Ecology is the touchstone of Hundertwasser's sensitivity, the sensitive cytoplasm of his fifth skin. Hundertwasser is naturally "green", just as he is naturally a painter, Austrian, cosmopolitan or pacifist. Since his earliest childhood he had displayed a hypersensitivity to his surroundings. Nature is the supreme reality, the source of universal harmony; his immense respect for nature very soon aroused in him the desire to protect it against the attacks made on it by man and industry.