1. It is never lawful directly or indirectly to kill an innocent man. "Insontem et justum non occides" (Exod. xxiii. 7). An innocent man is one that has not by any human act done harm to another man or to society commensurate with the loss of his life. Directly means to kill either as an end, say, for revenge, or as a means toward an end.
A man is a person, an intelligent being, therefore free, and autocentric; he belongs to no one except to God, who made [{18}] him; he is by that very fact distinguished from brutes or things which may belong to another. Now, if you kill a man, you destroy his human nature by separating his soul and body, you subordinate and sacrifice him wholly to yourself, make him entirely yours, which is unjust. Even the state has no right to kill an innocent man. A foetus in the womb, only a few hours old, is as much a human being as a man fifty years of age, and this natural law holds for the foetus as for the man.
2. It is, however, lawful indirectly to kill a man provided this man is an unjust aggressor. Cardinal de Lugo (De Just. et Jure, 10, 149) and others hold you may even directly kill an unjust aggressor. Indirectly here means incidentally. An effect happens indirectly when it is neither intended as an end nor a means, but happens as a circumstance unavoidably attached to the end or means intended.
We may not, however, kill an innocent man even indirectly, because no end is proportionate to the sacrifice of an innocent man's life, but the case of an unjust aggressor differs from that of an innocent man. By an unjust aggressor is meant some one that outside the due course of law threatens your life or the equivalent of your life, or the life of some one you should or may protect. You may stop such an aggressor, and if you happen to kill him while trying to stop him, there is no moral wrong involved. This aggressor may be formally or only materially unjust: he may be a normal man with a formal intention to kill you or your ward, or a murderous lunatic that tries to kill you or your ward, but he must be unjust either formally or materially.
It is natural for every being to maintain itself in existence, to resist destruction. This is a primary law of nature. As Father Holaind well said (Amer. Eccl. Rev., January, 1894): "The ethical foundation of self-defence is this: Justice requires a sort of moral equation, and if a right prevails it must be superior to the right which it holds in abeyance. At the outset both the aggressor and his intended victim have equal rights to life, but the fact of the former using his own life for the destruction of a fellow man places him in a condition of juridic inferiority with regard to the latter. If we may be [{19}] allowed so to express it, the moral power of the aggressor is equal to his inborn right to life, less the unrighteous use which he makes of it, whilst the moral power of the intended victim remains in its integrity and has consequently a higher juridic value. When the person assailed cannot defend himself, his right can and sometimes must be exercised by those who are bound in justice or charity to protect the innocent. At the dawn of human life the physician or surgeon stands as the natural protector both of the mother and of the child; he is beholden to both.
"The right of self-defence is not annulled by the fact that the aggressor is irresponsible. The absence of knowledge saves him from moral guilt, but it does not alter the character of the act, considered objectively and in itself; it is yet an unjust aggression, and in the conflict, the life assailed has yet a superior juridic value. The right of killing in self-defence is not based on the ill will of the aggressor but on the illegitimate character of the aggression. Now, an aggressor is at least materially unjust whenever he perpetrates an act destructive of the right of another."
Mark the words "right of another," at the end of the quotation. In a case of pregnancy at term in a woman with a contracted pelvis the foetus would be a contributing instrument of death to the mother, supposing there were no artificial means of delivering her, but such a child is not an aggressor even materially unjust. The child itself is normal, it has a natural right to be where it is, it did not put itself where it is; the mother's contracting uterus crushing the child against her narrow pelvic arch is the direct agency that kills the woman, and the child is only an inert instrument used by the contracting uterus. In such a case the mother might be considered an aggressor materially unjust against the life of the child rather than that the child is the aggressor.
Lehmkuhl (Compendium Theologiae Moralis, 1891, p. 238) says: "Medicus graviter peccat … si media abortus procurat: nisi quando ad salvandam matrem ex probabili opinione liceat." On page 188 he says: "Ex consulto abortum inducere, etiam liceri videtur in praesenti vitae [{20}] maternae discrimine, quod per solam foetus immaturi ejectionem avert! possit … Idque videtur applicari posse ad matrem quae tarn arcta est ut tempus praematuri partus exspectare non possit."
By foetus immaturus here he means an unviable foetus, as is evident from the context. If this probabilism of Father Lehmkuhl's stands (but it does not), a decision in most of the cases that occur in ectopic gestation would be easily made, but even he himself would not take responsibility in the matter, and that before the decision of the Holy Office which defined abortion. Since this decision, made July 24, 1895, Lehmkuhl has entirely withdrawn his opinion.
On May 4, 1898, the Holy Office published the following decree, which was approved by the Pope:
BEATISSIME PATER,—Episcopus Sinaloen. ad pedes S. V. provolutus, humiliter petit resolutionem insequentium dubiorum:
I. Eritne licita partus acceleratio quoties ex mulieris arctitudine impossibilis evaderet foetus egressio suo naturali tempore?
II. Et si mulieris arctitudo talis sit, ut neque partus prematurus possibilis censeatur, licebitne abortum provocare aut caesariam suo tempore perficere operationem?
III. Estne licita laparotomia quando agitur de pregnatione extra-uterina, seu de ectopicis conceptibus?
Feria iv, die 4 Mali, 1898.
In Congregatione habita, etc … EE. ac RR. Patres rescribendum censuerunt:
Ad I. Partus accelerationem per se illicitam non esse, duromodo perficiatur justis de causis et eo tempore ac modis, quibus ex ordinariis contingentibus matris et foetus vitae consulatur.
Ad II. Quoad primam partem, negative, juxta decretum, Feria iv., 24 Julii, 1895, de abortus illiceitate.—Ad secundam vero quod spectat: nihil obstare quominus mulier de qua agitur caesareae operationi suo tempore subjiciatur.
Ad III. Necessitate cogente, licitam esse laparotomiam ad extra-hendos e sinu matris ectopicos conceptos, dummodo et foetus et matris vitae, quantum fieri potest, serio et opportune provideatur.
In sequenti Feria vi., die 6 ejusdem mensis et anni … SSmus responsiones EE. ac RR. Patrum approbavit.