Remember that a lot of what we're used to was new at the time of the Expressionists. When you look at Matisse's Girl with Green Eyes painting, for example, it's hard to believe his contemporaries were outraged by it and regarded it as grotesque. Matisse biographer Hilary Spurling says: "The confident gaze and frank body language of these young women, painted almost a century ago, speak directly to us today, although contemporaries could see little in these portraits but meaningless jumbles of color outlined in ugly black brushstrokes."3
In his book Bright Earth: The Invention of Color, Philip Ball writes: "If Henri Matisse made colour the substance of pleasure and well-being, and Gauguin revealed it as a mysterious, metaphysical medium, van Gogh showed color as terror and despair. Munch's remark apropos of The Scream (1893) that 'I ... painted the clouds like real blood. The colours were screaming' echoes van Gogh's sanguine comment on The Night Cafe -- 'a place where one can ruin one's self, go mad, or commit a crime'."4