This symptom is frequently found in connection with depersonalization. It is due to the repression of an identification, and a special heterosexual type of erotized thinking. It is chiefly a defense against sexual curiosity which may at the same time unconsciously give opportunity to satisfy this curiosity.

When a feeling of stupidity is the leading symptom, Oberndorf believes a certain cleverness or stupidity has been perceived as a sex quality of one parent and '… feelings of stupidity are most apt to develop when identification is with the dull parent of the same sex'. This is by no means invariable, and examples of exception are given.