The Definition and Diagnosis of Mental Deficiency. Part II

Suspected deficiency of temperament, which provides by far the more perplexing problems, we may perhaps consider first. It is here that the psychographic scheme need's to be followed with great thoroughness and to be filled in with greatest detail. With these cases the question as to degree of deficiency resolves itself into two issues: how unstable is the patient, and what amount of instability is necessary to form a ground for his certification? If, with some authorities, we restrict mental defect to defect of intelligence alone, then it might seem that the criterion for temperamental or moral defect was given in the statutory clause relating to the moral imbecile. The instability, it may foe urged, is certifiable as deficiency when it is so extreme as to issue in incorrigible vice or crime. But, unfortunately for this interpretation, \icious and criminal propensities, however violent and refractory they may be, form, according to the statute, no ground for certification, unless coupled with signs of early and permanent defect. Hence, if mental defect implies inadequacy of intelligence alone, the diagnosis after all will turn upon the question. is the patient s intellectual inadequacy sufficientlv profound to be characterised as deficiency* If, however, as I have urged, the term mental defect be extended to cover deficiencies of temperament, as well as of intelligence, then temperamental instability is not to be identified merely with moral imbecility : it falls also under the definition of feeblemindedness. To be certifiable, such instability need not of necessity include vicious or criminal behaviour. It need only be so pronounced