In his text entitled “Modernist Painting”, Greenberg focuses on the development of painting between the 14th and 19th century and emphasizes on what distinguishes Modernist painting from previous forms of painting, particularly those of the Old Masters. Greenberg begins by relating Modernist art to Kantian philosophy claiming that, the same way Kant used reason in order to examine the limits of reason, Modernist art is when art became self critical because it uses the technique of art to draw attention to its status as art. Indeed, he explains how without this self-examination similar to that of Kant’s reflection on Philosophy, art would’ve been “assimilated to […] therapy” like religion, because it could’ve very simply valueless and reduced to simple entertainment. Pushing it further, he adds that “what had to be exhibited was not only that which was unique and irreducible in art in general”, but also the subject of painting specifically had to detach itself from other art forms and return to its own roots. Greenberg was then able to identify that what characterizes the uniqueness of each form of art is the nature of its medium: What he characterized as wholly unique to painting is the flatness of its two dimensional medium, and the purely optical rather than the tactile too. Indeed, he stresses on how Modernist painting separates three-dimensional illusion from its two-dimensional surface, reserving it for sculpture that is an art of three-dimensionality.
Therefore, unlike the Old Masters of paintings whose goal was to create depth of space and challenge the flatness of the medium, Modernist paintings focus on the nature of painting by reinforcing the medium’s purity and rejecting any “suggestion of a recognizable entity” that would subvert the two-dimensionality of the plane (This had started with the Impressionists). Greenberg continues by arguing that, although he claims “realist, naturalistic art had dissembled