O'Gorman presents the thesis that many cases diagnosed as mental deficiency may actually be cases of deteriorated schizophrenia that began very early in life. He suggests that the very earliest and perhaps most severe schizophrenic processes produce a clinical picture of idiocy or imbecility, whereas less severe psychotic states beginning at a somewhat later period may result in milder forms of feeblemindedness. In testing this hypothesis, the author re-evaluated a group of diagnosed mental defectives and found that twenty-nine per cent of the patients were psychotic; their symptoms were indistinguishable from deteriorated schizophrenia.