Once I happened to go to the asylum for the insane in New York, and the physicians very kindly laid before me a number of skulls showing the different cavities in the brain and the spots of decay which had caused insanity in the life of the patients. There is always a sign of it in the physical body. It may be apparent suffering or it may be some decay at the back of it, yet it is not known. I asked them, "I would like to know whether the cavity brought about the insanity or the insanity brought about the cavity?" Their argument was that the cavity brought about the insanity. But it is not always so, the mental disorder is not always caused by a cavity in the brain; for the inner being has a greater influence on the physical being than the physical body has on the mental existence.