The quandaries of business valuation have marked the pedagogy of business administration since early attempts at institutionalizing the managerial discipline. It is however now commonly admitted, at least in legitimate financial and entrepreneurial circles, that the value of a business (that is, the monetary assessment of a functioning enterprise established in a competitive environment) resides primarily in its earning power or, in other words, that what a business is worth equals its capacity to generate a stream of revenues for the investor or investors that provide it with funding. How did this idea take shape and how did it permeate the business mind? An examination of early pedagogical materials at the Harvard Business School (an influential reference for the socialization of the businessperson) and, in particular, of the vagaries of the idea of capitalization and its exercising in the classroom provides a fine occasion to advance understanding of the meaning of such ideals of business and business value, and of their institutionalization. This empirical study can, in turn, be employed in order to discuss and refine critically our interpretation of what a convention of economic valuation is and how it operates.