Analysis of the moral act. A proposal
II.d.5. The action of double effect
Classical moral studies, following St. Thomas’ systemization in the Summa Theologiae (83), analyze in the moral act the object, end and circumstances. In order to examine the licitness of actions which have both good and bad effects, these three elements are not enough. They have to recur to an elaboration of rules which will permit us to determine whether an action with both good and bad effects can be carried out without moral culpability. These rules constitute what is called the principle of the action of double effect.
Its formulation varies from author to author. One of the variations, previously mentioned, describes the principle in the following terms: a) the action in itself is good or indifferent; b) the evil consequence does not follow as a direct result of the action carried out; c) the action was carried out to attain a good end; d) there exists proportionality between the good and bad effects.
If we examine these rules from the point of view we have been employing up until now, we will observe that these rules, correctly understood and for all practical effects, are simply another way of formulating what we have been saying all along. Thus rule (a) is the equivalent of saying that the decision-action must be good or indifferent, as we have previously affirmed. Rule (b) tries to exclude the bad consequence’s being a means for the intended end; if this bad consequence were a means, it would flow more proximately from the action than would the end, and thus by this rule the possibility of doing evil to achieve good is eliminated. As the means are intermediate ends, object of the intention of the acting subject, this rule finds itself included in the obligation that the intention be good. Rule (c) is equivalent to saying directly that the intention must be good. And rule (d) is equivalent to what St. Thomas affirmed with respect to tolerated effects: they must maintain a proportion to what is being intended, given that what is intended is, in addition to object of the intention, an effect of the action.
Other formulations of the principle of the action of double effect can also redirect us without special difficulties to the Thomistic principles we have set forth, although for the sake of brevity we will omit additional examples. We thus reach the conclusion that if instead of examining within an action only the object, the end and the circumstances, we examine the intention, the decision-action and the proportion of effects that are tolerated in addition to what is intended, the rules of the principle of the action of double effect become superfluous, because they are perfectly included and integrated in the focus of the moral act that we have been stating explicitly, and are more ample and profound from the theoretical point of view than what is normally managed.