Summa Theologiae Moralis, vol. I: De Principiis

S. Th. I-II, q. 20, a. 5 ; q. 73, a. 8 ; q. 77, a. 7 ; II-II, q. 64, a. 7 and 8 ; q. 79, a. 3, ad 3 ; q. 150, a. 4 ; Quodl. IX, 15.

In human acts the external effect merits entirely special consideration, since, according as it is good or bad, morality can depend upon it, especially in an exterior act. For the doctrine on the morality of the effect is of the greatest moment in practice and as it were the key by which many and difficult cases must be solved, — such as cooperation, scandal, harming, etc. Now the following hold about this matter.

172. Principles on the morality of the external effect.

I. A good or bad effect, directly and in itself voluntary, is imputed to the agent for either goodness or malice, whence it increases the goodness of an otherwise good act, and the malice of an otherwise evil act; but if to an evil act a good effect is joined, this does not remove the malice of the act, although it can diminish it.

II. A good effect only in its cause or indirectly willed is not imputed for goodness, because good is not rightly done, as right reason dictates and as it deserves to be done, unless it is willed for its own sake, whence goodness is not contracted unless it is intended in itself (n. 146).

III. A bad effect in its cause or indirectly willed is imputed to the agent for malice, if three conditions are verified:

1. if it was in some way foreseen, at least in a confused way: nothing is willed unless it is first known;

2. if it could have been prevented, insofar as the cause could have not been placed, or, having been placed, removed — for the effect is not more voluntary than the cause;

3. if it ought also to have been prevented, i. e., there was an obligation of avoiding the effect, or of not placing the cause or of removing the cause so that the effect would not follow (nn. 60 and 63).

To prevent an evil effect, one can be bound either by office, e. g., parents or a teacher to drive away from the children committed to them wicked companions, lest they be corrupted; or by justice, as a guardian or administrator regarding the things or affairs entrusted to him; or by religion, as a consultor for the divine honor; or by every virtue, lest an effect directly contrary to it be produced; or by charity, which e. g. demands that you cry out lest another unknowingly fall into danger of life. — On the contrary, if you do not have necessary care of health, it will not be imputed to you that on some day you cannot fast, just as it will not be that you experienced a pollution because you ate meat on a forbidden day: for these are not precisely to be avoided so that such an effect does not follow.

173. Principle on the lawful manner of causing a bad effect. — Each virtue generally obliges to avoiding the cause that produces an evil effect opposed to it, e. g., harm to a third party, scandal, dishonest movements; but not always. It is lawful to place a cause that simultaneously produces a good and a bad effect, if the good effect follows from the cause at least as immediately as the bad, or not through the bad, and there is present a proportionately grave reason, with the two others always necessary being supposed, namely the action being lawful in itself, and the right intention of the agent.

Four things therefore are required: a) Two on the part of the effect, that the bad effect not be imputed; namely:

1. That the good effect follow from the cause at least as immediately as the bad, or not through the bad effect; otherwise this would be the means to obtain the good effect, whereas evils are not to be done that goods may come (n. 156, 5°): hence it is illicit to lie in order to save a man, to procure an abortion to avoid infamy, or to kill the fetus to save the mother's life, to steal money to give alms, etc.

2. That there be a reason for placing the cause, and indeed proportionately grave, i. e., that the good procured surpass or equal the evil: for reason dictates that one good is not to be procured in act from which a greater evil follows; — on the contrary, if the good compensates the evil, no reason appears why the evil should be avoided: thus it is not lawful to kill an aggressor to preserve goods of less value, it is lawful to preserve life. Hence the greater the malice of the effect, the greater must be the excusing reason; and it is always required that the good effect cannot otherwise suitably be obtained: otherwise there would no longer be a reason for bringing about the bad effect.

b) So that not only the bad effect not be imputed, but also that it be lawfully caused, or so that the action itself be honest, moreover two other things are required on the part of the action:

3. That the action in itself (i. e., setting aside the circumstances) not be bad, but honest or at least indifferent: for a cause in itself bad includes fault of itself.

4. That the end of the agent be honest, and therefore that the bad effect not be intended but only the good, otherwise it would be bad in itself voluntary or at least willed; whence it is also required that there not be a proximate danger of consenting to evil or approving it¹.

This principle, however, is not always rightly explained by everyone.

a) Some assert that it is not required that the good effect be immediate, but it suffices that it does not come through the bad, even if it is more remote. But this seems to be a question of manner of speaking: for then the possibility of obtaining the good effect already results immediately from the action and this already is a certain good effect.

b) Others understand the principle of the cause per se with respect to the good effect and of the cause per accidens with respect to the bad effect, so that the good effect must follow per se and as it were necessarily from the action, and the bad effect only per accidens. But, although in this case it can more easily be a reason for placing the action, or that there is a compensation of the bad effect by the good, it is not, however, proved that this is a sine qua non condition, so that otherwise one would have to abstain from the action. For it does not seem impossible to have a cause from which simultaneously per se would follow a twofold effect: one good, the other bad (say health, and drunkenness or abortion); which nevertheless it would be lawful to apply if it were necessary to obtain the good effect, provided this compensates the bad. Indeed if the bad effect followed from the cause per se, the good only per accidens, why could we not order that cause per accidens to obtain the good effect, if it would thus certainly be produced and truly preponderate over the evil? By such a restriction, therefore, the principle seems unduly limited.

c) Others finally apply the principle too materially, and seem to think that the good effect in itself considered must always be equal to the bad effect. But it suffices that the goodness of the effect, together with the utility which it procures for the agent or others, and the inconvenience and harm (which if the cause were not placed would arise) avoided, compensates the evil, i. e., not always the bad effect but at least the influence of the action on this effect: for the bad effect must be compensated by the agent because his action influences it, whence it must be compensated in so far as the action influences. Hence a graver reason is required for placing the cause:

1° the graver or worse the effect is, both in itself and with respect to the harm of others, especially of society; e. g., a greater reason is required for killing an aggressor than for lightly wounding, a greater one for producing a harmful effect on society than on an individual;

2° the more actively and necessarily the bad effect proceeds from the action, the more closely it coheres with it, and the more probably it follows from it; e. g., a greater reason is required for one who concurs proximately than for one who concurs remotely in another's sin (e. g., the making of a wicked book or drunkenness), a greater one for reading a wicked book than a book of lighter nature from which movements of concupiscence arise more remotely, a greater one for placing a per se cause than a per accidens cause; likewise a very urgent reason is required that a maidservant be able to exercise service in a house where she is often allured to sin by the son, a much less motive suffices if an outsider coming into the house now and then solicits;

3° the less right the agent has to place the cause and the more certain it is that, if he does not act, the effect will not be produced; i. e., the greater the obligation ex officio of preventing evil; e. g., a greater reason is required for letting a building to heretics if they can find no other than if they can easily rent one elsewhere, a greater reason for a bookseller to be able to sell a wicked book if no one else is found to sell it than if someone else is at hand to sell it.

All of which must be considered together, to prudently judge whether the good compensates the evil.

174. How great is the imputability of a bad effect. — For determining the gravity of the fault incurred by him who places the cause of a bad effect, the axiom holds: An effect voluntary in its cause is not more culpable than the cause itself. Which is not to be understood of the cause in itself and independently of the effect considered: for it can happen that an action in itself good, indifferent, lightly bad, contracts grave malice from the effect, e. g., if the throwing of a stone or a slight falsehood is the cause of homicide; on the contrary that an action in itself gravely bad has slight malice by reason of the effect, e. g., drunkenness which produces slight anger, homicide inflicting some other small harm. But it is to be understood of the cause considered as cause, i. e., insofar as it influences the effect; whence the nature and gravity are to be considered, both of the influence or causality, and of the effect itself. Hence

1. a cause which of itself, proximately, and gravely influences a bad effect, besides its proper malice which it perhaps has from itself, acquires in addition grave or light malice of the effect; whence a cause per se gravely bad, which proximately influences a lightly bad effect, has light malice superadded; on the contrary a cause per se lightly bad, which proximately influences a gravely bad effect, has grave malice from this;

2. a cause which of itself but lightly and remotely, or only per accidens, influences even a grave effect, by reason of the influence contracts only light malice, e. g., if from immoderate food or from drunkenness or from a delectation morosa not protracted a pollution follows. A small influence in a grave thing of itself is not something notable. Such a cause has, however, grave malice by reason of the effect, if this is strictly prohibited so that all things must be avoided which even lightly contribute to it (as happens in matters of justice, lest grave harm be inflicted on a neighbor), or if by reason of office or state there is a special obligation to avoid the effect². Thus drunkenness's influence on pollution is lightly, on homicide gravely culpable.

175. When the morality of the effect is contracted. — The whole goodness or malice of the effect is contracted inchoatively interiorly and as to the affect, when the cause is voluntarily placed, even if per accidens the effect does not follow: for then the effect is intended at least in a confused way; consummatively exteriorly and as to the effect, when the effect really occurs, unless at this moment the past will, as far as possible, has been retracted: for then the effect will be only materially good or bad.

176. Remark for understanding the doctrine of S. Thomas. — In q. 20, a. 5, briefly and with several other principles supposed, S. Thomas teaches several things about the morality of the effect, which can be understood from what has been said:

A. In the order of execution, the following event, willed, whether it follows or does not follow, does not add formal goodness or malice to the external action, just as « he does not make an act bad which was good, nor good which was bad; e. g., if someone gives alms to a poor man, who abuses it for sin, nothing is lost to him who gave the alms; and similarly, if someone suffers the injury done to him, he who did it is not excused by this ».

For morality depends on the voluntary. Whether the intended effect follows or is accidentally prevented is involuntary. Therefore it does not change the morality of the act.

B. In the order of intention about the event he teaches three things:

1. The following event pre-cogitated, i. e., distinctly foreseen and in some way willed³ (in that diverse manner which is required for contracting goodness and malice), increases the formal goodness or malice of the external act.

2. The following event not pre-cogitated, i. e., not distinctly foreseen, if per se as in many cases follows from such an action, directly adds to the goodness or malice of the act, which is better in its kind from which many goods are wont to follow, and worse from which many evils are wont to follow. In this doctrine, however, the general principle is supposed: for that goodness to be in fact contracted it must be intended; for malice to be contracted it must be in some way at least in a confused way foreseen, which nevertheless easily happens if the action is of itself apt to produce the bad effect.

3. The following event not pre-cogitated, if per accidens as in fewer cases follows, directly does not add to the goodness or malice, e. g., the abuse of alms by a poor man.

These things are to be understood, supposing that from the same act there does not follow as immediately a twofold effect: bad and good but greater and compensating. For then what was said n° 173 must be applied.

177. Corollary. — From what has been said it is understood, why and how far it is illicit voluntarily to expose oneself to the danger of doing evil or sinning: for this is not sufficiently to avoid the bad effect or even to place the cause of the bad effect. This danger, however, can be from an internal cause (such as evil imagination or passion) or external (i. e., occasion, such as a thing alluring to evil); — absolute, i. e., for all in common, or relative to such a determined person; — proximate or grave, which in many cases or more frequently is connected with sin, or remote or slight, which is rarely connected. Now:

1. It is illicit without a just and proportionate reason to expose oneself to a proximate or grave danger of doing evil. For he who without sufficient reason wills a thing, by that very fact imputably wills everything which is probably connected with it, and therefore he who intends to incur the danger of doing evil, by that very fact wills the evil probably connected with it. And he who is bound altogether to avoid sin, is also bound to avoid the means that probably leads to it. Whence he who does not avoid such danger, when he can, is convicted of not sufficiently avoiding it but of loving that evil, the danger of which he loves (Eccli. III, 27).

Hence everyone is bound under grave obligation to avoid a proximate grave danger of committing evil; under light obligation, a proximate light danger of committing evil.

2. It is lawful from a just proportionately grave reason, namely a compensating good effect, to expose oneself to even a grave and proximate danger of doing evil. The reason is that he who for a just reason exposes himself to danger, does not love the evil, but the good cause for which he so acts, nor properly exposes himself to danger but rather unwillingly undergoes the danger. Understand with this restriction: provided there is a founded hope of overcoming the danger and suitable precautions are employed by which the danger is made remote; for certain sin is absolutely to be avoided.

3. For a slight and remote danger (of some moment), even of committing grave evil, to expose oneself without a reason is illicit but lightly; but it is lawful for any reasonable, even slight, cause: for there is some disorder against reason in that someone, without cause, places a useless action, with which is also connected the danger of evil.