Thomas Aquinas, Summa Theologiae

Objection 1: It would seem that in no case can it be lawful to maim anyone. For Damascene says (De Fide Orth. iv, 20) that "sin consists in departing from what is according to nature, towards that which is contrary to nature." Now according to nature it is appointed by God that a man's body should be entire in its members, and it is contrary to nature that it should be deprived of a member. Therefore it seems that it is always a sin to maim a person.

Objection 2: Further, as the whole soul is to the whole body, so are the parts of the soul to the parts of the body (De Anima ii, 1). But it is unlawful to deprive a man of his soul by killing him, except by public authority. Therefore neither is it lawful to maim anyone, except perhaps by public authority.

Objection 3: Further, the welfare of the soul is to be preferred to the welfare of the body. Now it is not lawful for a man to maim himself for the sake of the soul's welfare: since the council of Nicea punished those who castrated themselves that they might preserve chastity. Therefore it is not lawful for any other reason to maim a person.

On the contrary, It is written (Ex. 21:24): "Eye for eye, tooth for tooth, hand for hand, foot for foot."

I answer that, Since a member is part of the whole human body, it is for the sake of the whole, as the imperfect for the perfect. Hence a member of the human body is to be disposed of according as it is expedient for the body. Now a member of the human body is of itself useful to the good of the whole body, yet, accidentally it may happen to be hurtful, as when a decayed member is a source of corruption to the whole body. Accordingly so long as a member is healthy and retains its natural disposition, it cannot be cut off without injury to the whole body. But as the whole of man is directed as to his end to the whole of the community of which he is a part, as stated above (Question 61, Article 1; Question 64, Articles 2,5), it may happen that although the removal of a member may be detrimental to the whole body, it may nevertheless be directed to the good of the community, in so far as it is applied to a person as a punishment for the purpose of restraining sin. Hence just as by public authority a person is lawfully deprived of life altogether on account of certain more heinous sins, so is he deprived of a member on account of certain lesser sins. But this is not lawful for a private individual, even with the consent of the owner of the member, because this would involve an injury to the community, to whom the man and all his parts belong. If, however, the member be decayed and therefore a source of corruption to the whole body, then it is lawful with the consent of the owner of the member, to cut away the member for the welfare of the whole body, since each one is entrusted with the care of his own welfare. The same applies if it be done with the consent of the person whose business it is to care for the welfare of the person who has a decayed member: otherwise it is altogether unlawful to maim anyone.

Reply to Objection 1: Nothing prevents that which is contrary to a particular nature from being in harmony with universal nature: thus death and corruption, in the physical order, are contrary to the particular nature of the thing corrupted, although they are in keeping with universal nature. In like manner to maim anyone, though contrary to the particular nature of the body of the person maimed, is nevertheless in keeping with natural reason in relation to the common good.

Reply to Objection 2: The life of the entire man is not directed to something belonging to man; on the contrary whatever belongs to man is directed to his life. Hence in no case does it pertain to a person to take anyone's life, except to the public authority to whom is entrusted the procuring of the common good. But the removal of a member can be directed to the good of one man, and consequently in certain cases can pertain to him.

Reply to Objection 3: A member should not be removed for the sake of the bodily health of the whole, unless otherwise nothing can be done to further the good of the whole. Now it is always possible to further one's spiritual welfare otherwise than by cutting off a member, because sin is always subject to the will: and consequently in no case is it allowable to maim oneself, even to avoid any sin whatever. Hence Chrysostom, in his exposition on Mt. 19:12 (Hom. lxii in Matth.), "There are eunuchs who have made themselves eunuchs for the kingdom of heaven," says: "Not by maiming themselves, but by destroying evil thoughts, for a man is accursed who maims himself, since they are murderers who do such things." And further on he says: "Nor is lust tamed thereby, on the contrary it becomes more importunate, for the seed springs in us from other sources, and chiefly from an incontinent purpose and a careless mind: and temptation is curbed not so much by cutting off a member as by curbing one's thoughts."

Articulus 1

Argumentum 1

Ad primum sic proceditur. Videtur quod mutilare aliquem membro in nullo casu possit esse licitum.

Damascenus enim dicit, in II libro, quod peccatum committitur per hoc quod receditur ab eo quod est secundum naturam in id quod est contra naturam.

Sed secundum naturam a deo institutam est quod corpus hominis sit integrum membris; contra naturam autem est quod sit membro diminutum. Ergo mutilare aliquem membro semper videtur esse peccatum.

Argumentum 2

Praeterea, sicut se habet tota anima ad totum corpus, ita se habent partes animae ad partes corporis, ut dicitur in II de anima.

Sed non licet aliquem privare anima occidendo ipsum, nisi publica potestate. Ergo etiam non licet aliquem mutilare membro, nisi forte secundum publicam potestatem.

Argumentum 3

Praeterea, salus animae praeferenda est saluti corporali.

Sed non licet aliquem mutilare se membro propter salutem animae, puniuntur enim secundum statuta nicaeni Concilii qui se castraverunt propter castitatem servandam.

Ergo propter nullam aliam causam licet aliquem membro mutilare.

Sed Contra

Sed contra est quod dicitur Exod. XXI, oculum pro oculo, dentem pro dente, manum pro manu, pedem pro pede.

Corpus

Respondeo dicendum quod cum membrum aliquod sit pars totius humani corporis, est propter totum, sicut imperfectum propter perfectum. Unde disponendum est de membro humani corporis secundum quod expedit toti. Membrum autem humani corporis per se quidem utile est ad bonum totius corporis, per accidens tamen potest contingere quod sit nocivum, puta cum membrum putridum est totius corporis corruptivum. Si ergo membrum sanum fuerit et in sua naturali dispositione consistens, non potest praecidi absque totius hominis detrimento. Sed quia ipse totus homo ordinatur ut ad finem ad totam communitatem cuius est pars, ut supra dictum est; potest contingere quod abscisio membri, etsi vergat in detrimentum totius corporis, ordinatur tamen ad bonum communitatis, inquantum alicui infertur in poenam ad cohibitionem peccatorum. Et ideo sicut per publicam potestatem aliquis licite privatur totaliter vita propter aliquas maiores culpas, ita etiam privatur membro propter aliquas culpas minores. Hoc autem non est licitum alicui privatae personae, etiam volente illo cuius est membrum, quia per hoc fit iniuria communitati, cuius est ipse homo et omnes partes eius. Si vero membrum propter putredinem sit totius corporis corruptivum, tunc licitum est, de voluntate eius cuius est membrum, putridum membrum praescindere propter salutem totius corporis, quia unicuique commissa est cura propriae salutis. Et eadem ratio est si fiat voluntate eius ad quem pertinet curare de salute eius qui habet membrum corruptum.

Aliter autem aliquem membro mutilare est omnino illicitum.

Ad 1

Ad primum ergo dicendum quod nihil prohibet id quod est contra particularem naturam esse secundum naturam universalem, sicut mors et corruptio in rebus naturalibus est contra particularem naturam eius quod corrumpitur, cum tamen sit secundum naturam universalem. Et similiter mutilare aliquem membro, etsi sit contra naturam particularem corporis eius qui mutilatur, est tamen secundum naturalem rationem in comparatione ad bonum commune.

Ad 2

Ad secundum dicendum quod totius hominis vita non ordinatur ad aliquid proprium ipsius hominis, sed ad ipsam potius omnia quae sunt hominis ordinantur. Et ideo privare aliquem vita in nullo casu pertinet ad aliquem nisi ad publicam potestatem, cui committitur procuratio boni communis. Sed praecisio membri potest ordinari ad propriam salutem unius hominis.

Et ideo in aliquo casu potest ad ipsum pertinere.

Ad 3

Ad tertium dicendum quod membrum non est praecidendum propter corporalem salutem totius nisi quando aliter toti subveniri non potest. Saluti autem spirituali semper potest aliter subveniri quam per membri praecisionem, quia peccatum subiacet voluntati. Et ideo in nullo casu licet membrum praecidere propter quodcumque peccatum vitandum.

Unde chrysostomus, exponens illud Matth. XIX, sunt eunuchi qui seipsos castraverunt propter regnum caelorum, dicit, non membrorum abscisionem, sed malarum cogitationum interemptionem. Maledictioni enim est obnoxius qui membrum abscidit, etenim quae homicidarum sunt talis praesumit.

Et postea subdit, neque concupiscentia mansuetior ita fit, sed molestior. Aliunde enim habet fontes sperma quod in nobis est, et praecipue a proposito incontinenti et mente negligente, nec ita abscisio membri comprimit tentationes, ut cogitationis frenum.