistent with their meriting an eternal reward. It is in this sense
that we must understand the words of Gregory, and not that they merited
by that lie to lose the eternal reward as though they had already merited
it by their preceding kindliness, as the objection understands the words
Reply to Objection 5: Some say that for the perfect every lie is a mortal sin.
But this assertion is unreasonable. For no circumstance causes a sin to
be infinitely more grievous unless it transfers it to another species.
Now a circumstance of person does not transfer a sin to another species,
except perhaps by reason of something annexed to that person, for
instance if it be against his vow: and this cannot apply to an officious
or jocose lie. Wherefore an officious or a jocose lie is not a mortal sin
in perfect men, except perhaps accidentally on account of scandal. We may
take in this sense the saying of Augustine that "it is a precept of
perfection not only not to lie at all, but not even to wish to lie":
although Augustine says this not positively but dubiously, for he begins
by saying: "Unless perhaps it is a precept," etc. Nor does it matter that
they are placed in a position to safeguard the truth: because they are
bound to safeguard the truth by virtue of their office in judging or
teaching, and if they lie in these matters their lie will be a mortal
sin: but it does not follow that they sin mortally when they lie in other