20 ARGUMENT OF THE UNITED STATES. 



as the different kinds of acquisition, contracts, and other similar things, 

 either belong to the natural law or form part of the civil law of every 

 nation. And, although in regard to those things which are not based 

 upon the universal constitution of the human race, the laws are the same 

 among the majority of the nations, no particular kind of law results from 

 this, for it is not in virtue of any agreement or of any mutual obliga- 

 tion that these laws are common to several peoples, but purely and 

 simply from an effect of the particular will of the legislators of each 

 State, who have by chance agreed in ordering or forbidding the same 

 things. Hence it is that a single people can change these laws of its 

 own accord without consulting others, as has frequently been done. 



We must not, however, absolutely reject the opinion of a modern 

 writer, who claims that the Roman jurisconsults -understand by law of 

 nations that law which concerns those acts which foreigners could per- 

 form, and the business which they could validly transact in the states 

 belonging to the Roman people, in contrast with the civil law that was 

 particular to Roman citizens. Hence it was that wills and marriages, 

 which were valid among citizens only were referred to civil law, while 

 contracts were considered as coming under the law of nations, because 

 foreigners could make them with citizens in such a manner that they 

 were valid before the Roman courts of justice. Many also apply the 

 name law of nations to certain customs, especially in matters relating 

 to war, which are usually practiced by a kind of tacit consent, among 

 the majority of nations, at least among those that pride themselves on 

 having some courtesy and humanity. 



In fact, inasmuch as civilized nations have attached the highest glory 

 to distinction in war; that is to say, to daring and knowing how skill- 

 fully to cause the death of a large number of persons, which has in all 

 ages given rise to many unnecessary or even unjust wars, conquerors, 

 in order not to render themselves wholly odious by their ambition, 

 have thought proper, while claiming every right that one has in a just 

 war— have thought proper, I say, to mitigate the horrors of war and of 

 military expeditions by some appearance of humanity and magna- 

 nimity. Hence the usage of sparing certain kinds of things and cer- 

 tain classes of persons, of observing some moderation in acts of hos- 

 tility, of treating prisoners in a certain way, and other similar things. 

 Yet while such customs seem to involve some obligation, based at 

 least upon a tacit agreement, if a prince in a just war fails to observe 

 them, provided that by taking an opposite course he does not violate 

 natural law, he can be accused of nothing more than a kind of dis- 

 courtesy, in that he has not observed the received usage of those 

 who regard war as being one of the liberal arts; just as among fencing 

 masters, one who has not wounded his man according to the rules of 

 art is regarded as an ignorant person. 



Thus, so long as none but just wars are carried on, the maxims of 

 natural law alone may be consulted, and all the customs of other nations 

 maybe set at naught unless one is interested in conforming thereto, so 

 as to induce the enemy to perform less rigorous nets of hostility against 

 us and against our party. Those, however, who undertake an unjust 

 war, do well to follow these customs, so as to maintain at least some 

 moderation in their injustice. As, however, these are not reasons that 

 are generally to be considered, they can constitute no universal law, 

 obligatory upon all nations; especially since in all things that are only 

 based upon tacit consent anyone may decline to be bound by them by 

 expressly declaring that he will not be so bound, and that he is willing 

 that others should not be thereby bound in their dealings with him. 



