The idea that physical disability is the result of extraordinary mental activity in childhood has, of course, been destroyed by numerous instances. There is the case of William James Sidis, for example, son of Dr. Boris Sidis, the well-known specialist in mental and nervous diseases. At the age of twelve, this boy delivered a lecture on the fourth dimension in Harvard University, where he is studying the highest branches of mathematics. He reads: Herodotus, Sophocles, Kuripides, Lucan, and other Greek writers, including Robinson Crusoe, and is well-versed in comparative philology and mythology. His extraordinary genius for knowledge has not in any way affected his health. He has a clear, ruddy complexion, is muscular and strong above other boys of like age, and is possessed of an extremely happy disposition and keen sense of humor.

Dr. Sidis believes that disease and nervousness are the result of worry, emotional excitement, and lack of interest, rather than study. He asserts that in his practice as a physician in nervous or mental diseases, he has never met a single case of nervous or mental trouble caused by too much thinking or overstudy. In his recent book on the training of children, Dr. Sidis says: "We do not take care to develop a love of knowledge in the early life of the child for fear of brain injury, and then when it is late to acquire the interest we force them to."  At tidy, and we carry them and feed them and stuff them like geese. What! You often get is fatty degeneration of the mental liver. 