This precocity is morbid and atavistic; it may be observed among all savages. The proverb, “A man who has genius at five is mad at fifteen” is often verified in asylums.[42] The children of the insane are often precocious. Savage knew an insane woman whose children could play classical music before the age of six, and other children who at a tender age displayed the passions of grown men. Among the children of the insane are often revealed aptitudes and tastes--chiefly for music, the arts, and mathematics--which are not usually found in other children. _Delayed Development._--Delay in the development of genius may be explained, as Beard remarks, by the absence of circumstances favourable to its blossoming, and by the ignorance of teachers and parents who see mental obtusity, or even idiocy, where there is only the distraction or amnesia of genius. Many children who become great men have been regarded at school as bad, wild, or silly; but their intelligence appeared as soon as the occasion offered, or when they found the true path of their genius. It was thus with Thiers, Pestalozzi, Wellington, Du Guesclin, Goldsmith, Burns, Balzac, Fresnel, Dumas _père_, Humboldt, Sheridan, Boccaccio, Pierre Thomas, Linnæus, Volta, Alfieri. Thus Newton, meditating on the problems of Kepler, often forgot the orders and commissions given him by his mother; and while he was the last in his class he was very clever in making mechanical playthings. Walter Scott, who also showed badly at school, was a wonderful story-teller. Klaproth, the celebrated Orientalist, when following the courses at Berlin University, was considered a backward student. In examination once a professor said to him: “But you know nothing, sir!” “Excuse me,” he replied, “I know Chinese.” It was found that he had learnt this difficult language alone, almost in secret. Gustave Flaubert “was the very opposite of a phenomenal child. It was only with extreme difficulty that he succeeded in learning to read. His mind, however, was already working, for he composed little plays which he could not write, but which he represented alone, playing the different personages, and improvising long dialogues.”[43] Domenichino, whom his comrades called the great bullock, when accused of being slow and not learning so fast as the other pupils, replied: “It is because I work in myself.” Sometimes children have only made progress when abandoned to their own impulses. Thus Cabanis, although intelligent, was regarded at school as obstinate and idle, and was sent home. His father then decided to risk an experiment. He allowed his son, at fourteen years of age, to study according to his own taste. The experiment succeeded completely.