'we are told [by Marshall] that [wealth] consists of two classes of goods, which together constitute "economic goods." If we ask what quote economic goods" far, we are informed that quote economic goods" include quote those goods, and only those, which come clearly within the scope of economic science, as defined in Book I." (p. 127). But as "economic science" is there defined as "the study of Wealth," we are clearly being led by the nose in a circle. Wealth is defined as consisting of all those goods, and those only, which come clearly within the scope of the Science of Wealth.' -- J.A. Smith, “On Some Fundamental Notions of Economics,” Economic Review, 1913.