2. But what if he foresees that a drug or treatment, which, he thinks, is needed for the mother's health, may perhaps bring on a miscarriage? Can he still administer that drug or prescribe that treatment? Notice the question carefully. It is not supposed that he wants to bring on the miscarriage. He does not; he will do all he can to prevent it. Nor will his treatment or drug directly destroy the life or the organism of the embryo; but it is intended to affect favorably the system of the mother, and it is applied to her own organism. Still the Doctor knows that the prescription may indirectly bring about abortion. Can he prescribe the drug or treatment from which he knows the death of the fœtus may indirectly result, the direct purpose being to remove an ailment of the mother's? There is a sound moral principle bearing on such cases; it is universally admitted in Ethics and Jurisprudence, and its application is so extensive that it well deserves careful study. It is this: "He who wilfully puts a cause is answerable for the effect of that cause," _causa causæ est causa causati_. Therefore, if the effect is evil, he is answerable for that evil. This, however, supposes that he could foresee the danger of such evil effect. That evil effect is said to be _indirectly_ willed; for it follows from a cause which is _directly_ willed. If, then, you should give a dose to a pregnant mother which is intended to stop her fever or other ailment, but may also bring on abortion, the stopping of her fever is directly intended, and the abortion is said to be indirectly intended or willed. Those are the received terms in moral science. It were more correct to say that the abortion in this case is an effect not intended at all, but only _permitted_. That, then, which is permitted to result from our acts is said to be indirectly willed. Are we then always responsible for evil effects permitted or indirectly willed? The principle laid down seems to say so. But then that principle admits of important exceptions. If we could never do an act from which we know evil consequences may follow, then we could scarcely do anything of importance; a young man could certainly not become a physician at all, for he is almost certain to injure some of his patients in the course of his professional life. But if we had no Doctors, such a loss would be a much greater evil to mankind than their occasional mistakes. Here then we seem to be in a dilemma, with evil on both sides of us. And then we are reminded of that other principle of which we spoke before, that we may never do evil at all that good may come of it. What shall we do? The solution is this: we should never _do_ evil, but we are often justified in _permitting_ evil to happen; in other words, we can never will evil _directly_, but we can often will it _indirectly_: we can do what is right in itself, even though we know or fear that evil will also result from our good act.