The Development of Intelligence in Children

ority. It remains to complete the preliminary work, to standardize it, to show how far these methods work out when applied to real facts. After the theory must come the proof. It will not be a question here of anything but the psychological method. It is the only one which is ripe for complete practical purposes. Other methods can only give accessory indications; but these already permit determinations of intellectual inferiority. This is our conviction; we are now going to give the palpable demonstration. The psychological examination of a subject lasts on an average 40 minutes. We made in the beginning many useless tests with each child, because we were doing a work of investigation; we were groping; now that one knows what to look for, one can proceed more rapidly, and we believe that a half-hour will suffice to fix the state of the intellectual development of each child. We shall study successively with our measuring scale of intelligence: 1. Normals. 2. Subnormals in institutions. 3. Subnormals in primary schools. I. Normal Development Of The Intelligence With Children From Three To Twelve Years Old Normals figure here as terms of comparison. We have been obliged to make these lengthy studies, because, up to the present, nothing of the kind existed. So far as we know, there is no work that contains the precise and detailed history of the development of the intelligence of a child. The most complete monographslike those of Allen Gilbert1 p...