Summa summae S. Thomae, Tomus III

(D. Thomas, IIae IIae, q. 58.)

Justice is taken in two ways : 1° generally for Christian holiness or for the collection of all the virtues, in which sense Christ said, Matt., V, 20 : Unless your justice abound more than that of the Scribes and Pharisees, etc. 2° It is taken specially for the particular virtue which is second among the Cardinal virtues, by which one is inclined to render to everyone what is his, and of that we treat here.

Justice is defined in law, from Ulpian : « The constant and perpetual will to render to each his right. »

By will is not understood the very power of willing, but the act¹ ; whence a habit is defined through the act : which is not unusual. It is called « perpetual », not on the part of the act, which endures perpetually, but on the part of the object, insofar as the just man wills to render to everyone his right perpetually and in all things : whence, if anyone wishes to reduce this definition to due form, let him say that justice is « the virtue inclining the will constantly to render forever to everyone his right ». Hence you have that it belongs to the reason of justice properly so called that it be toward another.

I say 2°: The remote material object of justice are external things which are commuted or distributed. The proximate material object are the actions by which these things are commuted and distributed. Because justice differs in this from the other moral virtues, that these rectify primarily and per se man in himself, but justice in order to another². Now the ordination of one man to another is not attended to according to interior affections or passions, but according to exterior actions and things by which men can communicate with one another, such as, as to things, goods of fortune, money, houses, fields, grains, etc. ; as to actions, those by which these things are commuted, namely sale, payment, loan for consumption, loan for use, lease, etc. ; likewise also those actions in which no exterior thing intervenes, as honor, praise, detraction, etc. Therefore.

The formal object quod of justice is right taken for the just, or the equal owed to another³ ; because this justice principally intends and effects, as appears from its definition, and thereby it is distinguished from the other virtues. Whence he is called just who makes or preserves this equality, unjust who does not preserve it.

The formal object quo is the ratio of debt, or right in another, taken for the legitimate faculty of possessing, alienating, etc. For the reason why I render the equal to another is because I owe it to him ; I owe it however because that other has a right to it : for debt and right are correlatives.

I say 3°: The subject of justice is the will⁴. For it is not the intellect, because justice is not ordered per se and primarily to direct any cognitive act ; nor is it the sensitive appetite, because the sensitive appetite follows sensitive apprehension, but sensitive apprehension does not consider the proportion of one thing to another, which pertains to justice ; for this is proper to reason. Therefore.

Justice, as such, is divided into general or legal, by which it orders citizens to the general or common good, as parts to the whole, and particular, which orders citizen to citizen¹.

I say 2°: Particular justice is adequately subdivided into commutative and distributive, as into essentially distinct species²

Proof. first part³. Particular justice is the virtue by which one is ordered to some particular person. Now the order of one to another particular is twofold, namely either of part to part, or of whole to part. The first commutative justice directs, the second distributive. Therefore.

Proof. second part⁴. 1° Since it pertains to the reason of justice that one render what is owed to another, where there is found a special reason of debt to some person, there is a special virtue. Now in commutative and distributive justice a special reason of debt is found. Therefore. — Proof. of the minor. In commutative justice there is rendered to each what is his and simply owed, namely what is proper and appropriated to him and within his dominion, although held by another. In distributive justice truly there is rendered to each what is his and owed, not simply, but secundum quid, by the right namely of condignity and of the community of which he is a part ; for the things of the whole are, in a certain way, the things of the parts. Now this reason of debt is diverse, as is plain. For in one way is owed the thing which is the creditor's own and already committed to his dominion ; in another because it belongs to the whole community of which he is a member, and for that reason, his condignity being considered, he has the right that it become his own. Therefore.

Nota. And this is the reason why violation of commutative justice induces the obligation of restitution, not violation of distributive justice precisely qua such.

Proof. 2°. The general form of justice is equality⁵. Now a diverse equality is found in commutative and distributive justice. Therefore. — Proof. of the minor. In commutative justice there is an absolute equality of thing to thing, which is called arithmetical proportion, as if you owe a hundred, you render a hundred ; in distributive there is an equality not absolute, but of proportion, which is called geometrical, as if, v. g., in the distribution of the common good ten coins be given to him who has six degrees of merit, five be given to him who has three degrees. Therefore.

You will ask whether between father and son not emancipated, between master and slave, between husband and wife there is justice properly so called.

I answer. There is justice properly so called, yet not altogether perfect⁶ ; because, although the son, as son, is something of the father, as a part of him, the slave something of the master, as his instrument, the wife something of the husband, who is her head and to whom she is subject, from which aspect there is not between them perfect justice toward another : nevertheless, insofar as these men are distinct supposita, the son from the father, the slave from the master, the wife from the husband ; justice under that aspect is toward another, and thus the reason of justice properly so called is saved, though not altogether perfect.