"Colour was for Klee the 'imponderable' and thus individual element in the picture. ..... As Klee once commented: 'Colour has always had something secretive about it that is difficult to grasp. This mysterious quality penetrates the mind. The colours are the most irrational elements in painting. They possess something suggestive, a suggestive power."
Paul Klee, 'Fire in the Evening", l929, oil on cardboard.
