Secondly, Though the accession of the Prince of Orange to the throne might at first give occasion to many disputes, and his title be contested, it ought not now to appear doubtful, but must have acquired a sufficient authority from those three princes, who have succeeded him upon the same title.  Nothing is more usual, though nothing may, at first sight, appear more unreasonable, than this way of thinking.  Princes often seem to acquire a right from their successors, as well as from their ancestors; and a king, who during his life-time might justly be deemed an usurper, will be regarded by posterity as a lawful prince, because he has had the good fortune to settle his family on the throne, and entirely change the antient form of government.  Julius Caesar is regarded as the first Roman emperor; while Sylla and Marius, whose titles were really the same as his, are treated as tyrants and usurpers.  Time and custom give authority to all forms of government, and all successions of princes; and that power, which at first was founded only on injustice and violence, becomes in time legal and obligatory.  Nor does the mind rest there; but returning back upon its footsteps, transfers to their predecessors and ancestors that right, which it naturally ascribes to the posterity, as being related together, and united in the imagination.  The present king of France makes Hugh Capet a more lawful prince than Cromwell; as the established liberty of the Dutch is no inconsiderable apology for their obstinate resistance to Philip the second.

SECT.  XI OF THE LAWS OF NATIONS

When civil government has been established over the greatest part of mankind, and different societies have been formed contiguous to each other, there arises a new set of duties among the neighbouring states, suitable to the nature of that commerce, which they carry on with each other.  Political writers tell us, that in every kind of intercourse, a body politic is to be considered as one person; and indeed this assertion is so far just, that different nations, as well as private persons, require mutual assistance; at the same time that their selfishness and ambition are perpetual sources of war and discord.  But though nations in this particular resemble individuals, yet as they are very different in other respects, no wonder they regulate themselves by different maxims, and give rise to a new set of rules, which we call the laws of nations.  Under this head we may comprize the sacredness of the persons of ambassadors, the declaration of war, the abstaining from poisoned arms, with other duties of that kind, which are evidently calculated for the commerce, that is peculiar to different societies.