The Story of Art, E.H. Gombrich, page 564, Zettel 160

What upset the public about Expressionist art was, perhaps, not so much the fact that nature had been distorted as that the result led away from beauty…But the men who claimed to be serious artists should forget that if they must change the appearance of things they should idealize them rather than make them ugly was strongly resented. But (Edvard) Munch might have retorted that a shout of anguish is not beautiful, and that it would be insincere to look only at the pleasing side of life. For the Expressionists felt so strongly about human suffering, poverty, violence and passion, that they were inclined to think that the insistence on harmony and beauty in art was only born out of a refusal to be honest. The art of the classical masters, of a Raphael or Correggio, seemed to them insincere and hypocritical. They wanted to face the stark facts of our existence and to express their compassion for the disinherited and the ugly. It became almost a point of honour with them to avoid anything which smelt of prettiness and polish, and to shock the ‘bougeois‘ out of his real or imagined complacency. -