Factors of production
From Hobson's Choice
The factors of production are the main categories of economic inputs. Since Adam Smith, they have been listed as land, labor, capital, and entrepreneurship. In economics, the act of production consists of combining these products to produce commodities.
In the 19th century, the roles of capitalist and entrepreneur were effectively merged in economic analysis; in point of fact, however, the defining feature of modern economic organization is the separation of roles. Capital, as a factor, is institutionalized as finance capital; entrepreneurship is institutionalized as the firm. Additionally, during the same period land was subsumed as something entirely commoditized, like any other industrial input. It is assumed that capital-entrepreneurship can always buy land as needed.