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islative authority, and to distinguish between those commands which fall within the boundaries prescribed and those which do not.
Let us consider the first of these cases. If the sovereign's power to make laws can be limited to a certain class of affairs, it is clear that other matters not within these limits may form the sphere of action of another sovereign, and thus two sovereigns may issue commands to the same subjects, each being supreme in his own department. It may not, perhaps, be always easy in such cases to define accurately the boundaries of each ruler's authority ; but this difficulty, which arises from the impossibility of an exact classifica- tion of all human actions, is constantly met with in applying the law, and does not affect the proposition that two sovereigns with different spheres of activity may govern the same subjects. The relation of the Church to the various temporal rulers in Europe during the Middle Ages was, indeed, of the character here de- scribed.
The possibility of what I may call a dual sovereignty in one political society suggests an inquiry into the connection between the terms " sovereign " and " nation." The former is the name given to an independent political superior, considered in relation to his subjects. The latter is applied to the society composed of the superior and the subjects, considered in relation to other independent political societies. Now, it is often assumed that these two conceptions are inseparable; that every nation must have one and only one sovereign, and that every sovereign, together with his subjects, must constitute a nation; but I think that this is a mistake, because, if, as I have urged, there can exist within the same ter- ritory two sovereigns, issuing commands to the same subjects touching different matters, it may very well happen that one of them has no relations with other independent political societies. It may happen, for example, that the authority of a sovereign, in respect to the matters within his competence, extends over several communities, each of which is subject in other matters to an inde- pendent political superior of its own, while all the relations with foreign powers fall within the competence of the central govern- ment, and in this case the lesser political bodies, although strictly sovereign, could not properly be called nations. I do not assert that this is true of the United States, but merely that there is nothing illogical or impossible in such a state of things. The proposition in fact, that a nation can have only one sovereign, and