On the psychology of microcephalics.

… Nature herself sometimes conducts experiments that help to shed light on many obscure areas of psychology. For example, we all know the great importance that observations of patients with a lesion of the insular, or central, lobe and contiguous parts of the frontal and temporal lobes have had in clarifying the act of human speech. Many properties of human memory have also become known to us from observations of patients. Finally, the universally acknowledged hypothesis that the activity of the mind depends on the activity of the brain is clearly demonstrated in psychiatric practice in cases in which mental life declines concomitantly with destruction of brain tissue. These things make mental anomalies scientifically interesting not only for the specialist but also for psychologists in general, and attentive study of the symptoms of mental disorders can unquestionably be of great benefit to professional psychologists even at the purely theoretical level. From this standpoint, people whose abnormal physic...