decisive features that distinguish one cultural era from another. In all phases of material civilisation these preferential advantages are sought and valued. Classes or groups which are in a position to make good a claim to such differential advantages commonly come, in due course, to put forward such claims; as, _e.g._, the priesthood, the princely and ruling class, the men as contrasted with the women, the adults as against minors, the able-bodied as against the infirm. Principles (habits of thought) countenancing some form of class or personal preference in the distribution of income are to be found incorporated in the moral code of all known civilisations and embodied in some form of institution. Such items of immaterial wealth are of a differential character, in that the advantage of those who secure the preference is the disadvantage of those who do not; and it may be mentioned in passing, that such a differential advantage inuring to any one class or person commonly carries a more than equal disadvantage to some other class or person or to the community at large.[6] When property rights fall into definite shape and the price system comes in, and more particularly when the practice of investment arises and business enterprise comes into vogue, such differential advantages take on something of the character of intangible assets. They come to have a pecuniary value and rating, whether they are transferable or not; and if they are transferable, if they can be sold and delivered, they become assets in a fairly clear and full sense of that term. Such immaterial wealth, preferential benefits of the nature of intangible assets, may be a matter of usage simply, as the vogue of a given public house, or of a given tradesman, or of a given brand of consumable goods; or may be a matter of arrogation, as the King's Customs in early times, or the once notorious Sound Dues, or the closing of public highways by large land-owners; or of contractual concession, as the freedom of a city or a guild, or a franchise in the Hanseatic League or in the Associated Press; or of government concession, whether on the basis of a bargain or otherwise, as the many trade monopolies of early modern times, or a corporation charter, or a railway franchise, or letters of marque, or letters patent; or of statutory creation, as trade protection by import, export, or excise duties or navigation laws; or of conventionalised superstitious punctilio, as the creation of a demand for wax by the devoutly obligatory consumption of consecrated tapers, or the similar devout consumption of and demand for fish during Lent.