They thought him reasonable and praised his common sense; but he knew that his placid expression was no more than a mask, assumed unconsciously, which acted like the protective colouring of butterflies; and himself was astonished at the weakness of his will. It seemed to him that he was swayed by every light emotion, as though he were a leaf in the wind, and when passion seized him he was powerless. He had no self-control. He merely seemed to possess it because he was indifferent to many of the things which moved other people.