17. Also what cannot be divided nor had in common, it is provided by the law of nature, which may be the twelfth precept, that the use of that thing be either by turns, or adjudged to one only by lot; and that in the using it by turns, it be also decided by lot, who shall have the first use of it. For here also regard is to be had unto equality: but no other can be found but that of lot.
The thirteenth law, of birthright and first possession.
18. But all lot is twofold, arbitrary or natural.
Arbitrary is that which is cast by the consent of the contenders, and it consists in mere chance, as they say, or fortune. Natural is primogeniture, in Greek κληρονομια, as it were, given by lot; or first possession. Therefore the things which can neither be divided nor had in common, must be granted to the first possessor; as also those things which belonged to the father are due to the son, unless the father himself have formerly conveyed away that right to some other. Let this therefore stand for the thirteenth law of nature.
The fourteenth law, of the safety of those who are mediators for peace.
19. The fourteenth precept of the law of nature is, that safety must be assured to the mediators for peace. For the reason which commands the end, commands also the means necessary to the end. But the first dictate of reason is peace; all the rest are means to obtain it, and without which peace cannot be had. But neither can peace be had without mediation, nor mediation without safety. It is therefore a dictate of reason, that is, a law of nature, that we must give all security to the mediators for peace.
The fifteenth law, of appointing an umpire.
20. Furthermore because, although men should agree to make all these and whatsoever other laws of nature, and should endeavour to keep them, yet doubts and controversies would daily arise concerning the application of them unto their actions, to wit, whether what was done were against the law or not, which we call the question of right; whence will follow a fight between parties, either-sides supposing themselves wronged: it is therefore necessary to the preservation of peace, because in this case no other fit remedy can possibly be thought on, that both the disagreeing parties refer the matter unto some third, and oblige themselves by mutual compacts to stand to his judgment in deciding the controversy. And he to whom they thus refer themselves, is called an arbiter. It is therefore the fifteenth precept of the natural law, that both parties disputing concerning the matter of right, submit themselves unto the opinion and judgment of some third.
The sixteenth law, that no man be judge in his own cause.
21. But from this ground, that an arbiter or judge is chosen by the differing parties to determine the controversy, we gather that the arbiter must not be one of the parties. For every man is presumed to seek what is good for himself naturally, and what is just only for peace sake and accidentally; and therefore cannot observe that same equality commanded by the law of nature, so exactly as a third man would do. It is therefore in the sixteenth place contained in the law of nature, that no man must be judge or arbiter in his own cause.