XXVI.23 That when, by some circumstance, the political law destroys the state, one must decide by the political law that preserves it, which sometimes becomes a law of nations
When the political law which has established a certain order of succession in the state becomes destructive of the political body for which was made, there can be no doubt that another political law could change that order ; and far from that same law being opposed to the first, it will fundamentally be perfectly compatible with it, since they will both depend on the principle that the safety of the people is the supreme law. [1]
I have said [2] that a great state that had become accessory to another weakened itself, and even weakened the principal state. We know that it is in the state’s interest to have its chief at home, for the public revenues to be well administered, for its money not to go enrich another country. It is important that he who is to govern not be imbued with foreign maxims : they are less apposite than the ones already established ; besides, men hold fiercely to their laws and customs ; in them lies the felicity of each nation ; it is rare that they are changed without great upheavals and a great effusion of blood, as the histories of all countries show.
It follows from this that if the heir of a great state is the possessor of a great state, the former can very well exclude him, because it serves both states for the order of succession to be changed. Thus does the law of Russia made early in the reign of Elisabeth very prudently exclude any heir who possesses another monarchy ; thus does the law of Portugal reject any foreigner called to the crown by right of blood.
Now if a nation can exclude, it has a fortiori the right to compel a renunciation. If it fears lest a certain marriage have consequences that can cause it to lose its independence or force it to a division, it may very well compel the contracting parties with their descendants to renounce all the rights they would have to it ; and he who renounces, and those against whom he renounces, will be all the less entitled to complain because the state could have made a law excluding them.