§ I. On Justice in General

I. Notion of Justice. Since justice of its own nature imports a certain rectitude of order, it can be taken in a broad sense, "according as the highest thing in man is subjected to God, and the lower powers of the soul are subjected, namely, to reason" (St. Thomas, I-II, q. 113, a. 1). In this sense justice is nothing other than the complex of all virtues and coincides with holiness. But justice is also taken in a less broad and in a strict sense.

Justice taken in a less broad sense is said of every moral virtue which is toward another and renders to him his right, whether taken more strictly or broadly; in this sense justice comprehends both justice strictly so called and its potential parts.

Justice taken in the strict sense is said of that moral virtue which renders to another a right taken in the stricter sense; and it is usually defined: a supernatural moral virtue inclining man to render to each one his own right (understand this as taken more strictly) (St. Thomas, II-II, q. 58, a. 1). It is said:

1. His own right. Here this is understood as a juridical debt which can be rendered according to equality.

a) A juridical debt, that is, a debt which someone must render to another because the other enjoys the power of exacting it, as a debt toward God, toward parents, or toward the seller of some thing.

It is distinguished from a moral debt, which someone must render to another from the moral goodness of virtue alone, without the other having the right to exact it. These debts do not pertain to justice properly so called, but to other virtues, for example gratitude and liberality.

b) Which can be rendered according to equality. Namely, among juridical debts some are so great that they cannot be paid according to equality, for example toward God (St. Thomas, II-II, q. 57, a. 1, ad 3) and parents. Nor do these debts pertain to justice properly so called, but to religion, piety, and observance. Other juridical debts are of such a kind that they can be rendered according to equality, for example the debt of a buyer toward a seller, likewise of a member toward a society or of a society toward a member. Now only these latter debts are spoken of in the definition given.

2. To each one, that is, to anyone who is at least morally another, as we shall soon explain more fully.

II. Object of Justice. 1. The material object is a thing, or an action or omission, owed to another according to equality; and in this indeed consists the remote material object of justice, while its proximate material object is formed by the very actions which the thing owed to another according to equality, whether to be preserved or to be restored, prescribes.

2. The remote formal object of justice is a thing owed to another according to equality, insofar as it is owed, or the very reason of debt; the proximate formal object is the special moral goodness shining forth in rendering the debt just explained.

III. Conditions Required for Justice. "The nature of justice consists in this, that there be rendered to another what is owed to him according to equality" (St. Thomas, II-II, q. 80, single article). From these words of the divine Thomas it follows that three conditions are required for justice, namely the condition of otherness, of debt, and of equality.

1. The condition of otherness. This condition is something specifically proper to the virtue of justice. For while the other cardinal virtues regard the internal acts of the agent himself, whether of the intellect, as prudence does, or of the will insofar as it is ordered to commanding the irascible sensitive appetite, as fortitude does, or of the will insofar as it is ordered to commanding the concupiscible sensitive appetite, as temperance does, justice by its nature has reference to another. But for this condition of otherness it suffices that the other person, although physically one, be virtually twofold: either by reason of office, as, for example, a creditor who at the same time is a guardian, for as creditor he can demand the debt from the ward, and as guardian in the ward's name render it back to himself; or by reason of a twofold nature, as in Christ, who as man made satisfaction for the sins of the human race to Himself as to another, namely considered under the divine nature.

2. The condition of debt, that is, of juridical debt, as was explained above, whether that debt arises from the title of a special destination of a thing for someone's advantage, or from a title inhering in the subject, for example one worthy to whom some good is granted, or from a title of jurisdiction.

3. The condition of equality, namely between the right which belongs to one and that by which this right is satisfied. Equality is distinguished as threefold, namely: 1. equality of thing to thing, specially destined for someone's advantage; it is called arithmetic and is regarded by commutative justice; 2. equality to be rendered, with the merit of the parties compared with one another being considered; it is usually called geometric, or of proportions, and is regarded by distributive justice; 3. equality to be rendered, with the necessity of the whole being considered; it is called equality of necessity and is regarded by legal justice.