The economic theory of money is generally expressed in a terminology that is not economic but juristic. This terminology has been built up by writers, statesmen, merchants, judges, and others whose chief interests have been in the legal characteristics of the different kinds of money and their substitutes. It is useful for dealing with those aspects of the monetary system that are of importance from the legal point of view; but for purposes of economic investigation it is practically valueless

Source: mises.org