He was excellently qualified for the task he undertook. He had a well-trained scientific mind, and a large experience of city life. He was an independent thinker, and perfectly free in his criticisms; but he reverenced the great men who had gone before him, and knew nothing of the temptation to try to raise himself by disparaging them. Though he has shown more clearly than perhaps anyone else the danger of a careless application of theory, he saw with great distinctness the need of its aid in dealing with complex economic problems. 'If you attempt to solve such problems,' he says, 'without some apparatus of method, you are as sure to fail as if you try to take a modern military fortress—a Metz or a Belfort—by common assault.'