Ad Reinhardt in this cartoon was commenting on the non artist viewers arrogance asking 'what does this painting represent', as if painting is a window in which to view the world. Reinhardt was wryly illustrating that then in the 1940s, and today you don't have to ask that question. Abstraction or Non Objective art is of itself- self referential. The shock of the viewer in the second cell is the realisation that there is only the existential reading of anything in the temporal world.
