I. PSYCHOPATHIC CONDITIONS IN THE INTELLECTUAL LIFE—1. CONDITIONS OF DEFICIENCY.—The intellect of a group, like that of the individual, has its limits, beyond which it is not possible to educate it. This is conspicuously seen in intellects below the normal, such as in feeble-minded persons. No amount of training can cure their radical defects and make them the equals of their average associates. These are instances of intellectual deficiency. It may express itself either in some degree of imbecility or in the active form of criminal habits. Another class do not seem below the average in general powers, may, perhaps, appear in various directions above it; but they have some twist or obliquity in their mental make-up which separates them from their fellows, usually to their detriment. In common life such persons are known as “cranks” or “eccentrics,” men of one idea and paranoiacs. They are examples of intellectual perversion. Ethnic psychology can also supply abundant instances of this character. _(a) Imbecility._—To say that there are tribes or whole peoples actually imbecile would perhaps be going too far. Yet this has been asserted of some by competent observers. Mr. Horatio Hale, who was among the native blacks of Australia, related that the impression they produced on his mind was one of “great natural obtuseness, downright childishness, and imbecility.” The only arguments which availed with them were “such as we should use towards a child or a partial idiot.” Mr. Hale attributed this to generations of semi-starvation and malnutrition, and was so convinced of this that he believed the most favoured race would, by similar conditions, be reduced to the same low intellectual stage. A prevailing inability to judge of evidence is common among many peoples and classes, and this is a marked sign of mental deficiency. They mistake associations of time and place for relations of cause and effect, and their reasoning is vitiated in consequence. Superstition is fostered by this mental obliquity. The casual objective relation is mistakenly assumed as the subjective necessity. This is especially common among savages, and the illiterate classes of higher culture. It is a mark of mental inferiority tending to irrational action and confusion of thought. In civilised communities those of the population who are thus constituted form the “dependent” class, incapable of making their own living, and supported either by their families or the state. They may thus survive and reproduce their kind, but ethnic groups afflicted with such intellectual retardation either perish or become subject to those with higher gifts.