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Lying, as defined by St. Thomas Aquinas , is a statement at variance with the mind . This definition is more accurate than most others which are current. Thus a recent authority defines a lie as a false statement made with the intention of deceiving. But it is possible to lie without making a false statement and without any intention of deceiving. For if a man makes a statement which he thinks is false, but which in reality is true he certainly lies inasmuch as he intends to say what is false, and although a well-known liar may have no intention of deceiving others -- for he knows that no one believes a word he says -- yet if he speaks at variance with his mind he does not cease to lie.

Following St. Augustine and St. Thomas, Catholic divines and ethical writers commonly make a distinction between (1) injurious, or hurtful, (2) officious, and (3) jocose lies. Jocose lies are told for the purpose of affording amusement. Of course what is said merely and obviously in joke cannot be a lie: in order to have any malice in it, what is said must be naturally capable of deceiving others and must be said with the intention of saying what is false. An officious, or white, lie is such that it does nobody any injury: it is a lie of excuse, or a lie told to benefit somebody. An injurious lie is one which does harm.

It has always been admitted that the question of lying creates great difficulties for the moralist. From the dawn of ethical speculation there have been two different opinions on the question as to whether lying is ever permissible. Aristotle, in his Ethics , seems to hold that it is never allowable to tell a lie, while Plato, in his Republic , is more accommodating; he allows doctors and statesmen to lie occasionally for the good of their patients and for the common weal. Modern philosophers are divided in the same way. Kant allowed a lie under no circumstance.

Paulsen and most modern non-Catholic writers admit the lawfulness of the lie of necessity. Indeed the pragmatic tendency of the day, which denies that there is such a thing as absolute truth, and measures the morality of actions by their effect on society and on the individual, would seem to open wide the gates to all but injurious lies. But even on the ground of pragmatism it is well for us to bear in mind that white lies are apt to prepare the way for others of a darker hue.

There is some difference of opinion among the Fathers of the Christian Church. Origen quotes Plato and approves of his doctrine on this point (Stromata, VI). He says that a man who is under the necessity of lying should diligently consider the matter so as not to exceed. He should gulp the lie as a sick man does his medicine. He should be guided by the example of Judith, Esther, and Jacob. If he exceed, he will be judged the enemy of Him who said, "I am the Truth." St. John Chrysostom held that it is lawful to deceive others for their benefit, and Cassian taught that we may sometimes lie as we take medicine, driven to it by sheer necessity.

St. Augustine, however, took the opposite side, and wrote two short treatises to prove that it is never lawful to tell a lie. His doctrine on this point has generally been followed in the Western Church, and it has been defended as the common opinion by the Schoolmen and by modern divines.

It rests in the first place on Holy Scripture . In places almost innumerable Holy Scripture seems to condemn lying as absolutely and unreservedly as it condemns murder and fornication. Innocent III gives expression in one of his decretals to this interpretation, when he says that Holy Scripture forbids us to lie even to save a man's life. If, then, we allow the lie of necessity, there seems to be no reason from the theological point of view for not allowing occasional murder and fornication when these crimes would procure great temporal advantage; the absolute character of the moral law will be undermined, it will be reduced to a matter of mere expediency.

The chief argument from reason which St. Thomas and other theologians have used to prove their doctrine is drawn from the nature of truth. Lying is opposed to the virtue of truth or veracity. Truth consists in a correspondence between the thing signified and the signification of it. Man has the power as a reasonable and social being of manifesting his thoughts to his fellow-men. Right order demands that in doing this he should be truthful. If the external manifestation is at variance with the inward thought, the result is a want of right order, a monstrosity in nature, a machine which is out of gear, whose parts do not work together harmoniously.

As we are dealing with something which belongs to the moral order and with virtue, the want of right order, which is of the essence of a lie, has a special moral turpitude of its own. There is precisely the same malice in hypocrisy, and in this vice we see the moral turpitude more clearly. A hypocrite pretends to have a good quality which he knows that he does not possess. There is the same want of correspondence between the mind and the external expression of it that constitutes the essence of a lie. The turpitude and malice of hypocrisy are obvious to everybody.

If it is more difficult to realize the malice of a lie, the partial reason, at least, may be because we are more familiar with it. Truth is primarily a self-regarding virtue : it is something which man owes to his own rational nature, and no one who has any regard for his own dignity and self-respect will be guilty of the turpitude of a lie. As the hypocrite is justly detested and despised, so should the liar be. As no honest man would consent to play the hypocrite, so no honest man will ever be guilty of a lie.

The absolute malice of lying is also shown from the evil consequences which it has for society. These are evident enough in lies which injuriously affect the rights and reputations of others. But mutual confidence, intercourse, and friendship, which are of such great importance for society, suffer much even from officious and jocose lying. In this, as in other moral questions, in order to see clearly the moral quality of an action we must consider what the effect would be if the action in question were regarded as perfectly right and were commonly practiced. Applying this test, we can see what mistrust, suspicion, and utter want of confidence in others would be the result of promiscuous lying, even in those cases where positive injury is not inflicted.

Moreover, when a habit of untruthfulness has been contracted, it is practically impossible to restrict its vagaries to matters which are harmless: interest and habit alike inevitably lead to the violation of truth to the detriment of others. And so it would seem that, although injury to others was excluded from officious and jocose lies by definition, yet in the concrete there is no sort of lie which is not injurious to somebody.

But if the common teaching of Catholic theology on this point be admitted, and we grant that lying is always wrong, it follows that we are never justified in telling a lie, for we may not do evil that good may come: the end does not justify the means. What means, then, have we for protecting secrets and defending ourselves from the impertinent prying of the inquisitive? What are we to say when a dying man asks a question, and we know that telling him the truth will kill him outright? We must say something, if his life is to be preserved: he would at once detect the meaning of silence on our part. The great difficulty of the question of lying consists in finding a satisfactory answer to such questions as these.

St. Augustine held that the naked truth must be told whatever the consequences may be. He directs that in difficult cases silence should be observed if possible. If silence would be equivalent to giving a sick man unwelcome news that would kill him, it is better, he says, that the body of the sick man should perish rather than the soul of the liar. Besides this one, he puts another case which became classical in the schools. If a man is hid in your house, and his life is sought by murderers, and they come and ask you whether he is in the house, you may say that you know where he is, but will not tell: you may not deny that he is there. The Scholastics, while accepting the teaching of St. Augustine on the absolute and intrinsic malice of a lie, modified his teaching on the point which we are discussing. It is interesting to read what St. Raymund of Pennafort wrote on the subject in his Summa , published before the middle of the thirteenth century. He says that most doctors agree with St. Augustine, but others say that one should tell a lie in such cases. Then he gives his own opinion, speaking with hesitation and under correction. The owner of the house where the man lies concealed, on being asked whether he is there, should as far as possible say nothing. If silence would be equivalent to betrayal of the secret, then he should turn the question aside by asking another -- How should I know ? -- or something of that sort. Or, says St. Raymund, he may make use of an expression with a double meaning, an equivocation such as: Non est hic, id est, Non comedit hic -- or something like that. An infinite number of examples induced him to permit such equivocations, he says. Jacob, Esau, Abraham, Jehu, and the Archangel Gabriel made use of them. Or, he adds, you may say simply that the owner of the house ought to deny that the man is there, and, if his conscience tells him that this is the proper answer to give, then he will not go against his conscience, and so he will not sin. Nor is this direction contrary to what Augustine teaches, for if he gives that answer he will not lie, for he will not speak against his mind ( Summa , lib. I, De Mendacio ).

The gloss on the chapter, "Ne quis" (causa xxii, q.2) of the Decretum of Gratian, which reproduces the common teaching of the schools at the time, adopts the opinion of St. Raymund, with the added reason that it is allowable to deceive an enemy. Lest the doctrine should be unduly extended to cases which it does not apply, the gloss warns the student that a witness who is bound to speak the naked truth may not use equivocation. When the doctrine of equivocation had once been introduced into the schools it was difficult to keep it within proper bounds. It had been introduced in order to furnish a way of escape from serious difficulties for those who held that it was never allowed to tell a lie. The seal of confession and other secrets had to be preserved, this was a means of fulfilling those necessary duties without telling a lie. Some, However, unduly stretched this doctrine. They taught that a man did not tell a lie who denied that he had done something which in truth he had done, if he meant that he had not done it in some other way, or at some other time, than he had done it. A servant, for example, who had broken a window in his master's house, on being asked by his master whether he had broken it, might without lying assert that he had not done so, if he meant thereby that he had not broken it last year or with a hatchet. It has been reckoned that as many as fifty authors taught this doctrine, and among them were some of the greatest weight, whose works are classical. There were of course many others who rejected such equivocations, and who taught that they were nothing but lies as indeed they are. The German Jesuit, Laymann, Who died in the year 1625, was of this number. He refuted the arguments on which the false doctrine was based and conclusively proved the contrary. His adversaries asserted that such a statement is not a lie, inasmuch as it was not at variance with the mind of the speaker. Laymann saw no force in this argument; the man knew that he had broken the window, and nevertheless he said he had not done it; there was an evident contradiction between his assertion and his thought. The words used meant that he has not done it; there were no external circumstances of any sort, no use or custom which permitted of their being understood in any but the obvious sense. They could only be understood in that obvious sense, and that was their only true meaning. As it was at variance with the knowledge of the speaker, the statement was a lie. Laymann explains that he did not wish to reject all mental reservations.

Sometimes a statement receives a special meaning from use and custom, or from the special circumstances in which a man is placed, or from the mere fact that he holds a position of trust. When a man bids the servant say that he is not at home, common use enables any man of sense to interpret the phrase correctly. When a prisoner pleads "Not guilty" in a court of justice, all concerned understand what is meant. When a statesman, or a doctor, or a lawyer is asked impertinent questions about what he cannot make known without a breach of trust, he simply says, "I don't know ", and the assertion is true, it receives the special meaning from the position of the speaker: "I have no communicable knowledge on the point." The same is true of anybody who has secrets to keep, and who is unwarrantably questioned about them. Prudent man only speak about what they should speak about, and what they say should be understood with that reservation. Catholic writers call statements like the foregoing mental reservations, and they qualify them as wide mental reservations in order to distinguish them from strict mental reservations. These latter are equivocations whose true sense is determined solely by the mind of the speaker, and by no external circumstances or common usage. They were condemned as lies by the Holy See on 2 March, 1679. Since that time they have been rejected as unlawful by all Catholic writers. It should be observed that when a wide mental reservation is employed the simple truth is told, there is no statement at variance with the mind. For not merely the words actually used in a statement must be considered, when we desire to understand its meaning, and to get at the true mind of the speaker. Circumstances of place, time, person, and manner form a part of the statement and external expression of the thought. The words, "I am not guilty", derive the special meaning which they have in the mouth of a prisoner on his trial from the circumstances in which he is placed. It is a true statement of fact whether in reality he be guilty or not. This must be understood of all mental restrictions which are lawful. The virtue of truth requires that, unless there is some special reason to the contrary, one who speaks to another should speak frankly and openly, in such a way that he will be understood by the person addressed. It is not lawful to use mental reservations without good reason. According to the common teaching of St. Thomas and other divines, the hurtful lie is a mortal sin, but merely officious and jocose lies are of their own nature venial.

The doctrine which has been expounded above reproduces the common and universally accepted teaching of the Catholic schools throughout the Middle Ages until recent times. From the middle of the eighteenth century onwards a few discordant voices have been heard from time to time. Some of these, as Van der Velden and a few French and Belgian writers, while admitting in general a lie is intrinsically wrong, yet argued that there are exceptions to the rule. As it is lawful to kill another in self-defense, so in self-defense it is lawful to tell a lie. Others wished to change the received definition of a lie. A recent writer in Paris series, Science et Religion , wishes to add to the common definition some such words as "made to one who has the right to truth." So that a false statement knowingly made to one who has not a right to the truth will not be a lie. This, however, seems to ignore the malice which a lie has in itself, like hypocrisy, and to derive it solely from the social consequence of lying. Most of these writers who attack the common opinion show that they have very imperfectly grasped its true meaning. At any rate they have made little or no impression on the common teaching of the Catholic schools.


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