The Post-Impressionists rebelled against the Impressionists' naturalistic depiction of light and color. They continued using vivid colors and real-life subject matter, but emphasized geometric forms, distorted form for expressive effect, and used unnatural or arbitrary color. The movement was led by Paul Cézanne, Paul Gauguin, Vincent van Gogh, and Georges Seurat.
Clement Greenberg was probably the single most influential art critic in the twentieth century. he is best remembered for his promotion of the abstract expressionist movement and was among the first published critics to praise the work of painter Jackson Pollock who he championed as the greatest painter of his generation.
In 1877, after viewing Whistler's Nocturne in Black and Gold: The Falling Rocket in a contemporary art exhibition at the Grosvenor Galleries, John Ruskin wrote in the pages of Fors Clavigera, "I have seen, and heard, much of Cockney impudence before now; but never expected to hear a coxcomb ask two hundred guineas for flinging a pot of paint in the public's face." Whistler subsequently sued the great art critic for dismissing him as a fraud.
Van Gogh painted The Starry Night while undergoing treatment at the Saint-Paul-de-Mausole, a psychiatric hospital in Saint-Rémy-de-Provence in the south of France. Forbidden by the hosptial staff to paint his bedroom, he painted the view from his bedroom window no fewer than twenty-one times at different times of day and under various weather conditions, including sunrise, moonrise, sunshine-filled days, overcast days, windy days, and one day with rain. "Through the iron-barred window," he wrote to his brother in 1889, "I can see an enclosed square of wheat ... above which, in the morning, I watch the sun rise in all its glory."
In 2002, Chris Henshilwood discovered a piece of ochre decorated with a delicate geometric pattern in Blombos Cave on the southern Cape coast. He dated the piece conservatively at 77,000 years old; in fact, it could be as much as 100,000 years old.
Seeking to elevate popular culture to the level of fine art, Pop artists celebrated commonplace objects and people of everyday life. Even the labeling on the outside of a shipping box containing food items for retail has been used as subject matter in pop art, as demonstrated by Andy Warhol's Campbell's Tomato Juice Box.