The most significant consideration with regard to paranoia is the fact that it is practically always hereditary. Krafft-Ebing said that he never saw a case of true and reasonably well developed paranoia without hereditary taint. This does not imply, of course, that the same symptom of delusions exists in several generations, but some serious mental peculiarity is always found to exist in the preceding generation. Other authorities are not quite so sweeping in their assertion of heredity for these cases, though practically all are agreed that in over 80 per centum of the cases, some hereditary element can be traced without overstretching the details of family history that are given. Paranoia occurs a little more commonly in females than in males. As it is of hereditary origin, it is not surprising to find that the peculiarities are noticed very early in life, though they may not be sufficiently emphasised to attract the attention of any but acute observers, who are brought closely in contact with the patients. Even in childhood, patients who subsequently develop serious forms of paranoia, usually have been shy, backward, inclined not to play readily, irritable, peculiar, precocious, prone to spend much time in study at an age when they ought to be interested mainly in sports, and they are generally old beyond their years. A typical example of this was Friederich Nietzsche, the German philosopher, who died a few years ago in an insane asylum. Olla Hanssen, Nietzsche's biographer, who carefully collected the family accounts of the philosopher's childhood, said that he did not talk until much later in childhood than is usual. "As a boy he was retiring and solitary in his habits. During his school days he was always interested in books not in sports, in lonely walks not in young companions." A history of this kind will be found in the early career of many queer folk. Very often these old-fashioned traits are a source of pleasure to parents and sometimes even to teachers. During childhood, however, the sports of childhood should satisfy the child, and abnormalities of interest in things outside of childhood's sphere are always suspicious. The growing {286} organism needs, first of all, muscular exercise, and after that the freedom of mind that comes with spontaneous play. It may be said, in passing, that the walk of a city child with its maid, when even the child's choice in the matter of where it shall walk is not consulted and the maid's will is constantly imposed, is the worst possible training for spontaneous action or volition in later life.