[60] CHAPTER V.

Who may lawfully make War.

I. AS in other things, so in the actions of the will, there are commonly three kinds of efficient causes; the principal, the auxiliary, and the instruments. The principal effective cause in war is commonly he whose interest is concerned; in private war, a private person; in public war, a public power, generally a sovereign power. Whether war may be made by another, for those who do not themselves stir in it, we shall see elsewhere. In the mean time we hold by this maxim; that by Natural Law, every one is the vindicator of his own right: this is what hands were given for.

II. 1 But further: to help another when we can, is not only lawful but proper. Those who have written of Duties, rightly say that nothing is so useful to man as other men. But there are various ties of men to men, which invite them to mutual aid. Relatives in blood unite for mutual help, and neighbours are called upon for aid, and fellow-citizens. Hence the Roman cry in sudden distress, Porro Quirites, et quiritari. Up Romans, for Romans. Aristotle says that every one ought to use arms for himself, if he has received an injury, or to help relatives, benefactors, allies who are injured. And Solon taught that a State was fortunate, in which every one thinks the injuries of others his own.

2 If other ties are wanting, the tie of a common human nature is sufficient. Nothing belonging to mankind is indifferent to man. So Menander, Democritus, Lactantius.

III. When we speak of Instruments, we do not here mean weapons or the like, but voluntary agents, whose will is moved by the will of another. Such an Instrument is a son to a father, a servant to a master: So Democritus. So a subject in a State is the instrument of the Ruler.

IV. By Natural Law all subjects may take part in war; but some are excluded by special law, as slaves formerly among the Romans, and clerical persons now. Which law, like all of that kind, is to be understood with an exception of extreme necessity.

And so much generally of auxiliaries and subjects: special considerations will be treated in their own place.