In the early literature of mental defect there are allusions to behaviour, shown by defective children, which would now tend to be regarded as psychotic. This is probably one factor which has led psychiatrists into thinking of psychosis in childhood as an exceedingly rare occurrence. It now seems at least possible, if not probable, that many cases of early psychosis have been missed because the end-result has been equated with mental defect. In a sense it could be so classed since psychotic children are very often rendered ineducable by reason of their disorder, which sometimes seems to date “from birth” (Kanner, 1943), and in others certainly arises at an early age. However, the term “arrested development of mind” is less applicable, since the mind of the psychotic child appears to develop in a distorted and unbalanced way, showing some faculties to be absent and others apparently developed in a precocious manner (Bender, 1947).