(_d_) In the case of children we may assume, and in the more backward races of men we may suspect, that the comparison of judgments is difficult, or sometimes even impossible, because of the imperfect development of the cerebral cortex. There must be some structural conditions of the free flow of energy through all organs of the brain, corresponding with the associability and comparability of all ideas. We may doubt if these conditions are complete even in good cultivated minds; since everybody finds one or another study or art especially difficult for him, or the freeing of himself from this or that sort of prejudice especially repugnant. And it is not only deliberate comparison that is hindered in the immaturity of the brain, but also that automatic process (more or less unconscious) of assimilation and discrimination to which (I think) we owe most of the results of abstraction and generalisation that may seem to have required purposive comparison. Such imperfections of structure, greatest at the lowest levels of organisation, and gradually decreasing as ideal rationality is approached, we may call “incoördination”; and, so far as it obtains, the results must be somewhat similar to the discoördination, the breaking down or interruption of organic efficiency, that occurs in hysteria, hypnosis and some forms of insanity. One of the results probably is suggestibility—the tendency to accept what is told, or insinuated, without examination; for freedom from this common liability depends (apart from the contra-suggestible disposition) upon the rapidity and definiteness with which one can compare that which is suggested with present fact or with one’s knowledge and former experience; and this is hindered by incoördination.
Effective incoördination may, however, be merely functional for want of practice in thinking; and it exists often enough in civilised people, because they have not even the desire to be consistent. In either case, whether from defective structure or from the dull inertia of disuse, there will be failure of comparison and, therefore, of criticism, and also (we may suppose) a greater intensity of imagination and of dreaming and a liability to hallucination, such as is said to be frequently the case with immature minds.