We have noted that it is very difficult to understand what the neural bases for such special abilities as Galton speaks of could be; that they are social, not neural or psychological units. A view of a large number of inherited elements all of which contribute to what we call general intelligence and each of which is slightly more necessary to some vocation than others, would account for all the observed facts, is neurally imaginable, and does not need to view ability to be a “judge” or “artistic talents” as biological entities. It further explains the differences in their limited abilities of mentally deficient children. Burt says in this connection: “Among children of special (M.D.) schools, the evidence for a general factor underlying educational abilities and disabilities of every kind is not so clear. In administrative practice, ‘mental deficiency’ implies among different children deficiencies in very different capacities, both general and specific.” (Cyril Burt: _The Distribution and Relation of Educational Abilities_, p. 83.) For these reasons it is justifiable to attempt to present evidence of the inheritance of school abilities with a view to showing that school abilities are not dependent upon special inherited aptitudes, as teachers so often assume, but that general intelligence is the only inherited cause of disparity in product. Investigations where the correlation between educational product and intelligence, irrespective of chronological age, was less than around .75, used data where many removable causes were not removed, and consequently measured results of the environment as well as heredity. A case such as this follows: “The influence of inheritance upon a _very specific_ mental quality, namely, spelling ability, has been tested experimentally, although here there is some difficulty in separating the influence of heredity from that of environment. Earle studied the spelling ability of 180 pairs of brothers and sisters who had uniform school training and found a correlation of .50. This means that if one child deviated by a certain amount from the average child in spelling ability, his brother or sister would deviate from the average child just half as much; that is, he would resemble his brother or sister to that extent.” (Hollingworth and Poffenberger: _Applied Psychology_, p. 44.)