For one thing, the association of ideas involved in the two sets of relations—the physical and the mental on the one hand, and the purely legal on the other—is in the very nature of the case, extremely close. This fact has necessarily had a marked influence upon the general doctrines and the specific rules of early systems of law. Thus, we are told by Pollock and Maitland:
Ancient German law, like ancient Roman law, sees great difficulties in the way of an assignment of a debt or other benefit of a contract * * * men do not see how there can be a transfer of a right unless that right is embodied in some corporeal thing. The history of the incorporeal things has shown us this; they are not completely transferred until the transferee has obtained seisin. has turned his beasts onto the pasture, presented a clerk to the church or hanged a thief upon the gallows. A covenant or a warranty of title may be so bound up with land that the assignee of the land will be able to sue the covenantor or warrantor.[1]
In another connection, the same learned authors observe:
The realm of mediæval law is rich with incorporeal things. Any permanent right which is of a transferable nature, at all events if it has what we may call a territorial ambit, is thought of as a thing that is very like a piece of land. Just because it is a thing it is transferable. This is no fiction invented by the speculative jurists. For the popular mind these things are things. The lawyer's business is not to make them things but to point out that they are incorporeal. The layman who wishes to convey the advowson of a church will say that he conveys the church; it is for Bracton to explain to him that what he means to transfer is not that structure of wood and stone which belongs to God and the saints, but a thing incorporeal, as incorporeal as his own soul or the anima mundi.[2]
A second reason for the tendency to confuse or blend non-legal and legal conceptions consists in the ambiguity and looseness of our legal terminology. The word "property" furnishes a striking example. Both with lawyers and with laymen this term has no definite or stable connotation. Sometimes it is employed to indicate the physical object to which various legal rights, privileges, etc., relate; then again—with far greater discrimination and accuracy—the word is used to denote the legal interest (or aggregate of legal relations) appertaining to such physical object. Frequently there is a rapid and fallacious shift from the one
