Kinds of secrets

666. Preliminary notions. 1. A secret subjectively is the obligation of not manifesting some hidden matter; objectively it is the hidden matter itself and the matter to be kept hidden. A threefold secret is distinguished (besides the sacramental secret):

a. Natural, whose obligation arises without contract from the nature of the thing alone, namely because the matter which someone has known by chance cannot be manifested without another being reasonably unwilling.

b. Merely promised, whose obligation arises from a promise, if someone promises silence to another about a matter already known before.

This promise can be given in two diverse circumstances: for either one promises another secrecy concerning a matter which he already knew before, or he afterwards promises secrecy concerning a matter which he had received from another without secrecy.

c. Committed or strict, whose obligation likewise arises from a promise, if someone receives from another a matter previously unknown to himself under the condition and express or tacit promise of keeping secrecy.

a. Therefore one committed secret arises from a promise or explicit pact, and can be called a private committed secret; another arises from a promise or tacit pact, and can be called an official (committed) secret (Amtsgeheimnis). The observance of the former is demanded only by private good; the observance of the latter is demanded in some measure also by the common good.

b. By the obligation of official secrecy are held counselors, physicians, midwives, advocates, theologians, etc., to whom, by force of office or for the sake of seeking counsel or help, secrets are revealed. Some refer here also friends and relatives to whom, by right of friendship and kinship, secrets are manifested for the sake of help or consolation.

Note. A secret can be an invention of art or science; it can be some fact (for example, that an office is vacant); it can be a hidden crime. The same principles do not apply to every secret.

2. Anyone has a right to his own secret; hence of itself it is not lawful: a. to investigate a secret; b. to manifest a secret; c. to use secret knowledge.

a. It is not lawful to investigate a secret unjustly, because a secret is like another's property; therefore he who unjustly investigates a secret takes another's property away from its owner.

a. A secret which is an invention of art or science may not be investigated by unjust or dishonorable means (by listening secretly, opening letters, employing force or deceit), but it may be investigated by natural and honorable means (art, study): for the owner cannot reasonably be unwilling that each one strive to know these secrets by licit means. The same must be said of a secret which is some fact. b. A secret which is a hidden crime, either already committed or to be committed later, may be investigated when there is question of averting truly grave damage to oneself or to an innocent third person, which threatens from that very person whose secret it is.

b. It is not lawful to manifest a secret, because manifestation is against justice or at least against charity, unless there is question of a case in which use of the secret is lawful.

c. It is not lawful to use a secret, or secret knowledge unjustly acquired: for he who has inflicted an injury on another is bound to remove it, or at least not to continue it; but he who uses knowledge unjustly acquired to the damage of another continues the injury inflicted on another. It is lawful to use secret knowledge justly acquired for one's own or another's advantage, even if some damage to another follows from it: for when someone has justly acquired knowledge of a secret, whether there is question of a fact or of an invention of art or science, the right of secrecy ceases, because the secret itself ceases.¹ Nevertheless it is not lawful to use a committed secret for one's own or another's advantage against the will of the one committing it: for a secret is judged to be committed in such a way that he to whom it is committed must abstain not only from its manifestation but also from its use.²

¹ Cf. Lugo, l.c., disp. 14, n. 103; St. Alphonsus, l. 3, n. 969; Sporer-Bierbaum II, tract. 5, n. 674; Ballerini-Palmieri II, n. 1083.

² Cf. Elbel-Bierbaum I, pr. 4, n. 412 s.; Bucceroni, Casus consc., 2nd ed., n. 88, 5. Let the examples be: a. From another's opened letters someone knows that some office is vacant; using this knowledge he himself seeks and receives it earlier. b. By chance, hearing persons speaking in a loud voice, he knows an invention of art whose secret they were diligently guarding; he himself uses this knowledge for his own advantage. c. An advocate, knowing by reason of office the unstable state of someone's business, warns his brother, a creditor of that business, about this matter, so that he may provide for himself in time.

667. On natural secret. 1. A natural secret obliges either from justice or from charity, and therefore under grave obligation in a grave matter, namely where the neighbor, from its revelation, is affected either by grave sadness or by grave injury.

2. It is lawful to manifest a natural secret where it cannot be kept without grave inconvenience; this inconvenience indeed must be greater if the secret obliges from justice.

To reveal one or another secret of lesser moment does not exceed venial sin. In a (positive) doubt whether the secret is of slight or great moment, it cannot be revealed without grave sin, because the one revealing exposes himself to the danger not only of sinning gravely but also at the same time of causing grave damage; therefore the principle of probabilism cannot be applied in this case.

668. On a promised secret. 1. A promised secret as such obliges either from mere fidelity under light obligation, or from justice, and indeed in a grave matter even under grave obligation, according as the one promising intends to bind himself either from fidelity or from justice; ordinarily, however, it obliges only from fidelity.

a. The matter of a promised and committed secret is sometimes that which by its own nature must be kept hidden, and therefore imposes a double obligation, of natural secret and of promise.

b. It must be noted that a promise of keeping secrecy is sometimes made from mere propriety and civility; this promise indeed of itself induces no obligation.

2. A promised secret does not oblige: a. where it cannot be kept without grave inconvenience to oneself or another, unless someone expressly obligated himself otherwise; b. when the matter would have had to be manifested without the promise: for no one can obligate himself by a promise to that which is illicit.

Therefore he who is legitimately questioned by a judge or superior concerning some matter must manifest it, even if he had promised secrecy.

669. On a committed secret. A committed secret obliges from justice and therefore under grave obligation in grave matter, because this obligation arises from a promise burdensome on both sides. Moreover, the common good demands that the opportunity of seeking necessary counsel or help be available to all; but men would be deprived of this advantage unless, because of the grave obligation of this secret, they were certain concerning its observance.

a. The obligation of a committed secret is stricter and graver than that of a promised secret, and the obligation of an official secret is graver than the obligation of a privately committed secret. For a committed secret obliges from justice, but a promised secret ordinarily only from fidelity; an official committed secret, however, obliges even when otherwise the matter would have had to be manifested, because the common good demands that this secret be kept unharmed except in a few cases. Therefore a committed secret may not be opened even to a judge or superior legitimately questioning, and the one questioned must answer with restriction that he knows nothing, namely nothing which he can reveal.¹

b. Not all committed secrets are of the same strictness and obligation, but some urge more strictly than others; this must be attended to when there is question of the licit revelation of a committed secret. Thus the obligation of a secret which is committed entirely freely, without another cause, to a private man is less; the obligation of a secret which is committed to a private man for the sake of receiving counsel is greater; the obligation of a secret which is committed to men constituted in public office (physicians, advocates, etc.) is still greater; finally the obligation of a secret which is committed to counselors in public causes is the greatest (if we abstract from the sacrament).²

c. To reveal even a committed secret of greater moment to one or another prudent man under secrecy is a venial sin, provided no other grave damage follows from it, and the secret is not manifested to him from whom the one committing it especially wished it to be hidden: for a matter communicated to one person only can still be called secret; hence by this lesion of secrecy only a light injury is inflicted on another.

¹ By civil law it is for the most part prohibited that those who perform a public office, as pastors, physicians, etc., be questioned by magistrates or judges concerning those things which have been entrusted to them by reason of office. Yet in some places this is enjoined by civil law on all, even physicians who were present at childbirth, that they report the name of the father and mother to the magistrate. Where a law of this kind is in force, since it must be said to be just (so that children may know their parents), it must also be observed by physicians: for in this case the obligation of committed or official secrecy ceases for them.

² Cf. Lehmkuhl I, n. 1198.

670. A committed secret can licitly be revealed in the following four cases.

It is evident of itself that the obligation of secrecy ceases: a. if the consent of him who committed the secret can rightly and deservedly be presumed. If a subject (the example is Cardinal de Lugo's) manifests under secrecy to a superior the crime of some subject, it must be supposed that the informer indeed wishes to remain hidden, but it can also be supposed that he permits the superior to do concerning the delinquent what he judges opportune.¹ b. If the matter is already known or divulged from elsewhere; hence anyone can licitly speak of a committed secret with a man who has knowledge of it, even if this knowledge is not yet public. The same holds if he to whom the secret was committed received knowledge of the matter from elsewhere. Therefore the secret can be revealed:

1. If it is necessary for averting grave common damage to the Church or the republic: for the obligation of secrecy, which was introduced for the sake of the public good, ceases where the same public good demands the manifestation of the secret. But it is not lawful to reveal a secret because of light public damage, such as arises, for example, from the guilty man remaining unpunished.

If someone knows under secrecy another's purpose of harming the city, and the latter cannot otherwise be turned back from executing it, he can and must reveal the secret committed to him.

2. If it is necessary for averting grave damage unjustly to be inflicted on an innocent third person by him who committed the secret: for charity demands that we free the innocent from the injury of the harmful man even with some damage to the harmful man.

a. If Titius knows under secrecy another's purpose of killing Gaius, and the wicked man cannot be turned back from his purpose, Titius can and must manifest it as much as is necessary to avert the evil, for example by warning Gaius to take care for himself. Likewise a physician knowing that a bridegroom, who pretends himself healthy, is laboring under a contagious disease, could manifest the matter to the deceived bride, if the bridegroom, after warning, was unwilling to desist.

b. Note that the obligation of a committed secret does not cease in favor of the innocent unless the secret concerns an evil still to be inflicted by injury; for if the secret concerns an evil already committed, its obligation does not cease, even if by manifestation the damage of the innocent person could be averted. If, for example, someone knew from a committed secret that Titius is a homicide, he could not reveal the matter in order to free Sempronius, who is unjustly condemned to death in place of Titius. For just as Titius himself is not bound, with equal damage to himself, to manifest his own crime in order to free Sempronius from an evil of which he is not the cause except accidentally, so he to whom Titius committed the secret is not bound, indeed he cannot manifest the crime of Titius in order to free Sempronius. For Titius is reasonably unwilling concerning the revelation of a secret committed by himself, so long as he himself can licitly keep it.²

3. If it is necessary for averting grave damage to the one committing the secret himself: for the one committing cannot be reasonably unwilling concerning the manifestation of the secret.

If someone knows under secrecy that Gaius has resolved to enter marriage with a hidden impediment, and he cannot otherwise be impeded from entering marriage, he can and must denounce the impediment.

4. If it is necessary for averting grave damage to oneself, even if from this there would follow for the one committing the secret danger of death: for one accepting a secret is not judged to wish to bind himself with so great an inconvenience, unless he expressly promises that he will keep the secret even with the gravest inconvenience.

If someone knew under secrecy that homicide had been perpetrated by another, and he himself, to whom the secret was committed, being suspected of the homicide, was in danger of undergoing a grave penalty, he would licitly reveal the secret even with danger of death to the one committing it, supposing that there is not another means of averting the most grave penalty threatening.

¹ Lugo, disp. 14, n. 117.

² Cf. Laymann, l. 3, tr. 3, pr. 2, c. 5, n. 2.

A SECRET is some hidden matter concerning another which cannot be made known without causing him injury or displeasure. Besides the secret of the seal of confession, which is treated of elsewhere, divines distinguish three kinds of secret: the natural secret, the promised secret, and the secret which is communicated under an express or implied contract of secrecy.

When we come to the knowledge of something concerning another which cannot be made known without causing him injury or displeasure we are under the obligation of a natural secret not to make it known. This obligation arises from charity and justice, inasmuch as these virtues forbid us to do anything to the hurt or annoyance of our neighbour.

If we come to know something concerning our neighbour and then give a promise not to reveal it to others, we are bound by a promised secret. If the matter was of its nature secret, there would be the obligation of a natural secret independently of the promise. When the promise is given, a special obligation arising therefrom binds the party to secrecy. In case the matter was not of itself secret, the only obligation would be that arising from the promise. It depends to some extent on the intention of the promisor as to.what obligation he takes upon himself by his promise. He may intend to bind himself to keep his word by the virtue of fidelity, because it is the duty of an honest man to keep his promise. In this case, as fidelity only binds under pain of venial sin, there will only be this obligation to observe the promised secret. However, if the other party to whom secrecy was promised would suffer serious loss from the violation of the secret, or if the parties were bound by mutual promises, then justice would require the secret to be kept, and the violation of the obligation would of itself be gravely sinful. Apart even from these circumstances, the promisor may intend to give the other a right to secrecy in justice, and then he will be bound to observe it under pain of mortal sin, A secret which is confided to another under the condition that secrecy is to be observed constitutes the matter of an onerous contract and binds more strictly than either a natural or a promised secret. Such are secrets of office which officials of all sorts become aware of in the execution of the duties entrusted to them; professional secrets of doctors, lawyers, priests, and others, who are consulted as experts by people in doubt or difficulty; as well as all others which are entrusted to any person under the express or implied condition of secrecy.

The obligation to observe a natural secret will cease after the secret has become public property. The party whose secret it is may sometimes be reasonably presumed not to be unwilling that the matter should be communicated to another, as, for example, to somebody who can and who will be of assistance to him. If the public good requires that the secret should be made known in order to prevent public wrong, the obligation of secrecy will cease, for the public welfare is of greater importance than that of an individual. If serious harm threatens one’s self or some other innocent person, or the party whose secret is in question, and the harm can only be averted by making known the secret, this will be allowed in the case of natural or promised secrets. The right of defence from impending evil prevails over that of natural and promised secrets.

Even the obligation of the third class of secrets will cease when they cannot be observed without serious harm to the public weal. The natural law, however, which requires that people should be able to consult others in their difficulties in all security, demands that this class of secret should be observed in the case when even serious harm threatens some innocent person, unless he whose secret is in question is the cause of the impending evil. Thus, if I know as a professional secret who is the real culprit in the case of a crime wrongly imputed to an innocent person, I may disclose the real culprit if by some special means he caused the false accusation of the innocent person, otherwise I must keep the secret. ‘It is a disputed point among theologians whether I am bound to observe a secret at the peril of my life when it was entrusted to me under that express condition, some maintaining that no one can pledge his life in that way, others more probably holding the contrary. ’Whether or not I am bound at my own serious loss to keep a secret entrusted to me under the condition of secrecy depends to some extent on circumstances, Sometimes I cannot be supposed under the circumstances to have bound myself by so strict an obligation; but as a rule professional secrets will continue to be binding even when the observance of them entails serious loss.

We are bound to make known natural and promised secrets at the command of lawful superiors. The obligation of obedience to lawful authority prevails over that of secrecy due to individuals in those cases. And so a witness in a court of justice when lawfully questioned about what he knows under the obligation of natural or promised secrecy must give the evidence required. Similarly, secret impediments to marriage must be declared according to the precept contained in the proclamation of banns. Professional secrets, however, and, in general, secrets which belong to the third class, are privileged, and must not be declared, unless they have ceased to be binding for some such reason as those mentioned above. Secrecy in this case is demanded by the natural law, which gives the fullest possible security to those who consult others in their difficulties, and even the precept of one’s superior cannot avail against the natural law, as St Thomas teaches.¹

English law acknowledges the privilege of state secrets and of the professional secrets of lawyers, but in the case of doctors and clergymen it does not as yet go the full length of the doctrine laid down above.

¹ Summa, 2-2, q. 70, a. I, ad 2.

I. Notion. A secret is a hidden matter which cannot be manifested.

II. Division. A secret is distinguished into natural, promised, and entrusted. A natural secret is one which, from the nature of the matter, must be kept, namely because it cannot be revealed without damage or grief to one's neighbor; as if you know where someone has hidden his money, and you reveal this to a thief. A promised secret is one which someone, after receiving knowledge of it, has freely promised to keep; it can at the same time be natural. An entrusted secret is one which has been communicated to someone who did not know it, and who expressly or tacitly promised that he would keep it. By force of a tacit pact, for example, physicians, advocates, theologians, religious superiors, and others to whom recourse is had because of the office which they discharge, for the sake of seeking counsel, are bound to an entrusted secret (St. Alphonsus, III, 970). I said by force of a tacit pact; for by undertaking the office they undertake an obligation without which, if it had not been undertaken, subjects and clients would not approach them with sufficient security for the sake of seeking counsel or imploring help.

III. Obligation of keeping a secret. 1. A natural secret obliges from charity if the revelation merely creates sorrow; from justice if it creates damage for one's neighbor. Hence the said obligation is grave from its kind.

A proportionate cause excuses from the obligation, as was said concerning manifestation of a hidden crime or defect (n. 1070). Yet it is clear that a secret cannot be revealed if common damage would be imminent from the revelation (St. Alphonsus, III, 970).

2. A promised secret obliges from fidelity or from justice, according as was said concerning a promise in general (n. 864).

The obligation of a promised secret ceases or does not subsist: 1° by the consent, even presumed, of the promisee; 2° if from another source there was, or there arises, an obligation of revealing the secret, as if you are legitimately questioned by a judge or by a superior (St. Alphonsus, III, 970; IV, 268); 3° if it cannot be kept without such inconvenience that the one promising cannot be judged to have wished to bind himself with so great a burden. Moreover, these statements hold even if the promise was confirmed by oath.

Sometimes a promise is added to a natural secret; in that case the added promise is judged to be merely confirmatory of the obligation already existing, so that it stands or falls with the latter. Yet it is not repugnant that an obligation independent of the existing obligation be intended and assumed. Apply the same to an oath, if perhaps it is added to a natural secret.

Question. To what extent is he obliged who expressly promised that he would keep a secret of very great importance even with the loss of life? I said of very great importance, because otherwise the promise would certainly be prodigal and therefore invalid.

Response. Some say that he is not obliged, because from the precept of charity each person is bound to prefer his own life to another's good, however very grave. Others maintain the obligation, because every promise of an honorable object obliges. But the promise about which we are speaking regards an honorable object; since it is permitted "for an honorable end to omit the preservation of one's own life in order to save another's life... because this is not directly to bring death upon oneself, but not to protect life, which is permitted for a just cause: therefore very probably the doctors... say that in the proposed case you are sufficiently obliged to keep the secret even with danger of life, if you promised it" (St. Alphonsus, III, 971). Yet note that the words even with danger of life must more often be taken less strictly according to the mind of the one promising.

3. An entrusted secret obliges from justice, and therefore by an obligation grave from its kind (n. 978). Moreover, the said obligation is stricter by reason of the onerous contract intervening. With respect to the promise at least tacitly made by the adviser, there is added the fact that it is of the greatest interest to the common good that the secret entrusted to him bind most strictly, namely so that men may be able to seek counsel without fear of revelation. Yet it is sufficiently probable that it is not a grave sin to reveal an entrusted secret to one or another person who will certainly keep it and will not even reveal it to one or another person. Moreover, this is sufficiently probable because in that case the secret remains safe as to its substance. Except, however, if the secret is revealed to him from whom the one entrusting it wishes it to be hidden before all others; in that case it would be a grave sin (St. Alphonsus, III, 971). I said sufficiently probably, because a contract is involved, and it is doubtful whether that more benign interpretation is valid; with respect to a natural secret, the matter is certain.

The obligation of an entrusted secret ceases: 1° by the consent, even reasonably presumed, of the one entrusting the secret; 2° if, from the secret being kept, grave damage is imminent either to the common good, or to the one entrusting the secret himself, or - provided he accepted the secret without force or fraud - to the one accepting the secret. The first two are sufficiently clear; the latter is drawn from this, that "no one is presumed to have obliged himself to such a burden, unless this certainly appears from the circumstances" (St. Alphonsus, III, 971). The obligation of an entrusted secret does not cease from the questioning of a judge or superior; and "you can respond that you know nothing, namely nothing to be revealed" (St. Alphonsus, III, 970). Except if the obligation of the secret has already ceased from another heading (St. Thomas, II-II, q. 70, a. 1, ad 2; St. Alphonsus, III, 970, 971; IV, 49, 248, 268).

What if grave damage is imminent to a third party from an entrusted secret being kept?

Response 1. If the damage is neither created nor culpably permitted by the one entrusting the secret, it is not lawful to reveal the secret; suppose that an advocate knows that an innocent man will be condemned, but the guilty man will be freed. If, because of special circumstances, the guilty man can permit the damage of the innocent man, the advocate also is bound to keep the secret entrusted to him.

Response 2. Outside the aforesaid case, I distinguish between those who are not bound by force of office and those who are bound by force of office to keep the secret. Now:

1. One who is not bound by force of office to keep the secret can certainly reveal it: 1° if the damage to the third party is created by the one entrusting the secret himself; as if a syphilitic, who pretends that he is healthy, intends to marry a bride ignorant of the bridegroom's disease; 2° if the damage to the third party is not indeed created by the one entrusting the secret, but nevertheless is culpably permitted by him; as if the guilty man mentioned above would culpably permit the damage of the innocent man. The reason for both is that charity demands that the secret be disclosed in order to avert damage to one's neighbor, unless the common good stands in the way. But the common good does not require that one who is not bound by force of office to be silent should be obliged to be silent, if a grave cause for speaking, i.e. for revealing the secret, exists (St. Alphonsus, III, 971).

2. The same, with St. Alphonsus and others against many, seems to be admitted if there is question of those who are bound by force of office to keep a secret; as if a physician knows that the bridegroom is afflicted with a contagious disease, and nevertheless does not wish to abstain from marriage. For on the one hand the reason just given is valid; on the other hand, the common good in this case does not demand that secrets of this sort be kept even with grave damage to a third party. For it is more in the interest of the common good that provision be made for the innocent person than for the harmful one, i.e. for him who wishes to inflict unjust damage on an innocent person, or who does not wish himself, by manifestation of the secret, to avert the damage to be inflicted on the innocent person (St. Alphonsus, III, 971). Yet the physician, etc., would be excused if grave damage to himself, for example hatred of citizens, a penalty to be imposed, etc., would be imminent from the revelation.

Objection 1. The common good demands that each person be able, without fear of revelation, to entrust a secret to those who furnish counsel by reason of office.

Response. On account of the reason just given, I deny the assertion with respect to those about whom the discussion is here. Nor, for that reason, will others to whom these things cannot be applied reasonably seek counsel with fear.

Objection 2. One who knows an impediment of marriage under an entrusted secret is not bound to reveal it, although there is question of averting damage.

Response. I deny the assertion taken generally; namely, one is bound to reveal an impediment, however known under an entrusted secret, if it is supposed and known that the impediment is known to one of the persons about to marry and unknown to the other, and therefore that formal injustice will be committed by one of the persons about to marry. And a case of this kind is especially intended by us.

Note 1. To an entrusted secret also belongs what is called a quasi-sacramental secret, namely one which arises from the manifestation of conscience to a superior or spiritual director, for the sake of seeking counsel or obtaining spiritual direction. Before this secret can be revealed, or even merely used, to avert some damage, even common damage, generally the one seeking counsel should first be warned concerning his obligation of preventing that damage by spontaneous manifestation or use of the secret; if he refuses, it should be well weighed whether in the case the gravity of the damage in question is not to be postponed to the gravity of that common damage which arises from the fact that, at least apparently, faith is broken in this matter.¹

Note 2. In some kingdoms a promissory oath concerning keeping a secret must be made by physicians; this oath, as is clear, is not valid insofar as you suppose that in some respect it is opposed to the law of nature.

¹ Aertnys-Damen, Theologia Moralis, I, n. 1004.

IV. Investigation of a secret. 1. Per se it is illicit and unjust to seek out another's secret against his will, for example by questioning deceitfully, reading letters, spying on the things which someone purposely does secretly, or by extorting a secret by a certain force. The reason is that one acting thus deprives another of his own thing; since a secret or hidden matter is most proper to a man. Moreover, it is a grave or light sin according as there is question of a grave or light matter. Except, with respect to a grave matter, if someone fishes out another's secret with the intention of keeping it to himself; this is sufficiently probably only light (n. 1069).

2. It is lawful to seek out a secret if there is at least presumed permission of the owner, or a proportionate cause, of which sort is damage to be averted, whether common damage, or grave damage to oneself or one's own. The reason is that there is no injury if the other consents or is bound to consent to the investigation itself of the secret.

Corollary I. It is lawful to read another's letters (i.e. whether written by subjects or sent to subjects): 1° as was said, from consent, even presumed, either of the writer or of the recipient; 2° if from the secret of the letters common damage, or damage to oneself or a third party, is feared; 3° if the rule of a religious institute prescribes or permits this, namely for the common good. Besides, parents, guardians, and superiors of institutes generally can read the letters of subjects, namely lest some evil befall them. A husband, however, per se cannot inspect letters given to his wife, since she is not plainly a subject but a companion. Often there will be consent at least presumed. For the rest, what a religious superior can do should be drawn from the rule and from custom (St. Alphonsus, III, 969; V, 70).

Corollary II. It seems illicit to join and read fragments of letters that have been torn very small and thrown away, because the owner, by tearing the letters, sufficiently signifies that he does not wish them to be read. The contrary must be said if the owner tore them into larger parts and voluntarily threw them into a place accessible to all (St. Alphonsus, loc. cit.).

V. Use of a secret. 1. Use of a secret communicated as such, which takes place without revelation of the secret - suppose if someone uses knowledge of a secret to direct others in the way of perfection - is lawful if it is done without damage to him whose secret it was; for what does not harm you is, with the required suppositions in place, lawful for me. If it is done with damage, it is illicit, unless there is added the consent, at least presumed, of the one communicating the secret, or a proportionate cause for allowing the damage; for a secret is judged to have been communicated with the burden of not harming the one communicating the secret.

2. Use of a secret not communicated, but investigated by just industry - suppose an invention publicly displayed and attentively inspected by an expert - is lawful; since the one investigating by his own industry made the secret his own, and therefore he can use it; except if a monopoly of using it had already been granted to another by the State.

3. Use (whether revelation, or use without revelation) of a secret unjustly extorted, with damage to him whose secret it was, is lawful for averting damage to oneself or to others only when the matter has been brought to that state in which it would be lawful to seek out the secret; otherwise it is illicit, because it would be a continuation of the injustice (St. Alphonsus, III, 969).

Infidelity and Violation of a Secret.—It remains to speak of the vices of infidelity and violation of secret (see 2388 a). As to the former, since it has been discussed elsewhere (1877 sqq., 1888, 1889; see also the matter on Promissory Oaths), it will suffice here to ask the question: Is the breach of a promise freely given a sin?

(a) If observance of the promise is due from fidelity only, there is no legal fault, but there is moral fault, and hence the breach of the promise is a sin. The malice is essentially the same as that of untruthfulness (see 2395), for both the liar and the promise-breaker show themselves unreliable, the former because his words do not square with his mind and the latter because his deeds do not live up to his plighted word. Breach of promise, then, seems per se to be a venial sin, though there are often circumstances (such as damage done) that make it mortal.

(b) If observance of the promise is not due even from fidelity, on account of the presence of some defect, there is no moral obligation to keep the promise and no sin is committed by not keeping it. The defects referred to are such as make the promise lack force from the beginning (e.g., if it was immoral or extorted by force), or deprive it of the force it had (i.e., inability on the part of the promisor or loss of right on the part of the promisee). The promisor is unable to keep the promise, if the thing promised has become physically impossible (e.g., he no longer has the strength or the means to perform what he promised), or morally impossible (e.g., the thing promised has become unlawful, or a notable change has taken place which, could it have been foreseen, would have prevented the promise). The promisee loses his right if the sole or principal reason that dictated the promise has ceased, or if the promise has become useless to the promisee, or if the promisor has been released, or if the promisee forfeits his claim by his own perfidy towards the promisor (see 2256 sqq., 1889).

Definition of a Secret.—A secret is a matter (e.g., an invention, valuable information, concealed virtues, the fact that a crime has been committed) known privately by only one person or by so few that it is neither public property nor notorious. Moralists distinguish the following kinds of secrets:

(a) a natural secret, which is one that cannot be revealed without causing injury or annoyance to another, as when the revelation will harm a person in his reputation, honor, influence property. It is called natural for it arises from the very nature of the matter of the secret and not from any promise or contract.

(b) a promised secret, which is one that a person has promised, but only after he had already learned it, to guard inviolate. It makes no difference whether the promisor learned the secret from the promisee or from some other source;

(c) an entrusted or committed secret, which is one that a person promised (and before he learned it) to keep from others. The promise here is either implicit or explicit. An implicit promise of secrecy is one that is demanded by the confidential nature of communications between two parties (professional secret), as when physicians, lawyers, priests, parents, or friends are told of private matters on account of their position or relationship. An explicit promise is one that is given in express terms, as when A says to B: “I have a matter of great importance to tell you, but you must first promise that you will keep it secret”; and on B promising, A confides to him the secret.

Sinfulness of Violating a. Secret.—A secret is the property of its owner, and to it he has a strict right; for if it is a good secret (such as an original idea or discovery), it is the product of his labor or at least a possession which he has lawfully come by; if it is an evil secret (such as a crime of which he has been guilty), it may not be made known without infringing on his right of reputation. It is no more lawful to violate the right to a secret than to violate the right to property, and, as there are three kinds of injuries to property, so there are three kinds of injuries to a secret.

(a) Thus, the right of possession is injured by those who by fraud or force or other illegal means deprive another of his secret (e.g., by secretly intercepting private letters, by making a person drunk in order to learn a secret).

(b) The right of use is injured by those who on acquiring knowledge of a secret guide themselves or others by it to the detriment of the owner’s rights.

(c) The right of disposition is injured by those who reveal a secret which they were obliged not to reveal.

Prying Into Others’ Secrets.—To seek to discover the secrets of others is not lawful unless the following conditions are present:

(a) one must have a right to the knowledge. Hence, if there is question about a crime that has been committed or that is about to be committed, one has a right to investigate in order to prevent harm to public or private good; in war one may try to discover the plans of the enemy. But it is not lawful to pry into purely personal matters, to fish from others natural or confidential secrets which they are bound to keep, to steal from another the thoughts, plans, inventions, etc, which are his own;

(b) one must use only honest means to discover secrets to which one has a right (1504). Thus, it does not seem lawful generally to inebriate another in order to learn his secret, and it is certainly sinful to resort to lies or simulation or immorality.

Reading Another’s Letters or Papers.—When is it lawful to read the letters or other papers of another person?

(a) This is lawful when the writings are not intended to be secret to anyone, as when a circular is meant for public use, when greetings are written on a postcard which all may read, and when a letter is left open and thrown away or otherwise abandoned. But a sealed letter, or one left open in a private room, or one lost in a public place, is secret. If a letter or manuscript has been torn up by its owner and thrown away on the street or other public place, it does not seem lawful to piece the fragments together and read the writing, for, though the paper has been abandoned, the owner by destroying it has indicated his will to keep the contents secret.

(b) It is also lawful to read the writing of others that are not secret as regards oneself, as when one has received a just permission from the writer to peruse a letter written by him, or when one may presume such permission on account of friendship with the writer, or when rule or lawful custom gives the superior of an institution the right to inspect the correspondence of his subjects. Exception must be made for exempted matter for which there is no permission, such as letters containing conscience matters and letters directed to higher religious superiors (see Canon 611).

(c) It is also lawful to read the writings of others that are meant to be secret, if one has a right to know what is in them: for in such a case the owner would be unreasonable if he wished to exclude one from the knowledge. Thus, the public authority (e.g., in time of war) has the right to open and read letters and private papers, when this is necessary for the common good; parents and heads of boarding schools may examine the correspondence of their subjects, though parents should respect conscience matter and others should not read family secrets; private individuals have the natural right, as a measure of self-defense, to read another’s letter, when there is a prudent reason for thinking that it contains something gravely and unjustly harmful to themselves (such as conspiracy, a trap, calumny).

Lawfulness of Utilizing Knowledge of Secret.—One is said to use the knowledge obtained from a secret when one guides one’s conduct by the knowledge, doing or omitting what one would not otherwise do or omit. Is this use of a secret lawful?

(a) If there was a promise not to use the secret, such use is unlawful (see 2414). Breach of promise is then, in case of a merely promised secret, an act of infidelity at least, and in case of an entrusted secret an act of injustice. Thus, when one consults a professional person, there is a tacit understanding that the knowledge communicated will not be used against one’s interests or without one’s consent, and hence a lawyer would be unjust if, on learning in the course of work for a client that the latter’s business was not prosperous, he gave word of this to one of the client’s creditors.

(b) If there was no promise not to use the secret, the use of it is nevertheless unjust, if it infringes a strict right (e.g., to make money from a secret process on which another has a patent, to get knowledge of another’s information and plans through reading his letters and thereby to prevent him from securing a vacant position), or if it is equivalent to unjust revelation of a secret. The use is uneharitable if it harms another person without necessity (e.g., to take away one’s trade from a deserving merchant solely because one has learned that on one occasion he was accidentally intoxicated).

(c) If there was no promise to avoid use and no harm will be done by use, it is lawful to use a secret for a non-necessary good (e.g., to raise the price on one’s property when one accidentally learns through overhearing a secret conversation that the property is worth the higher price), and it is obligatory to use it for a necessary good (e.g., to assist a neighbor when one is told under secret that he is in dire need of one’s charitable help). Even though harm will result to another by use of the secret, use is not sinful if it infringes no right and could be sacrificed only at great inconvenience to oneself, as when one has discovered by one’s own industry some important truth in an art or science which another had previously discovered but had neglected to make his own by exclusive right, or when one learns under secret that another person is one’s enemy and has to be watched and avoided.

The Sin Committed by Stealing or Unduly Using the Secret of Another.—(a) From its nature (cases of mere fidelity excepted) the sin is mortal, as being a violation of commutative justice or of charity. Injury to property rights, whether in goods or in knowledge, is violation of a strict right (see 1890, 1894). The sin is aggravated by the greater import of the secret or by the greater damages or displeasure caused.

(b) From the imperfection of the act or the lightness of the matter the sin may become venial, as when one thoughtlessly reads another person’s letters, or opens correspondence without authority, feeling morally sure that there is nothing confidential in it, or makes use of an unimportant secret without permission.

The Obligation of Keeping a Secret.—(a) The natural secret obliges per se under grave sin; for violation of it offends charity and justice by saddening and harming a neighbor. The sin may become venial on account of lightness of matter, as when little sadness or harm is caused.

(b) The promised secret obliges ordinarily under light sin only; for as a rule the promisor intends to obligate himself in virtue of fidelity alone (1888), and the obligation of fidelity, as said above (see 2407), is not grave. But exceptionally the obligation may be grave, as when the promisor intended to bind himself in virtue of justice and under grave sin, or when the secret is natural as well as promised.

(c) The entrusted secret obliges per se under grave sin; for there is a duty of commutative and of legal justice to keep it, on account of the rights of contract and of the common good that are involved. The violator of an entrusted secret injures private good by disregard for contract, and he injures public good by weakening confidence in officials or professional persons to whom others must go for advice or assistance. Violation of a committed secret may be only a venial sin on account of the lightness of the matter. Thus, some think it is not a serious injustice to reveal a secret to one very discreet person, if the person whose secret is made known is not very much opposed to this and no other damage will result (see 2065).

Comparison of Secrets as Regards Binding Force.—(a) The promised secret obliges less than the natural or the entrusted, as was said in the previous paragraph. (b) The natural secret obliges less per se than the entrusted secret, for the safeguarding of the latter is agreed to in an onerous contract, while no engagement is made to keep the former. (c) Some entrusted secrets are more sacred than others. Thus, a secret confided from necessity is more binding than one confided without necessity; a secret one has sworn to keep is more obligatory than a secret one has given one’s word of honor to keep; a professional secret is more imperious than a private secret; a state secret is far more important than any secret of private individuals. The most inviolable of all secrets is that of the confessional, because its violation is always a sacrilege.

Cases Wherein It Is Not Necessary to Keep a Secret.—(a) If there has been no obligation from the time the secret was learned, it is not necessary to keep it. Thus, if a merely promised secret was accepted under compulsion and revelation will be advantageous and not harmful, it does not seem necessary to keep the secret.

(b) If the obligation of the secret has ceased, it is not necessary to be silent. Examples are cases in which secrecy was promised only for a certain space of time, or in which a matter formerly secret has become public, or in which the owner of the secret wishes it to be divulged, or in which he has not kept faith with the possessor of the secret, provided of course that in these cases no injury or unnecessary harm is done by making known the secret. Similarly, if the recipient of the secret cannot keep it without grave harm (e.g., death) to himself, he is not bound by it, unless charity (see 1165, 1236) or justice calls for the contrary. Commutative justice would demand silence (though many make exception for a most grave reason, regarding a promise to the contrary as prodigal) if there had been an express contract to guard the secret at all risks; legal justice would demand it, if the safety of the republic were involved.

Cases Wherein It Is Not Lawful to Keep a Secret.—(a) If a secret cannot be kept without greater harm to the common good, it may not be kept, for legal justice requires that private good be subordinated to public safety. The violation of secrets is a harm to the public good and a greater harm than ordinary evils against the community (such as the escape of a guilty person); but it is a less harm than serious evils against the people (such as menace to public health, sedition, or treason). The possessor of a natural or promised secret must make it known at the command of lawful authority, as in court; but the superior has no right to question about entrusted secrets of a necessary kind, and this is usually recognized by positive law in the protection extended to professional communications.

(b) If a secret cannot be kept without greater harm to the private good of the owner of the secret, distinction is made between a non-entrusted and an entrusted secret. In the former case the secret may not be kept, for charity bids one to help a neighbor escape a greater evil, and the owner of the secret would be unreasonable if he were opposed to its revelation (see 501 sqq.). In the latter case, some are of the opinion that the secret should be kept, if it is professional (since the public good then takes precedence over the private good of the owner of the secret), but this is denied by others. Example: Titus knows that Balbus is about to marry with a secret impediment that will nullify the marriage, but he cannot persuade Balbus to disclose this impediment to the pastor.

(c) If a secret cannot be kept without greater harm to the private good of a third party (i.e., one other than the owner of the secret), distinction is made between cases, according as injury is or is not done by the owner of the secret to the third party. If no injury is done the third party, the secret should be kept (e.g., if one knows in confidence that Sempronius has made an invention which will supersede an invention made by Claudius, one is not at liberty to make this known to the latter, for Sempronius has done no injury to Claudius). If, however, injury is done the third party by the owner of the secret when the secret is kept, one should not keep the secret; for charity requires that one help an innocent person to escape from harm, even if this has to be done at the expense of harm to the guilty cause of the harm. Examples: If one knows as a secret that A, B and C have conspired to murder D tomorrow night, and one cannot otherwise prevent the murder, one should if possible break the secret, at least by sending warning to D that his life is in danger tomorrow night. If a doctor knows that a man who is about to contract marriage is syphilitic and pretends that he is sound, and if the doctor cannot persuade this man to make the facts known to the intended wife, the doctor himself should give notice to the woman, according to some authorities, unless the laws of the country forbid such use of professional knowledge.

Lawfulness of Revealing a Secret Learned by Stealth or Force.—Is it lawful, in order to avert some great evil, to use or reveal against the interests or wishes of its owner a secret which one has learned by stealth (e.g., by spying, eavesdropping, wiretapping, unauthorized inspection of papers) or by force? Various answers are given to this question, but to us the following seems the best:

(a) if the stealth or force would not be unjust here and now, because the owner of the secret has a duty to disclose it (e.g., on account of the public good, on account of the extreme need of a private person), or the other party has a right to seek after it (e.g., because he cannot otherwise defend himself against the unjust vexation of the owner of the secret), the answer is in the affirmative; for in such a case there is only applied the principle of lawful occupation or of lawful self-defense (see 1920 sqq., 1819). But if the stealth or force is excessive in its manner or productive of unnecessary harm, it is sinful and induces the duty of restitution, nor is there any right to make such use or such revelation of a secret as is sinful in itself (e.g., on account of calumnies, scandals, disorders);

(b) if the stealth or force would be unjust here and now, the answer is in the negative; for in such a case there is real theft of a secret, a person’s most intimate possession, and a continuation of the original injury by the use of the stolen property against its owner, or at least an unlawful conversion of property. Hence, if there is no grave or proportionate reason for the use of the secret, or if other and simpler methods can be employed, the secret may not be used. Those who play the detective ostensibly for other reasons but really for purposes of blackmail or other personal advantage, are therefore in the same class as thieves and are bound to restitution; their sin is per se mortal, for secrets are usually esteemed more highly than money, and it would be seriously detrimental to the public weal if the practice of using secrets unlawfully obtained (e.g., by secretly taking down privileged communications or state secrets) were permissible.

What is a secret, and how manyfold is it? A secret in general is called whatever is hidden. As pertains to the present question, a secret is: some hidden thing revealed to someone, or known in any way, with the burden of silence. - A threefold secret is distinguished: natural, promised, committed. A natural secret exists if by chance you know something which you cannot reveal without the just sorrow or damage of another. It is promised if by a gratuitous promise you promise another that you will reveal to no one a thing which you already knew or of which you receive knowledge; or by an onerous promise of revealing the thing to no one, another manifests it to you under this condition. Finally it is committed when you reveal a matter to another for the sake of counsel or help, with this express or tacit condition, of revealing it to no one. L. 970.; St. Thomas, Quodl. 12, a. 21.

What of the obligation of the seal of Confession? - The seal of Confession is the religious obligation of preserving secrecy concerning those things which are known from sacramental Confession, namely of manifesting them to others neither directly nor indirectly, nor, outside confession, to the penitent himself. - There is a most strict obligation of preserving the seal of Confession inviolably.

This is clear 1. From natural law, and indeed under a threefold title, namely from charity, from justice, and from religion. 2. From positive divine law, at least implicit; for from the institution of Christ, Confession, imposed on all from necessity of precept and from necessity of means, must be secret: therefore by that very fact there has been imposed by Christ on confessors the obligation of preserving the seal. 3.

From ecclesiastical law, the Fourth Lateran Council, C. 21, Omnis utriusque sexus, etc. - The obligation of the seal of Confession always presses in every case, so that in no possible case is it lawful to reveal anything heard and received in Confession. The reason is manifestly clear; because if some exception could be given, men would always fear lest such a sin be that cause for licitly breaking the seal, and consequently the sacrament of penance would become odious. Moreover no cause of obtaining good or avoiding evil can compensate for that evil of hatred of the sacrament. - The obligation of the seal arises from every and only sacramental Confession, namely one made with the intention of accusing oneself and obtaining absolution. From every, because then the whole reason for the precept is present; and this holds even if absolution has not been conferred for whatever reason, since Confession is made in order to receive absolution at some time. From only, because only sacramental Confession induces the obligation of the seal, since any other manifestation has no relation with the sacrament of penance. - L. 634, 636; E. M.

418. I. Notion of a secret. A secret is a matter, not yet made public knowledge, which ought to be preserved hidden. - It can be threefold: (a) natural, which from the very nature of the matter ought to be guarded, because the matter cannot be manifested without damage to the neighbor; e.g., if you know where another's money is hidden which robbers intend to steal, by the natural law, without any promise, you are prohibited from manifesting this; (b) promised, when someone explicitly promises to keep silence concerning a hidden matter which he already knew beforehand; e.g., if someone, after hearing a secret, spontaneously or at the petition of a friend, says: I promise you to press the matter with deep silence; (c) committed, when the matter is not revealed to someone except under an express or tacit promise of preserving secrecy; express, if it is said: I shall not manifest this matter to you except under the condition that you be silent concerning it; tacit, when a hidden matter is committed to someone who from office, by force of the duty which he bears, or by special title of kinship or friendship, is bound to preserve the secret matter; thus physicians, advocates, priests, parents and friends and others, to whom a hidden matter is not manifested except because it is supposed that it is to be guarded faithfully. - When a sin is declared under the seal of confession, it is called sacramental.

419. II. On the obligation of a secret. First principle: Those who violate a natural or committed secret without cause commit a sin against justice, and indeed grave from its kind.

(A) As regards a natural secret, this is clear; for, from the definition given above, it cannot be violated without damage being inflicted upon the neighbor in the goods of body, soul, or fortune; and therefore to manifest such a secret without cause is the same as cooperating unjustly with the damage of the neighbor. - But the gravity of the sin depends on the gravity of the damage which is foreseen or can be foreseen.

(B) A committed secret obliges even more strictly from justice; for in this case there is a true contract, explicit or implicit, by force of which the one hearing the secret obliges himself to preserve it inviolably; if therefore he manifests it without reason, he harms the neighbor and society: (a) the neighbor, because he violates the strict right which the latter has that the secret be preserved, which was not revealed except under the condition of guarding it faithfully;¹ (b) society; for the common good demands that all may safely seek counsel or aid from those who, from office or by title of special friendship, are able to offer it; but men would be deprived of this utility if a committed secret could be manifested without grave cause; for who would confidently approach a physician, advocate, priest, and disclose to him secrets whose manifestation can harm him, unless he were certain that the same would be guarded inviolably?

¹ Hence civil laws affect violators of professional secrecy with severe penalties; cf. Cod. pen. gal., art. 378; Supplement, p. 72*.

420. Second principle: Those who violate a merely promised secret without cause sin against justice or fidelity, according to the intention of the one promising.

For he who promises something can bind himself in two ways: from justice indeed, if by explicit declaration, or implicitly from various circumstances, he manifests his intention of obliging himself thus; from fidelity, if he does not wish to undertake such an obligation, but only intends to confirm words by deeds. In the former case, the promise of itself obliges under grave sin, provided the matter is grave; in the latter, it binds only under light sin. Yet it must be noted that it is unworthy of an honorable man to violate these promises without reason.²

² "There could not exist a society, in fact, which does not rest on this firmly established principle: that every word given is sacred... What should one think of a man who has several words, or who has no word, for it is all one? In vain he lavishes his word of honor; it has no value in the eyes of anyone. Can one imagine a more certain sign of moral decline?" (Marion, Lecons de Morale, 11th ed., Paris, 1901, p. 269-270.)

I said merely promised, because it happens not rarely that a promised secret is at the same time natural, because it cannot be revealed without damage; then it obliges from justice, according to what was said above.

421. III. On the causes excusing from revelation of a secret. These ought to be greater the stricter the obligation is of preserving it; but this obligation depends on two things: (a) on the nature of the secret; for from what has been said, a committed secret obliges more strictly than a merely promised secret; and that which is at the same time natural and committed binds more strictly than a merely natural one; (b) on the damage inflicted: the graver and more irreparable the damage inflicted by the manifestation of the secret is, the greater cause is required for revealing it. - With these things posited, there are four causes from which a secret can legitimately be manifested:¹

¹ Some thought that a secret can never be revealed, even for saving the life of a friend; Fenelon excellently refutes these, in a letter, hitherto unknown, to L. de Sacy, which E. Levesque, S.S., made public in the periodical Revue des Facultes Cathol. de l'Ouest, April 1902, p. 511-526; from which we excerpt these things: "The silence which you would keep and which would cause your innocent friend to perish is contrary to humanity, to Christian charity, to good faith, and to the security of men in society... It is true that the secret which was told to you is a kind of deposit... It is not at all a deposit of sincere confidence, but a trap which is laid for you to force you to be an accomplice in a crime. Now society, which has so much interest in the preservation of other deposits, and in inviolable fidelity concerning other secrets, has a capital interest that the fraudulent deposit of so criminal a secret not be guarded, and that this deceiving depositor be confounded in his own deception... It is true that fidelity concerning a secret is a virtue, but this virtue is inferior to humanity, to charity, to the general order of human society... I would not wish, however, that you turn the secret against that unjust man from whom you hold it. To avoid this inconvenience, say to your friend only what is absolutely necessary for saving his life. Say it only to him alone. Say it to him only by using all the power which friendship gives you and all that which is acquired for you by the singular service which you actually render him, in order to prevent him from avenging himself."

422. 1. The public good of civil or ecclesiastical society; for since the obligation of a secret was chiefly introduced on account of the public good, its obligation ceases when the public good demands the revelation of the secret, according to this: the safety of the commonwealth is the supreme law. But here there is question of a proportionately grave public good: therefore the damage threatening the commonwealth must be compared with the damage going to follow from the violation itself of the secret, and the lesser evil, with all things carefully weighed, must be chosen. Thus if someone under secrecy, even committed secrecy, knows another's plan of betraying a city, and cannot otherwise impede its execution, he can and ought to manifest it to authority; but light damage does not suffice, arising namely from the fact that some guilty person will remain unpunished.

423. 2. The good of him who handed down the secret; for he is not judged unwilling, since there is question of promoting his own good; thus if someone knows that another wishes to marry, although bound by a diriment impediment, and that this evil cannot otherwise be averted than by manifesting the impediment to his own priest. Yet the case of a secret which was committed by reason of public office is excepted (De Matrim., n. 200): for then the public good demands that such a secret be guarded.

424. 3. The good of an innocent third party, namely when grave damage to him cannot be averted in another way; e.g., if you know, even under secrecy, that snares are being unjustly prepared for Titius, and that his death cannot otherwise be impeded than by revealing the secret, it is licit to do this; for charity demands that we impede grave damage to an innocent person even with damage to the guilty. - But if there is question of a committed secret, it is not licit to manifest it, unless the damage to be inflicted is from him who committed the secret; for, if it were revealed in other circumstances, the public good could be injured, as was explained above; but on the supposition that the one committing the secret himself wishes to kill or wound an innocent person, he now becomes an unjust aggressor, and the innocent person can be warned to beware for himself.¹

¹ Yet in many regions this is prohibited to those who have received the secret from office; thus physicians are forbidden to reveal a hidden contagious disease even to relatives.

425. 4. One's own good, namely when he who heard the secret cannot flee grave damage except by manifesting the secret; for he is not judged to have obliged himself with so great an inconvenience.

Yet the matter becomes more difficult if there is question of a committed secret; e.g., Caius is falsely accused of homicide, whose author he knows from a committed secret: can he manifest him, in order to spare his own life? - It is answered affirmatively if the author of the crime falsely accused him to whom he committed the secret: for then he is an unjust aggressor. But if the calumny proceeds from another source, it is controverted; each opinion seems probable; in practice the name of the guilty man can be manifested, if he is first warned that he should provide for himself by flight: for then he cannot complain.

But when the common good demands that a hidden matter be altogether preserved, even with the greatest private damage, - e.g., if the guarding of the secret is necessary for the security of the State or army, - it is necessary to die for the fatherland rather than betray the secret.

426. IV. Corollaries. 1. He who without legitimate authority and just cause maliciously investigates or extorts the secrets of another, of itself sins gravely against justice.

For each one has a right to his own secret: for nothing is more proper to man than the hidden things of the heart; now that right is injured as often as another maliciously, that is, through force, deceit, or fraud, tries to fish out these secrets. - But the gravity of the sin depends on the very gravity of the hidden matter which is thus extorted.

It was said (a) without legitimate authority; for superiors, whether ecclesiastical or civil, can and ought sometimes to investigate secrets on account of the common good; thus Bishops inquire concerning those to be ordained whether something is known against them; likewise magistrates from office can and ought to uncover crimes even hidden ones.

(b) Without just cause: for if it is licit to manifest a secret for averting grave damage, from what has been said above, by that very fact it is licit to investigate it; e.g., if someone were very probably to suspect that snares were being unjustly prepared for him, he would have the right of investigating the matter, and of exploring the secret counsels of adversaries: for this is the case of legitimate defense.

427. 2. He who justly or unjustly uncovers the secrets of another cannot use them to the damage of the neighbor; e.g., if someone by chance hears others conversing about a new invention, still hidden, he cannot use this knowledge for his own advantage; for otherwise he inflicts injury upon them, because they will no longer be able to obtain the exclusive privilege to which they had a right. A fortiori if, by unjustly opening another's letters, you know that some office is vacant, you cannot seek it with the damage of another: for thus you would deprive another of the legitimate hope of obtaining the same.

428. 3. From this it can be understood what must be said concerning the violation of a secret contained in letters.

(A) Of itself it is a grave sin to open and read another's letters, without the consent of him to whom they were written. For often secrets, some of which can be of great moment, are contained in these letters, e.g., matters pertaining to family, to business, or to conscience; and therefore by reading these letters without license, one exposes himself to the danger of unjustly knowing a secret of great moment.

429. (B) Yet the sin will be light: (a) if it is reasonably presumed that in these letters nothing is to be found except what is of lesser moment, e.g., if someone already knows the nature of the matters which are usually treated between two friends; (b) if the letters are opened or read from levity of mind, or without full advertence, and the reading is interrupted as soon as it is noticed that the matter is grave.

(C) But there will be no sin: (a) if express or tacit consent is present, - which nevertheless ought not easily to be presumed, - e.g., if spouses or friends are accustomed to hand over to one another to be read the letters which they receive from a common friend; (b) if in certain communities or colleges it is licit for the superior, from received custom or rule, to read the letters of subjects; for then the inferiors, by accepting the custom or rule, give tacit consent; yet letters sent to major superiors or received from them are excepted, and also those in which secrets of conscience are opened, from the reading of which the superior ought to abstain; (c) if the reading of some letter is necessary for averting damage threatening the commonwealth or private persons, according to what was said above.

430. (D) If letters have been thrown away by the owner, or knowingly left in a public place, they can be read without injustice, because he is deservedly judged to have renounced his right; but otherwise, if this happened against his intention.

But what if the owner tore up the letter and threw away its fragments? Not a few theologians hold that it can be read without injustice, because by so acting the owner renounced his right.¹ But much more probably others teach that this is not licit; for by tearing up the letters, he sufficiently signified that he did not wish them to be read by others, and therefore did not renounce his right.²

¹ Layman, lib. III, tr. III, p. 1, c. 4, n. 4; Lugo, d. XIV, n. 150; Vogler, n. 388.

² St. Alphonsus, lib. II, De peccatis, n. 70, with the authors alleged there.

Neither the duty of telling the truth nor the virtue of veracity, demand that we disclose everything that we know always or to all men. On the contrary, we are sometimes bound to withhold knowledge or information from others.¹ This brings us to the consideration of secrets.

¹ St. Thomas, Summa Theol., 2a 2ae, qu. 40, art. 3: “A will would be disordered if someone wished nothing to be concealed from him by others.”—Gury, Comp. Theol. Mor., Vol. I, n. 484: “A secret is knowledge of some matter which by its own nature or by a special contract must be kept hidden.”

1. A secret (secretum) is something hidden or concealed, or, more properly, knowledge or information which we are in duty bound to keep from others.

There are various kinds of secrets. a) A secret is called natural (secretum naturale) if a man has accidentally or inadvertently or purposely through his own efforts (secretum extortum) obtained a knowledge of something which he may not reveal to others without violating justice or charity, or which the one concerned has a right to hide. The latter category includes everything that cannot be revealed without injury to the honor, reputation, or property of others. If a crime can be prevented, or an injustice righted by the revelation of a secret, it may be revealed, but only to those who are in a position to act effectively, for instance, parents and superiors. b) The duty of keeping a secret sometimes rests upon positive grounds, as when a secret has been communicated or entrusted to one in an official capacity, or for safe-keeping under promise of silence. To the former class (secreta commissa) belong the so-called official or professional secrets, i. e., communications made to a man solely because of his official station or office, or communications made because of knowledge he has obtained by means of official functions or by participation in debates or trials. c) The promised secret (secretum promissum) arises from the fact that one has, through one’s own efforts, obtained a knowledge of a secret and then bound himself by a promise to keep it from others.

If a man comes for professional advice to another, as to a lawyer or a doctor, or simply to a friend for moral counsel, and in order thereto imparts to him natural secrets, those secrets, as they are received and held by the person consulted, are called secrets of trust or privileged secrets, be- cause, in contradistinction to natural secrets and secrets of promise, they need not be delivered up at the demand of an authority empowered to inquire in the department in which the secret lies.

The highest kind of privileged secret is that called sacramental. It is protected by the seal of confession (secretum sacramentale, sigillum confessionis) and arises from the Sacrament of Penance.²

² Cfr. this Handbook, Vol. II, pp. 167 sqq.—J. P. Gury, Comp. Theol. Mor., Vol. I, n. 485, 488; Irish Theol. Quarterly, Vol. V (1910), No. 17; Vol. VIII (1913), No. 29, No. 31.

2. The duty of keeping secrets needs to be more accurately circumscribed. a) Broadly speaking, a man is bound to keep every secret of which he has knowledge. To divulge a secret of any kind without urgent reason is a sin against both charity and justice, the guilt of which is measured, first, by the malice involved in the act, and, secondly, by the importance of the secret divulged and the injury inflicted by its revelation.

It is sinful to induce others to violate the duty of secrecy, especially if it is done maliciously or by force.

More particularly, the obligation of secrecy is gauged by the nature of the secret. The seal of confession by its very nature binds absolutely and always. So-called natural secrets are based upon the obligation of justice, which man owes his fellowmen, and which admits of exceptions for just reasons, and does not exclude silent reservation.

Silent reservation is admissible also in regard to committed or entrusted secrets, nay, even in regard to secrets promised under oath.³

³ J. P. Gury, op. cit., I, n. 486: “Question I: What are the just causes for disclosing a secret? Answer: (1) The rightly presumed consent of the person whose interest it is to conceal the secret; (2) disclosure of the matter made from another source; (3) harm that would follow from the secret to the commonwealth or to private persons; indeed, a grave obligation to reveal the secret sometimes presses, especially by reason of the public good. Question II: Can you reveal a secret if you have promised to keep it even at the cost of your life? Answer: (1) Affirmatively, if the common good demands it, because a promise made against the common good is null; (2) negatively, if it concerns your own merely grave harm, because it is better to keep the secret promised by this special contract. More probably negatively even if it concerns your own extreme harm, because you expressly renounced your right, and it is not unlawful to omit the preservation of life in order to keep your promise. Nevertheless St. Alphonsus [l. III, n. 971, ed. Gaudé, II, 361] rightly says that the contrary is sufficiently probable.”—Reg. Iuris in VI° Decr. Bonifacii VIII, n. 69: “In evil promises it is not expedient to keep faith.”—Cfr. this Handbook, Vol. IV, p. 260, n. 16.

The obligation of keeping professional or official secrets rests upon fidelity, without which the social order could not exist, and can therefore be modified only by the exigencies of public welfare. b) Apart from the seal of confession, which, as we have said, binds absolutely and at all times, the obligation of keeping a secret ceases whenever there is a just cause or excuse for disclosing the same, that is to say, when the secret has become publicly known without the co-operation of him who knows of it, and the welfare of any of the parties concerned in it or the public interest require that it be revealed. This would be the case, for instance, if an innocent man were to suffer serious injury unless a secret were disclosed or if a criminal could be reformed by divulging it.

Generally speaking, the obligation of keeping a secret does not hold before the law if the secret involves matters which may not be legitimately concealed, e. g., unjust plots against others or against the commonwealth, abuses and faults which cannot be corrected without publicity, etc.

In such cases it makes no difference whether an oath is involved or not.

Parents, guardians, teachers, and other legitimate superiors are allowed, by opening letters or by other means, to procure a knowledge of things which their children or subjects illegitimately wish to conceal from them.⁴ The public authorities may, for reasons strong enough to justify the use of force, examine the correspondence of suspected persons.

⁴ Gury, Comp. Theol. Mor., I, n. 487: “The question is whether one sins gravely by opening or reading another’s letters. Answer: Affirmatively in itself. The reason is that by natural law and the law of nations there is an obligation to leave the secrets of letters inviolate; otherwise human intercourse would be ruined. Except the following cases: 1. If there is the tacit or presumed consent of the one who writes or of the one to whom the letters are sent; 2. if it is known or presumed that the letters contain matters of lesser importance; 3. if it is done for a just cause, e. g., to avert public or private harm; 4. if the letters are opened from levity or mere curiosity.”—Cfr. St. Alphonsus, Theol. Mor., l. V, n. 70 (ed. Gaudé, II, 755).

Much has been said of late against "secret diplomacy," and justly so: but the fact remains that every government is allowed, nay obliged, to keep secret certain things which cannot be divulged without danger to the common weal. But those in authority may not employ such secrets to cover dishonest transactions, or to create false opin- ions, or to spread lying reports, or to engage in mendacious propaganda either at home or abroad, nor, in general, use any means apt to injure or undermine the public confidence.

For the individual it is not only a command of natural, and especially of Christian, prudence, but it may even be a grave duty to refuse to be made the repository of secrets which do not concern him, or to pry into the secrets of others.

“The main art of keeping a secret is not to talk about it. If a man is asked an awkward question, and sees no alternative but to let out or lie, it is usually his own fault for having encouraged the questioner up to that point. A wise man lets drop in time topics of conversation which he is unwilling to have pressed. He is never the first to introduce such topics. It is said of the ploughman in Ecclesiasticus, that his story is of the sons of bulls—enarratio eius in filiis taurorum. After all, cattle have no secrets, but men and women have.”⁵

⁵ Joseph Rickaby, S. J., Political and Moral Essays, p. 221.

Without strict necessity, letters should not be opened, nor should family secrets be exposed, or if necessity demands that it be done, the duties enjoined by truth and fidelity should be strictly adhered to.

Parents, guardians, and superiors should be cautious in making use of their right to pry into the secrets of their subjects, for if this is done without a just cause, it will encourage rather than stop underhand dealing.⁶

⁶ Linsenmann, Moraltheologie, p. 440.

For the rest it is well to remember that, in the words of a famous German poet, “two things are a detriment to him who wishes to ascend the ladder of happiness: namely, keeping silence when it is time to speak, and speaking when it is time to be silent.”⁷

⁷ Fr. Bodenstedt.

A positively untrue statement or denial is illicit, and mere silence often creates unjustifiable suspicion. Consequently, as it is often necessary to keep a secret, both for the sake of individuals and of society at large, moralists have devised ways and means by which illegitimate or curious questions can be evaded without lying or dissimulation. Of these ways and means the principal ones are: a) Amphiboly (ἀμφιβολία, doubt) or equivocation (aequivocatio), i. e., the use of equivocal or ambiguous expressions with the intention of being misunderstood by others. Usually in an expression of this kind the words reflect the thoughts of the speaker in such a way as to admit of a meaning different from the one that lies on the surface. Hence the speaker is not really the author of the ensuing deception, but the deception is the fault of the hearer, who could have perceived the true meaning had he paid closer attention to the words employed. b) Mental reservation or interior restriction (reservatio sive restrictio mentalis) may be subdivided into two species, namely: α) Pure mental reservation (restrictio sive reservatio pure seu stricte sive proprie mentalis) is the restriction of one’s meaning to the proposition as modified by some addition made to it within the mind of the speaker, the literal sense of which, therefore (verbum oris), is true only under the conditions retained in the mind (verbum mentis),—as if one, on being asked whether he did a certain thing, were to answer “No,” meaning, “Not in the way in which the questioner thinks, or at the time he means, or under the conditions he imagines, etc.,”—modifications which cannot be gathered either from the tenor of his words or the circumstances of the case.

Such pure or strict mental reservations are downright lies, because they aim at deception and effectively undermine the mutual confidence without which society can not exist.⁸

⁸ Gury, Comp. Theol. Mor., I, n. 457: “It is never lawful to use a purely or properly mental restriction, nor an amphibology not perceptible in a human manner; much less is it lawful to swear with them, because it is simply a lie.”—Cfr. the propositions condemned by Innocent XI, supra. Joseph Mausbach, Catholic Moral Teaching, pp. 79 sqq.; New York 1914; A. Meyenberg, Die katholische Moral, 2nd ed., pp. 180 sqq.; A. Adloff, Katholische Moral und Sittlichkeit, Strasbourg 1901, pp. 22 sqq.

β) Mental reservation in a broader sense (reservatio non pure sive late seu improprie mentalis aut sensibilis) is practiced if words are employed which are capable of being understood in different senses, either because they are in themselves ambiguous, or because they derive a special meaning from the circumstances of time, place, or person in which they are spoken, or, to put it somewhat differently, if the speaker really means what he says, but expresses himself so guardedly that the person addressed can gather his true intention only by taking his words in connection with the circumstances of the case. Thus when a servant says that his master is “not at home,” the words may mean either that he is absent or that he does not wish to receive visitors.⁹ With this kind of reservation, therefore, the true meaning of the speaker is not contained in the bare words, but may and must be gathered from the meaning which the words acquire from the circumstances in which they are spoken. Consequently, broad mental reservation is merely a species of equivocation, which, though by some authors called internal reservation, is in reality not such, because nothing is concealed.¹⁰

⁹ Slater, Moral Theology, I, 468.

¹⁰ Gury, Comp. Theol. Mor., I, n. 456: “Equivocations or amphibologies are also referred to restriction; these are expressions having a twofold principal sense, but one more obvious and the other less so, or even one spiritual and the other literal.”

In English, which is not the language of a Catholic people, and in which words mean, not what we would have them mean, but what they commonly mean in educated non-Catholic society, equivocation denotes a practice which is certainly wrong, and carries all the guilt of lying. “What ordinary Englishmen call equivocation,” says Fr. Rickaby, “corresponds to that which Catholic divines know as pure mental reservation, and that is a cowardly fashion of lying. Where aequivocatio is mentioned with approval in a page of Latin casuistry, the word ought to be translated, broad mental reservation. To render it equivocation is to create confusion, just as much as if one should render the canonical appeal, peto apostolos, “I ask for the Apostles,” or the old French, entre chien et loup, “between a dog and a wolf.”¹¹

¹¹ Political and Moral Essays, pp. 217 sq.

Examples of aequivocatio are pointed out in Holy Scripture. Thus Abraham and Isaac represented their wives as their sisters,¹² Jacob deceived his father to obtain the paternal blessing, and Judith gained admittance to Holofernes’ tent by means of a ruse.¹³ But the statements concerned, with the exception perhaps of those attributed to Abraham and Isaac, though literally mendacia, are to be regarded rather as mysteria,¹⁴ and therefore prove nothing either pro or con with regard to the question under discussion.

¹² Gen. XII, 11–19; XX, 2, 11 sqq.; XXVI, 7; XXVII, 1–35.

¹³ Judith X, 12 sqq.

¹⁴ St. Augustine, Contra Mendac., c. XI, n. 24: “What Jacob did with his mother as instigator, so that he seemed to deceive his father, if it is considered diligently and faithfully, is not a lie but a mystery. If we call these things lies, all parables and figures signifying any things whatsoever, which are not to be taken literally but in which one thing is to be understood from another, will also be called lies—which be altogether far from us.” (Migne, P. L., XL, 533).—St. Thomas, Summa Theol., 2a 2ae, qu. 110, art. 3, ad 3.

In the New Testament, Christ Himself repeatedly employed broad mental reservation, as when He called John the Baptist “Elias,”¹⁵ when He said that the daughter of Jairus was “not dead but sleeping,”¹⁶ and when He declared that if the Jews would destroy “this temple” (meaning His body), He would raise it up again in three days.¹⁷ It sounded like a mental reservation when He said that “the Father is greater than I”;¹⁸ that neither the angels nor the Son know the day or the hour of the Last Judgment;¹⁹ or when He declared that He would not go up to Jerusalem, and then went up anyhow.²⁰ It is obvious, however, that by employing such ambiguous language, our Lord did not wish to conceal the truth, or to mask His real intentions, but merely to indicate that His words bore a deeper meaning than that which lay on the surface. All that can be concluded from the passages in question is that ambiguous language is not per se forbidden. Broad mental reservation, therefore, must not be unreservedly condemned as illicit.²¹ However, it is not allowable under all circumstances, but only when (a) it does not embody a positive untruth, as is supposed; (b) when the true nature of the statement is recognizable, and (c) when there is a morally justifiable reason for keeping a secret.²² Whenever, on the other hand, there is a positive duty to tell the truth, e. g., in taking an oath, testifying in court, making a contract, or instruct- ing others, and when there is no obligation of keeping a secret, equivocation or mental reservation may not be employed.²³

¹⁵ Matth. XI, 14.

¹⁶ Matth. IX, 24.

¹⁷ John II, 19.

¹⁸ John XIV, 28.

¹⁹ Mark XIII, 32.

²⁰ John VII, 8–10.

²¹ St. Augustine, Enarr. in Ps., V, n. 7: “Since it is one thing to lie and another to conceal the truth—indeed, one thing to speak falsehood and another to keep truth silent—if someone perhaps does not wish to betray a man even to this visible death, he ought to be prepared to conceal the truth, not to speak falsehood, so that he may neither betray nor lie, lest he kill his own soul for the body of another.” (Migne, P. L., XXXVI, 85).—St. Jerome, In Ezech., l. IV, c. 14: “He who questions fraudulently does not deserve to hear the truth, but is to be caught by his own heart.” (P. L., XXV, 118).—St. Bernard, Serm. in Ct., XLII, n. 6: “For the most part it is not expedient that everything we know about ourselves become known to everyone, and by the very charity of truth and truth of charity we are forbidden to wish that what would harm the one who learns it be made public.” (Migne, P. L., CLXXXIII, 900).

²² “‘What news, my Lord, from France?’ some one asked of a cabinet minister. ‘I don’t know,’ was the reply, ‘I have not read the papers.’ The story is Cardinal Newman’s. Here the sense of the I don’t know is restricted and reserved, internally in the mind of the speaker, and externally by the words added about the newspapers. It is a mental reservation of the broadest, such as no Pharisee could call a lie. Now suppose the reference to the papers omitted. It would still be very hard to call the I don’t know a lie. The reservation of official knowledge is still sufficiently apparent: no sensible man would expect that to be communicated by way of ordinary chitchat. Above all, when a topic has been forced upon one, and questions put that admit of no evasion, by an enquirer who has no right to ask, then surely any denial or disclaimer, however direct the form of words, must be qualified by the outward circumstances in which it is spoken. This qualification, unspoken, but not unsignified, will be, ‘secrets apart.’” (Jos. Rickaby, S.J., Political and Moral Essays, pp. 222 sq.)

²³ Gury, Comp. Theol. Mor., I, n. 457: “It is sometimes lawful for a grave cause to use restriction in a broad sense, that is, improperly mental restriction, and equivocal words from which the sense intended by the speaker can easily be understood. The reason is that this is not evil in itself, since one’s neighbor is not properly deceived, but his deception is permitted for a just cause; moreover, the good of society requires that there be a means of lawfully concealing a secret of great importance; sometimes no other means is available except equivocation or restriction in the broad or improperly mental sense. I said, for a grave cause, because if such restrictions were used without a grave and proportionate cause, no one could or would be willing to believe another; and this would result in the greatest harm to human society.”—Cfr. Kössing, Ueber die Wahrheitsliebe, pp. 112 sqq.

READINGS.—St. Alphonsus, Theol. Mor., l. III, n. 970–971 (ed. Gaudé, II, 360); l. III, n. 151–171 (ed. Gaudé I, 467 sqq.).—F. X. Linsenmann, Lehrbuch der Moraltheologie, pp. 438 sqq.—Aug. Lehmkuhl, S. J., Casus Conscientiae, Vol. I, 3rd ed., n. 972 sqq.—F. A. Göpfert, Moraltheologie, Vol. II, 7th ed., pp. 334 sqq.—Kössing, Ueber die Wahrheitsliebe, pp. 106 sqq.—V. Cathrein, S. J., Moralphilosophie, Vol. II, 5th ed., pp. 96 sqq.—P. Hötzel, Jakob und Esau, Munich 1881.—E. Recejac, De Mendacio quid senserit Augustinus, Paris 1897.—W. Protopopoff, Biblische alttestamentliche Fakta nach Beleuchtungen der hl. Väter und Kirchenlehrer, Kasan 1897.—J. Mausbach, Catholic Moral Teaching and its Antagonists, pp. 113 sqq.—M. Cronin, The Science of Ethics, Vol. II, pp. 77 sqq.—Jos. Rickaby, S. J., “The Catholic Doctrine of Lying and Equivocation,” in Political and Moral Essays, N. Y. 1902, pp. 215 sqq.—IDEM, Moral Philosophy, pp. 232–237.—J. E. Ross, C.S.P., Christian Ethics, pp. 264 sq., 140 sqq., N. Y. 1919.—J. H. Newman, Apologia, pp. 274 sqq., 349 sqq., 359 sqq.—J. Brodie-Brosnan, “Mental Restriction and Equivocation,” in the Irish Ecclesiastical Record, Dec., 1920, No. 636, pp. 461–469.

6. The sixth duty of a Doctor is of a different kind. There exists a tacit or implicit contract between him and his patients that he shall keep their secrets of which he becomes possessed in his professional capacity. It is always wrong wantonly to betray the secrets of others; but the Doctor is bound by a special duty to keep his professional secrets; and it is doubly wrong and disgraceful in him to make them known. For instance, if he has treated a case of sickness brought on by sinful excesses of any kind, he is forbidden by the natural law to talk about it to such as have no special right to know the facts. Parents and guardians are usually entitled to be informed of their children’s and their wards’ wrong-doings, that they may take proper measures to prevent further evil. Besides, the Doctor is properly in their service; he is paid by them, and, therefore, his contract is with them rather than with the children. He can, therefore, prudently inform them of what is wrong, but he cannot inform others.

175. Notion. Secret taken objectively is the hidden thing itself; but accepted subjectively it is knowledge of that hidden thing and the obligation of not betraying the knowledge received. Concerning this secret accepted subjectively there is treatment here.

Division. A threefold secret is usually distinguished:

1. A natural secret, which is an obligation of concealing something arisen not from contract, but from the very nature of the thing, because, namely, such a secret cannot be manifested without another being reasonably unwilling, even if no entrusting or promise has intervened. This natural secret indeed is again distinguished as either simple or extorted. A simple natural secret is that which someone knows either by chance or because of the levity or lack of consideration of another, e.g., someone by chance sees another's hidden disgraceful vice. - An extorted natural secret is that which someone has known after a crafty investigation has been made; e.g., someone by design investigates concerning the private life of another.

2. A promised secret is that which someone promised to another after knowledge of the matter had been received. This promise indeed can be given in a twofold way. a) Someone has already known another's secret matter from another source, and now promises him that the secret is to be kept. b) Someone has heard a matter from another without secrecy and afterward promises him secrecy. Therefore in a promised secret, knowledge of the secret precedes the promise, and that promise is (ordinarily) gratuitous.³⁴⁸

3. An entrusted or strict secret (anvertrautes Geheimnis) is that which was not communicated except after there had first been an implicit or explicit pact of keeping secrecy. If this pact was implicit or tacit, the secret is called official (Amtsgeheimnis), because it arises from an office undertaken. By such an official secret, e.g., physicians, midwives, counselors, etc., are bound. But if the pact was explicit, this secret is called a privately entrusted secret; e.g., Peter says to Paul: I wish to narrate to you a matter of great moment, provided you promise me strict silence. Paul, having promised silence, hears the matter. This secret is entrusted to him in a private way. - Stricter is the secret which obliges from an oath taken, such as, e.g., officials of the Roman Curia emit. But the highest degree of entrusted secret is obtained by the sacramental secret, or the confessional seal, concerning which there will be discussion in the treatise on penance. In an entrusted secret, knowledge of the secret follows the promise, and that promise is onerous.

³⁴⁸ Under promised secret, privately entrusted secret also is included by some authors, e.g., by D'Annibale, Haine.

178. Principle 3. A merely promised secret of itself ordinarily does not oblige except under light matter.

I say 1: a secret merely promised. For often a secret of this kind is also natural, and then the preceding principle must be applied. - I say 2: of itself it does not oblige; for by accident violation of a promised secret can be a grave sin, namely, if because of this violation grave damage is caused to the neighbor. - I say 3: ordinarily it does not oblige except under light matter; for it can happen (although rarely) that someone promises under grave matter that he will keep a secret; e.g., I promise you the secret so firmly that, if I break it, I shall pay 1000 francs. - The principle taken with these clauses is proved in this way: Violation of a promised secret is only violation of a gratuitous promise or of fidelity. But the virtue of fidelity, which is a certain part of truthfulness, does not oblige of itself except under light matter, as was said above, n. 165 and 170, concerning lying. Therefore violation of a promised secret of itself is only a venial sin. - Nevertheless, violation of a promised secret is greatly to be avoided, because quarrels and grave enmities often arise from it.

179. Principle 4. An entrusted secret obliges of itself under grave matter, and indeed more gravely than a natural and a promised secret.

The reason is 1. because in an entrusted secret there is always a contract (implicit or explicit) of not revealing those things which are known, and 2. he who violates an entrusted secret wounds the right both of the neighbor and of society. For the neighbor would not have revealed his secret except under the condition of faithfully guarding it. Besides, the good of society demands that all can safely seek counsel or help from those who, from a special office approved by public authority, are able to furnish it. But if those officials could, without a legitimate and urgent cause, reveal secrets entrusted to them, no one would now approach them; and this would certainly bring great inconvenience for the common good. - Hence civil Codes also gravely punish the wounding of an entrusted secret.³⁵⁰

As appears from what has been said, the obligation of diverse secrets is diverse. As a general rule it can be held:

A secret obliges according to the quantity of damage which is unjustly brought upon either the public good or private good from its violation.

³⁵⁰ Cf. German Penal Code § 300.

852. A secret, subjectively taken, is knowledge of a thing hidden from others and to be hidden, or the knowledge and obligation of not manifesting some hidden thing; objectively, it is the hidden thing itself and to be hidden, which can be very diverse: an invention of art or science, or some fact, for example that an office is vacant, or an unknown crime. In the present matter, secret is chiefly taken subjectively. It is threefold:

a) Natural, whose obligation arises without contract from the very nature of the thing, because it cannot be manifested without harm or displeasure of the neighbor, and accordingly without his being reasonably unwilling. Thus if by chance or by effort you know another's money laid away, an invention, or a hidden crime, it is not licit to manifest it.

b) Promised, whose obligation arises from a gratuitous promise following upon knowledge of the matter, or because someone has promised to keep it, even if the matter from its nature does not induce an obligation of secrecy; for example, if someone concerning a thing previously known or now already received, spontaneously or at a friend's request, promises silence.

c) Committed or rigorous, whose obligation arises from an onerous promise antecedent to the reception of the secret, or because it is committed under an express or tacit pact of keeping it and is thus accepted by another.

Namely, first, expressly or tacitly, it is promised that it is not to be revealed: expressly indeed if someone says that he will not manifest the matter except under the express condition that the other keep silence about it (a private secret, which is required on account of a private good); tacitly when from some fact it is clear that the matter is committed under secrecy and that the other accepts it thus, as if it is committed to someone who by office, by force of the duty he bears, or by the special title of kinship or friendship, is bound not to manifest it (an officious or professional secret, which is required on account of the public good), for example, to a counselor, physician, midwife, advocate, theologian, confessor, visitor, parents, friends, etc., to whom a matter is manifested only because it is supposed to be faithfully guarded by them.

Consequently a committed secret obliges in varying degree: less when it was committed wholly freely, more if to a private person for the sake of counsel, still more if to one established in office, most of all when it is committed to a counselor in a public cause.

853. Principles. - Everyone has a strict right to his own secret. That right is proximately founded partly in dominion over one's own thoughts and the fruits of one's own genius or labor, partly in the right to reputation and external goods, insofar as, namely, from a violated secret there can be harm to reputation or fortune, or ceasing gain; ultimately it is founded in the common good. Hence the right of secrecy is relative and limited. Therefore of itself it is illicit, and indeed gravely, 1. to explore a secret; 2. to manifest a secret; 3. to use knowledge of a secret.

I. To explore a secret is illicit without legitimate authority or a just cause. For a secret is another's thing; therefore one who illegitimately explores it, for example by force, deceit, or fraud, usurps another's thing and takes it away from its owner. The gravity of this sin depends on the gravity of the thing which is extorted.

Hence a) of itself and generally it is illicit to listen at a wall or door, or to open letters, or to break open a chest, or to corrupt servants or workers in order to know another's secret, even an invention of art or science.¹

¹ An invention of art or science can licitly be detected by art or study; but this properly is not directly to explore another's secret, but to devise a similar invention by one's own ingenuity, whereby another's secret indirectly becomes known.

b) From legitimate authority, superiors (bishops, magistrates, judges) sometimes can and ought to explore secrets on account of the common good, for example, for detecting crimes committed or to be committed; and parents can do so on account of the good of children and of the family.

c) From a just cause, for example to avoid unjust harm, whether proper, common, or of an innocent third party, it is licit to explore the secret of him from whom harm threatens, for example, a crime committed or probably to be committed against oneself or against an innocent third party, the forces and positions of enemies in a just war.

II. To manifest a secret of itself is illicit, as being against charity and at the same time against fidelity or justice, because it is apt to be done with harm or displeasure of another, or also violates a promise or pact.

III. To use knowledge of a secret for one's own advantage or that of a third party, against the owner's will, is illicit, especially if it is done with his harm; a fortiori it is illicit if someone has detected the secret unjustly, because it would be to continue injustice.

Unless, however, it is in those circumstances in which there is a sufficient just cause for exploring a secret. But one who by unjustly using another's secret, as by revealing it, has brought harm upon another, is bound to restitution.

854. What the obligation of secrecy is. - I. A natural secret obliges from justice, by reason of harm; and one who violates it without just cause commits a grave sin from its genus.

II. A merely promised secret of itself obliges from fidelity alone, by reason of a simple promise; and one who violates it without just cause commits a venial sin, unless he intended to bind himself from justice, or the secret is at the same time natural.

III. A committed secret obliges from justice, by reason of a special contract; and one who violates it without just cause therefore sins gravely, and indeed more gravely, other things being equal, than for a natural secret. Especially if the secret is officious, because the common good regularly demands that it be preserved inviolate: for it pertains to the common good that all may safely seek counsel or help from those who by office or special title are able to furnish it. Hence such a secret ought not to be manifested to a judge or superior interrogating, and it also obliges if otherwise it would have had to be manifested; so that it is never to be revealed unless the common good demands it and by the law of nature it must altogether be revealed.²

² St. Thomas, II-II, q. 70, a. 1, ad 2.

855. There is a threefold just cause for manifesting a secret, on account of which the obligation of secrecy ceases:

1. The consent of him whose secret it is, at least reasonably presumed; for example, if a subject is denounced under secrecy, the superior can manifest, not indeed the denouncer, but the offense, in order to correct the delinquent.

2. Divulgation of the matter made from elsewhere; hence it is licit for him who had otherwise known a committed secret to speak about the secret, or to speak with a man who has knowledge of it.

3. The necessity of averting harm: generally it is licit to reveal a secret whenever this revelation is necessary for averting proportionately grave harm, public or private, proper or another's; indeed charity and legal justice sometimes require this manifestation. But a greater necessity is required the stricter and graver the obligation of keeping the secret is, which depends both on the nature of the secret and on the harm to be brought by manifestation.

But a fourfold necessity is given on account of which it is licit to manifest a secret as much as is sufficient for averting harm:

a) Grave common harm of civil society or of the Church: for the obligation of secrecy, which is principally introduced on account of the public good, ceases where the public good requires the manifestation of the secret, according to the adage: the safety of the republic is the supreme law. Therefore not just any harm to be avoided suffices, for example from the fact that otherwise some guilty man remains unpunished, but urgent necessity from a most grave impending harm.

Thus if someone under secrecy, even committed secrecy, has known another's purpose of greatly harming the city or the Church, from which he cannot otherwise be recalled, he can and ought to reveal the secret to authority. So also a physician is bound to denounce a sick person who could easily infect others gravely.

b) Grave harm of the very person committing the secret: for then he cannot be reasonably unwilling.

Thus, to prevent a marriage from being invalid, a hidden impediment which someone has known under secrecy must be revealed to the proper priest.

c) Grave harm of an innocent third party to be averted by revelation of the secret of the harmful person: for charity demands that we prevent grave harm of an innocent person, even with harm of the guilty person.

Yet if the matter concerns a committed secret, especially an officious one, it will not be able to be manifested unless the harm is still to be inflicted and by the very person who committed the secret about the harm to be inflicted. For the common good regularly requires that such a secret be kept, except in the case in which the one committing it is himself an unjust aggressor, against whom the innocent person can be defended. Thus if someone from a committed secret should know Peter to be a murderer, he could not reveal the matter to free Paul unjustly accused; yet he could do so if the accusation had been made by Peter himself. Likewise a physician, knowing by professional secrecy that a bridegroom is infected with venereal disease, could manifest the matter to the deceived bride, indeed he ought to do so, if the bridegroom, having been warned, would not desist from marriage.

d) Grave proper harm, for example danger of death, even if similar grave harm threatened another: for no one is judged to have bound himself with so great an inconvenience, unless he has expressly promised it and the promise was valid.

Yet if the matter concerns a committed secret, it will not be able to be manifested with great harm (for example, of life) to the one committing it, unless the danger comes from him, because then he is an unjust aggressor; otherwise, however, it is illicit. But in practice, the one committing it can first be warned about taking precautions against the harm which threatens him from the revelation to be made. Thus one who is falsely accused of homicide, whose author he knows from a committed secret, if it is necessary, can reveal the name of the guilty person after he has warned him to protect himself by flight.

Let it be noted that a secret can never be manifested, even for averting a most grave harm of death, proper or another's, if the common good demands that the hidden matter be wholly kept, as if the custody of the secret is altogether necessary for the security of society or of an army. Thus the secret of the seal of the sacrament of Penance can never be violated, because the greater good of religion and the salvation of the faithful always demands that it be preserved inviolate.

856. Corollary: on the secrecy of letters. - To open another's letters, or to read those already opened and kept in a closed place, for example in a desk, or lost by chance, of itself is a sin grave from its genus against justice: for everyone has a strict right to his own secret; and one who explores it without the owner's consent acts after the manner of a thief.

1. Hence they sin gravely who intend to know in this way secrets of great importance (matters regarding family, business, or conscience), or expose themselves to the danger of knowing them.

2. Nevertheless the sin will be only slight: a) of itself, if it is morally certain or can reasonably be presumed that nothing is found in these letters except matters of lesser importance, such as greetings, narrations of lesser events, commercial notes, and that grave infamy or grave harm cannot arise therefrom; b) accidentally, if letters are read from levity of mind or without full advertence, for example, to know news, to laugh at a barbarous manner of writing, and the reading is interrupted as soon as it appears that the matter is grave.

3. There will be no sin: a) if the consent of the sender or recipient is present, express or tacit, which nevertheless is not easily presumed: thus if spouses or friends are accustomed to hand over to each other letters received from a common friend to be read; b) in communities, institutes, or colleges in which it has been established by law, rule, or custom that superiors can read the letters of inferiors; in which case, however, letters sent to higher superiors are exempted, and in other letters those parts which it is clear deal solely with secrets of conscience; c) if on account of entirely grave motives someone judges that the letters contain injury, and the reading is necessary for averting harm threatening himself or others or the republic: nevertheless he will not be able to read more than the end requires. Thus in time of war it is licit for combatants to intercept the letters of enemies; likewise parents can read the letters of children, the rector of a college those of students, the rector of a prison those of the justly detained, a religious superior those of subjects; but not a master the letters of servants, nor a husband the letters of his wife, unless they judge with moral certainty that something harmful is contained in them.

4. Letters thrown away by the owner or knowingly left in a public place can be read without injustice, because he is deservedly judged not to vindicate his strict right; yet if something is contained there which, if revealed, would turn to the detriment of the owner, by reason of harm it must be kept hidden. But to read torn letters whose fragments are thrown away is not licit, at least if they are torn into pieces so small that the parts cannot be compared and the letter read except by an exquisite diligence which men are not accustomed to employ. For such tearing, by common estimation, is as it were destruction.

5. One who has acquired knowledge of a secret by unjustly opening letters nevertheless seems able to use it when circumstances have so changed that he now has the right of procuring for himself knowledge of that secret.

Here a secret is called whatever, either from its own nature or from a special contract, ought to be kept hidden. - A threefold secret is distinguished and is 1st. natural, if it is imposed by the very nature of the thing to be hidden, e.g., if you know something which you cannot manifest without grave injury to another either in estimation or in goods, etc.; 2nd. promised, if someone, hearing a secret from another or learning it by chance, promises that he will not reveal it; 3rd. committed, if someone manifests something to another and at the same time tacitly or expressly requires silence from him concerning it.

I say 1st. A natural secret in a grave matter obliges under grave matter, and indeed in justice, unless a just cause excuses. The reason is that from revelation of the secret harm follows to the neighbor, who has the right not to be injured without reasonable cause.

I say 2nd. A promised secret, besides the obligation of a natural secret, which by reason of the matter it can sometimes bring with it, by force of the promise alone obliges gravely or lightly according to the intention of the one promising; lightly, if the one promising binds himself only from fidelity, as often happens; gravely in grave matter, if he wished to oblige himself in justice.

I say 3rd. A committed or communicated secret, which is also called rigorous, obliges under grave matter in justice, and indeed more strictly than a merely natural secret and also than a promised one; because besides the natural obligation there also presses an obligation from an onerous contract expressly or tacitly undertaken. - Cf. St. Alphonsus, n. 970. - Baller., note (a) and (b), p. 440.

Albert, a Catholic physician, consults Caius the priest concerning the obligation of preserving a secret; for he says that recently the matter has been greatly agitated among physicians and that they do not all agree among themselves. For while, he says, some say that a woman who had consulted a physician in order to procure an abortion is to be denounced to the police officers, others, on the contrary, assert that the secret of any client of sound mind is never to be disclosed to anyone without his consent; and the civil judges themselves doubt whether a physician who in court refused to disclose a secret entrusted to him should be punished as contumacious. Hence Albert wishes to know the Catholic doctrine concerning secrets to be preserved, and specifically whether he can or is bound to denounce a woman who had asked him for a medicine by which she could procure an abortion. Hence it is asked:

1. What are the various species of secrets?

2. Can the several kinds of secrets be disclosed, and when?

3. What does our municipal law establish concerning this matter?

4. What is to be said of the case?

1. This question is answered on p. 337.

2. This question is answered on p. 338.

3. What does English law lay down on this matter? “Professional communications between counsel, solicitors, or their clerks, and their clients, made in confidence, can not be disclosed without the client's consent, nor can a client be compelled to disclose any communication made in confidence to his professional adviser.”¹ It is said that the case of privilege does not extend beyond the persons here mentioned, but doubts have been expressed in court whether doctors and clergymen can be compelled to disclose what has been told them professionally in confidence. Moreover, “a witness can not be asked, and will not be allowed to state, any facts, or to produce any documents, the disclosure of which may be prejudicial to the public interest, e.g., in the case of some high documents of State.”²

1 Indermaur, Principles of the Common Law, p. 471.

2 The same work, p. 476.

4. The case. Whatever English law may say on the matter, in the forum of conscience a doctor may not denounce to the authorities a woman who has asked him to give her medicine to procure abortion. Her criminal intention is only known to him as a professional secret, and such a secret he should faithfully keep when it refers to a past act. He should tell the woman what a crime she is guilty of in intention at least, and do what he can to deter her from committing it. He may threaten to inform against her if she attempts it, and if he can not prevail on her to give up the idea of procuring abortion, he will be justified in informing those who can prevent it, and even the public authorities, as there is question of saving the life of the innocent child which is threatened by the person whose secret is in question. In those circumstances the right to the secret lapses.