MENTAL RESERVATION. - I. NOTION AND HISTORICAL DEVELOPMENT. - Mental reservation consists in the interior act of the mind by which the person replying changes within himself—by restricting, enlarging, or otherwise modifying it—the meaning that his external reply plainly conveys to the person hearing II. Thus the reply assumes a double meaning: the external meaning, resulting from the verbal expression and the circumstances in which it is uttered; and the internal meaning, resulting also from the modification introduced into it by the mental act of reservation. The whole significance of mental reservation lies precisely in the double meaning of the reply, since, by virtue of its merely external meaning, it becomes possible to shield one’s inner thought from indiscreet inquiry. Whereas, by virtue of its internal meaning, the reply will not be at variance with one’s thought and therefore, since it does not constitute a lie, will be permissible.
Historical development of the question. - Caietanus (d. 1534) already reports the opinion of many authors of his time (In 2ª-2ª, q. 89, a. 7), an opinion which he nevertheless does not consider true, according to which it would be permissible to swear to an external assertion to which one adds « tacitam in mente conditionem, puta : si debeo »; for example, to make an external promise, confirming it if necessary even by oath, to deliver to a blackmailer the sum he has unjustly demanded, while adding mentally the condition: « If I am obliged ».
But not all authors agreed on this point. As long as the controversies remained within ecclesiastical circles, they were always conducted within the dignified bounds of scholarly seriousness and charity. But when, in the seventeenth century, laymen also took part in them, they degenerated into disorderly polemics, which both resulted from and provided an occasion for the venting of personal and partisan passions. Prompted by this situation, the Holy Office intervened and, in March 1679, condemned the doctrine of mental reservation in two propositions (Denz-U., 1176-77), at least as « scandalous » and « in praxi perniciosa ».
Following this condemnation, the advocates of mental reservation were compelled to revise their doctrine, which they reproposed within the following limits. A distinction, already proposed earlier by some authors, between mental reservation in the strict sense and mental reservation in the broad sense was reassessed. Mental reservation in the strict sense exists when, in the modification it introduces into the external meaning of the reply, no revealing traces appear either in its grammatical or syntactical structure or in the accompanying circumstances in which it is uttered. If, instead, some such traces appear, so that by virtue of them the reply comes to acquire a meaning that is equivocal even externally, there is mental reservation in the broad sense. In a rich and subtle casuistry, the nature, qualities, and limits of these equivocal traces were explained. Once this distinction had been stated and clarified, it was held that only mental reservation in the strict sense had been condemned by the Holy Office. Mental reservation in the broad sense, however, as not covered by the condemnation, continued to be upheld as a licit means of concealing one’s thought. Even the use of this means, however, was permitted only in cases of necessity—that is, when disclosure of one’s thought, owing to the malice or imprudence of others, constitutes a genuine danger of private or public harm.
In this definitive form, the doctrine of mental reservation is still accepted today by many treatises of moral theology.
II. CRITICAL JUDGMENT. — The principles from which the supporters of mental reservation proceed and the conclusions at which they arrive are undoubtedly sound. That is: the intrinsic unlawfulness of lying, whose essence consists entirely in the relation of opposition between the thought of the speaker and the expression by which he manifests it; the reasonable existence of lawful and effective means of concealing one’s thoughts in cases of necessity; and consequently, in such cases, the responses, in their obvious meaning, their equivocal meaning, or even their false meaning, cannot be condemned—unless one is prepared to renounce common sense. Such responses are certainly not lies, as was demonstrated elsewhere (v. MENZOGNA). But that the act of mental reservation is the reason why these responses are not lies is untenable.
And this is evident with regard to mental reservation in the strict sense. For such reservation could transform into a sincere response one that without it would be a lie only if it succeeded in changing either the thought of the person uttering it or its external expression; indeed, thought and external expression in opposition to one another are the essential constituents of a lie. Now, neither element is modified by mental reservation. Not the external expression of the response, because reservation in the strict sense operates only in the mind, without revealing traces externally. Nor does the thought of the person responding change, because it is in order to defend it in concealment, not to change it, that one has recourse to mental reservation. Moreover, at least with regard to mental reservation in the strict sense, the condemnation of the Holy Office remains in force. Its own defenders acknowledge this, limiting themselves to upholding mental reservation only in the broad sense. But this too does not withstand criticism.
Let it first be specified that mental reservation is understood in the broad sense insofar as it remains concealed in the mind only in part, while in its other part it is manifested through external elements that are more or less revealing. Now, as regards that part of the reservation which remains concealed in the mind, what was just said about reservation in the strict sense applies. For in both cases it operates only in the soul of the person responding, without producing any change either in his thought or in the external expression by which he manifests II.
As for the part of the reservation that appears in the external expression, granted, though not conceded, that it succeeds in making sincere a response that without it would be a lie, this would happen no longer by virtue of mental reservation but on account of the equivocal meaning that the response by then presents in itself. This is shown by the fact that, for the lawfulness of such a response, the authors do not consider the mere reservation of the mind sufficient, but require traces that make it in some way externally perceptible. And then the observation already made by Caramuel (d. 1682) in his Theologia fundamentalis (Frankfurt 1651, no. 1804) is entirely true. Whoever regards as mental reservation an expression that is equivocal in itself regards only the name as mental reservation; because, in such a case, the expression derives another meaning, in addition to its obvious meaning, not from the interior act of the mind but from elements contained in the expression itself.
The phrase “granted, though not conceded” was used because not even an expression that is equivocal in itself preserves the response from the unlawfulness of lying. But this is not the most suitable place to discuss the matter. Rather, we shall conclude with two observations: one practical, the other historical. The first is that the practical consequences arising from the doctrine of mental reservation are exceedingly objectionable. For while astute people would find in the easy use of equivocal devices a convenient way of escaping almost every lie, uneducated and simple people, merely because of their lack of skill in using words, would not have at their disposal the lawful means of defending their secrets. Yet it is self-evident that such a means must be accessible to everyone, indeed especially to the uneducated, whose inferior condition exposes them more readily to the snares of the clever. The second observation is that the paternity and advocacy of mental reservation are wrongly attributed to the Society of Jesus, with the consequent opportunity to denigrate II. Quite apart from the name, the doctrine of mental reservation was proposed and defended as early as the time of Cajetan (d. 1534) and Blessed Angelo da Chivasso (d. 1495), before the foundation of the Society (1540). Subsequently, moreover, many distinguished Jesuit theologians did not adopt II. For example, Suárez (d. 1617) regarded it as only probable in De religione (in Opera omnia, XIII, Paris 1859, tract. 5, chapters 9 and 10), while De Lugo (d. 1660) explicitly rejected it (De fide, d. 4, no. 62, Venice 1718, p. 99).