Question III. What seizures of prize or booty are just?
Question IV. What wars are just? [26]
Conclusion III.
Based upon Gen. Exp. of Qu. II
Granting, then, that there are certain cases in which the seizure of prize or booty should be characterized as just, we have still to ascertain what cases come under that head. This problem does not call for prolonged consideration, since the foregoing discussion clearly shows that all seizures of prize or booty are just, which result from a just war.a That is the universally accepted conclusion.
The entire argument now turns upon the question, “What wars are just?”b
First of all, we must clear away the ambiguity attached to the term iustus [just, proper, perfect, &c.]. For when I use this term I do not have in mind the sense in which it is sometimes employed, connoting full attainment of inherent potentialities (as in the expressions iusta aetas [a proper age], iustum navigium [a perfect boat], iustum opus [a perfect work]), nor do I refer to the acquisition of certain formal external attributes (the concept underlying the phrase iusta materfamilias [a perfect materfamilias]). To be sure, these connotations do enter into the question under consideration, since the expression iustum bellum [a just or proper war] is used in both of the above-mentioned senses by writers on the subject. Nevertheless, I am employing the word iustus exclusively to denote that which lacks none of the qualifications required by any law, human or divine.
Now, these qualifications have been discussed by the different authorities in varying and rather disorderly fashion. Certain writersa have listed seven names, rather than seven kinds, of war. Moreover, their list is not complete, nor are the items included therein sufficiently distinct from one another. Other writers have maintained that a just war must be directed by a [competent] judge and in accordance with law. Still others,b dealing with this same point, inquire into the authority behind the war, its cause (their term for its origin) and the accompanying intention (or rather, the purpose of the various participants). There are some whose inquiries relate to “cause,” “mode,” and “necessity.” Yet another groupc contributing to this discussion, contend that the war should be necessary to such a degree as to be avoidable only at the cost of imperilling the state, and that it should be waged by command of the supreme magistrate, for a just cause, after formal declaration and notice to the enemy. There are some authorities,d too, who discuss the problem under these heads: “subject-matter of the dispute,” “cause,” “intent,” “authority,” and “persons engaged.”
New explanation
The defects or superfluous aspects of each of the classifications mentioned will become apparent, however, if we analyse war on the basis of four types of cause.e For actions, no less than other matters, are customarily explained on this fourfold basis. Indeed, the faultiness of any of the causes underlying an action will suffice to render that action faulty;f whereas, in order that the action may be righteous, it is necessary [26′] that all of those causes should exist concurrently in the proper form, since righteousness, of course, must conform to a single standard. This distinction is pointed out in the Greek saying,a
ἐσθλοὶ μὲν γὰρ ἁπλω̑ς παντοδαπω̑ς δὲ κακοί.
Goodness wears a single form, but evil is multiform.
Conclusion IV
We conclude, therefore, that every war derived entirely from just causes, is a just war.
Consequently, it is necessary to investigate the subject of causes. We must ascertain, first, what persons justly wage war; secondly, on what grounds and against whom they do so; thirdly, in what manner—that is to say, within what limits—war is so waged, and fourthly, to what end and with what intent this is done.
It should be observed, moreover, that we have not undertaken this task because we disapprove of the work done in connexion with the law of war by other investigators, whose authority, as a matter of fact, will prove very helpful to us. We are motivated rather by the belief that, with the aid of the additional material so far gathered by us, we shall be able to make some further contribution to the accuracy, or at least to the clear and orderly arrangement, of the doctrines handed down by those earlier investigators.
Concerning the Efficient Cause of War
Article I. What is a just efficient cause of private war?
Article II. What is a just efficient cause of public war?
We are told that some of the causes effecting a given result are principal causes, while others are contributory and still others are to be classified as instrumental. Certainly all three kinds of cause are discernible in connexion with voluntary human actions (among which war is included), just as they are in regard to most other things.
In the natural order, as we have already pointed out, every individual is charged with the execution of his own rights. For we have been compounded of mind and body with precisely this purpose in view, namely, that the body may be the servant of the mind.a This very point is borne out by the uses of our bodily members, and particularly by the uses assigned to the hands,b since we defend ourselves by thrusting the hands forward, and claim a thing as our own by laying our hands upon it. [27]
It is also natural for us to do good to one another, and to lend each other aid.c For it is right that we should accord to others the same treatment that we wish to receive when we ourselves are in distress.d It has been well said by those writersa who discuss the subject of duties that, in accordance with God’s Will, nothing—save God Himself—should be more useful to man than his fellow man. Moreover, human beings employ certain terms denoting fellowship; and in obedience to the implications thereof, kinsmen unite for mutual aid, neighbours are called upon in time of needb and all the citizens of a given community are likewise invoked as a whole,c whence there has arisen that well-known line employed on the stage, “Forward, Roman citizens!”d Thus Solon (so we are told) laid down the doctrine that the state wherein each individual regards injuries to others as injuries to himself, will be a happy state. Democrituse has said: ἀδικουμἑνοισι τιμωρει̑ν κατὰ δύναμιν χρὴ καὶ μὴ παριἑναι. τὸ μὲν γὰρ τοιου̑το δίκαιον καὶ ἀγαθόν, τὸ δὲ μὴ τοιου̑τον ἄδικον καὶ κακόν. “It behoves us to defend with all our might the victims of unjust oppression, and not to leave them neglected; for the former course is just and good, whereas the latter is unjust and wicked.” In the works of Aristotle,f too, we find this excellent passage: δει̑ τοὺς ἀδικουμἑνους ὑπὲρ ἑαυτω̑ν