A Brief History of Money and Religion
Parallel to paper currency as money, Duchamp's work represents the "dematerialization" of art, in which the artist's hand is no longer required for something to be considered art.
Work of this nature begins to call into question the opposition between art and non-art. Clement Greenberg defined the infiltraton of industrialization into art as the debasement of art by "low art." Walter Benjamin argued that when "high" art becomes "low," the "aura of art" disappears, although he also saw liberating possibilities for art in the age of mechanical reproduction. Taylor argues that high and low have a parasitic relationship, which is not necessarily negative or deadly, but rather, vital: the two feed off each other.  In any case, Duchamp's Fountain marks the beginning of art affected by industrialization and therefore by the economic sphere in an unprecedented way.
Kurt Schwitters, 1919, Rossfeld Merzbild. Schwitters uses the detritus of commerce to make collages as art. "Merz" comes from kommerz, the German word for commerce. Taylor quotes Rosenberg on collage: "... it brings to an end the age old separation between the realm of art and the realm of things. With collage, art no longer copies nature or seeks equivalence to it; an expression of the advanced industrial age, it appropriates the external world on the basis that it is already partly changed into art."  Schwitters himself said, "My ultimate aspiration is the union of art and non-art in the Merz total world view." 
This example of 1930s domestic architecture illustrates the past and future working out their differences. The allusion to the classical temple is seen in the pediment and columns, while the influence of mass production is evident in the model number for the house.
By the 1950s, the industrial economy is entering the Electronic Age.