Article Second. On Amphibology and Mental Restriction

639. Declarations. 1. Amphibology is the use of words which of themselves are equivocal and therefore apt for generating a diverse sense. Thus gallus signifies a man sprung from Gaul and a rooster.

If someone uses amphibology, for example, "I killed a gallus," or "We are Germans," it can happen that the words are brought forth according to one signification by the speaker and understood according to another by the hearer, who is thus indeed deceived, yet nevertheless could understand the words also in the signification in which they are brought forth by the speaker: for of themselves they have a double sense.

2. Mental restriction is defined: an act of the mind by which the words of the speaker, through something which is kept silent or retained in the mind, are narrowed to another sense than the natural and obvious one.

It is one thing to lie, another to conceal the truth. Although to lie or to say what is false can never be licit, nevertheless to conceal the truth is often licit, indeed sometimes even necessary. Now mental restriction frequently is the only means of concealing the truth: for often neither is it permitted to decline a response nor to repel the one questioning.

3. A twofold restriction is distinguished: purely mental restriction, if the sense of the speaker can be perceived in no way, as if, when asked whether he has seen Rome, he responds, "Certainly," adding in his mind, "in a picture"; and broadly mental restriction, if the sense of the speaker can in some way be understood from the circumstances.

In mental restriction the words of themselves indeed have only one sense, but in the circumstances of person, place, or time in which they are brought forth, they admit another sense besides the natural one. Thus one asked about a secret which he knows but must conceal, and responding, "I do not know," manifestly denies only communicable knowledge; in this sense Christ denied that he knew the day of judgment.¹

¹ Cf. Mark 13:32; likewise John 7:8.

640. Principles. 1. From a just cause it is permitted to use amphibology or equivocation and to confirm it by oath.

Words brought forth amphibologically contain in themselves and externally in relation to the hearer the sense intended by the speaker; therefore the speech is not against the mind and hence is not a lie. Thus Christ said that he was sleeping who had died.¹ That a just cause is required in order that an amphibological oath be licit is clear from the things to be said below.

2. Purely mental restriction is never licit, because it does not differ from a lie: for in this restriction the words of the speaker, both of themselves and from the circumstances externally, have only one sense, and that discordant from the mind of the speaker.

Wherefore after the propositions (26, 27) condemned by Innocent XI, there is no theologian who says that purely mental restriction is licit, even if before this several had not judged it illicit.²

3. From a just cause we can licitly use broadly mental restriction, unless the one questioning has the right of knowing the truth; indeed sometimes we must use it.

a. This restriction is not a lie: for the words of the speaker are equivocal not of themselves but from the circumstances. Therefore they are conformed to the mind of the speaker, since they truly contain the sense which the speaker has in mind, even if only obscurely or incompletely. Moreover, for the good of society it is required that there be a means of licitly concealing the truth and preserving a secret; but, St. Alphonsus concludes (n. 152), "if it were not permitted to use broadly mental restriction, there would exist no mode of licitly concealing a secret, which would be harmful to human commerce no less than a lie." Finally, one's neighbor is not directly and necessarily deceived, but his deception is only permitted: for if the words of the speaker with restriction are taken by the hearer according to a false sense, the hearer is in reality deceived; but since the words of the speaker can be understood according to a true sense, the deception must be imputed not to the speaker but to the hearer himself.

alpha. A manifest sign of this necessity is detected in those affirmations of many by which they assert that they had to lie either for preventing discord or blasphemies or other inconveniences. In circumstances of this kind there is a just cause of using mental restriction; and since the faithful rarely grasp the theory concerning mental restriction, they must simply be told that the responses which they bring forth in circumstances of this kind for avoiding grave inconveniences are not lies but licit responses.

beta. From the end of restriction it is clear that the speaker can not only deliberately conceal the full truth through restriction, but can also desire and intend that the hearer not perceive the full truth; but it is permitted only to allow his deception. Yet in order that mental restriction be licit, it is required that the sense retained in the mind be able to be known morally or prudently from the circumstances. Therefore it is not necessary that the speaker use a restriction which the hearer easily supplies; yet this is required, that the restriction be able to be understood prudently and reasonably from the circumstances.

b. From a just cause: for it is not permitted without reason to furnish another an occasion of deception. Moreover, if this were always and without any cause permitted, no one could any longer believe another, because in any saying whatsoever he could and would have to suspect ambiguity, which would turn to manifest detriment of human society.

A just cause of using mental restriction is a true utility which follows from the concealed truth, or a true inconvenience, whether one's own or another's, which would follow from the truth manifested. But it is never permitted to use mental restriction where the one questioning has the right of knowing the truth: for to this right there corresponds in the other an obligation of confessing the truth without ambiguity, as if children are asked by parents, or those to be promoted to some office, order, or marriage, by superiors concerning a defect or crime committed, because they can and must withdraw from the office which they seek if they do not wish to declare the crime.³

c. We must use broadly mental restriction when neither can the truth about which inquiry is made be manifested without sin, nor can the one questioning be dismissed without a response.

An example by which this may be clear, if we prescind from the secret of confession and of office, is presented by Lehmkuhl, Casus conscientiae I, n. 455 ss.

4. From a just cause it is licit to confirm broadly mental restriction by oath: for since words brought forth with broadly mental restriction are true, God is not invoked in testimony of falsity.

a. A just cause of swearing with mental restriction is a great good to be preserved or grave damage to be avoided. Yet because many do not grasp the theory of mental restriction and others calumniate it, it is rarely expedient that oaths with mental restriction be recommended, unless they are necessary.

b. There are those who affirm that an oath emitted with mental restriction is repugnant both to the essence and to the end of an oath, and is therefore illicit. But they are plainly mistaken. For the essence of an oath requires that that which is confirmed by oath be true; but speech with broadly mental restriction is true. The end for which an oath was instituted does not require that this end be in reality obtained in individual cases, but that it can be obtained; or it requires only this, that the one swearing not impede the attainment of the end by a positive action, but only permit its frustration from a grave cause. But this obtains in oaths of this kind.

Note. All understand that for human intercourse a means of concealing the truth is necessary in those circumstances in which a response cannot be declined. According to the opinion of Catholics, this means is broadly mental restriction; but according to the doctrine of Protestants, it is a lie, or false-speech, which they say is licit when it harms no one but profits the speaker or another. Although practically in most circumstances broadly mental restriction and false-speech return to the same thing as to the matter, nevertheless the doctrine of Catholics must absolutely be held, both because it says that every lie is illicit and therefore more easily forestalls abuses, and because mental restriction, as speech true in itself, can be confirmed by oath, which sometimes is necessary; but a lie, even if it is called licit, cannot be confirmed by oath.

¹ John 11:11.

² Cf. Viva, Damnatae theses, on the cited propositions.

³ Cf. proposition 28 condemned by Innocent XI.

641. Applications. The difficulty of this matter is not in the liceity of mental restriction, which all must concede who understand what is signified by it; but the difficulty is in discerning purely mental restriction from broadly mental. Concerning this matter it must be noted that he who questions, from the usage received among men, does not expect, or cannot expect, any response except one conforming to the circumstances; and therefore the one responding does not lie if he restricts the response to the circumstances of the one questioning and of the one responding, provided he observes the condition proposed above (n. 640, 3, beta).

This is confirmed by common usage, from which it is established that circumstances bring it about that the words of the speaker can and must be understood in another sense than the natural and obvious one. Indeed, there are innumerable cases of human life in which the words of the speaker or of the one questioning are not accepted according to the sense which they have of themselves, but which they have from determined circumstances. Thus, to prescind from ironic sayings, one asked by him who seeks his father through the house whether he has seen his father rightly responds, "No," understanding well from the circumstances that the matter is whether he has seen the father here and now.

a. To one asking those things which cannot be manifested, it is licitly answered, "I do not know," namely, so as to tell you, or by communicable knowledge. Therefore a confessor asked whether Titius confessed homicide can and must respond: "I do not know," because he does not know it by communicable knowledge. Yet if the words or circumstances of the questioner are of such a kind that the word "I do not know" signifies every ignorance, it is not permitted to use it, but one must tell the questioner that he questions in vain. But the confessor, if the questioner were to insist whether he did not know this by communicable knowledge, can still answer, "I do not know": for since the questioner ought to know that the confessor cannot speak about this matter, he cannot prudently expect any other response unless he wishes to bear a refusal.

b. In those circumstances in which there is present a grave reason for concealing the truth, the denial of the thing, "No," from the common judgment of men, does not signify that the thing is denied, but that manifestation of the thing neither ought nor can be made. Therefore a penitent asked by a confessor about a sin which he is not bound to confess can respond with restriction that he did not commit it, namely, in such a way that he is bound to confess it, unless the confessor justly asks in order to know the state of the penitent: for the penitent rightly supposes that the confessor does not wish to question indiscreetly, and therefore expects a response only to those things which he prudently asks. But a prudent confessor ought to suspect that the response can be taken in this way.

c. If public persons are asked about matters committed to their trust, such as secretaries, legates of princes, leaders of armies, magistrates, advocates, physicians, surgeons, midwives, and whoever have an office and reason for concealing the truth, they can use restriction, rightly supposing that the one questioning does not wish to provoke them to an illicit or imprudent thing.

d. To one asking whether I can lend him money, it is permitted to respond, "I do not have it," subunderstanding: which I can easily or securely lend. For it can prudently be supposed that the one asking does not wish to be troublesome by his petition and therefore seeks only that money which can be lent without difficulty.

e. Servants from the will of their master can deny that he is at home, although he is present, because such speech from received usage signifies that he is not at home insofar as he can be seen or visited. Yet attention must be given to the custom of places.

f. He who is asked by a tax collector whether he has anything about which a tax must be paid can of himself respond that he has nothing, namely about which he must pay or which he must declare; for since of himself he is not bound to pay or declare, the collector by the highest right cannot prudently expect any response except one corresponding to the obligation of the speaker. Yet tax collectors questioning thus generally intend to free travelers from troublesome inspection; wherefore the words of the one questioning, from the circumstances, rather contain this sense: whether they have anything about which they would have to pay if it were detected by the inspector. Therefore tax collectors, especially from clerics and priests, deservedly expect a response without restriction.

g. Some restrictions which are called broadly mental by authors most certainly must be referred to the purely mental, because the conditions explained above are not observed. Thus if an adulterous woman, asked by her husband whether she committed adultery, denies this while subunderstanding idolatry, because idolatry in Sacred Scripture is sometimes called adultery, she uses purely mental restriction. By these things it is not denied that an adulteress can employ restriction and deny the crime committed, namely that she is bound to manifest it to her husband; for on the one side the husband does not have the right of knowing the hidden crimes of his wife, and on the other side the wife cannot manifest the truth without very grave inconvenience. Therefore the husband ought prudently to judge that the response can be conformable to the circumstances, and therefore inadequate.