THE AMERICAN
Journal of Psychology
Vol. III JANUARY, 1890 No. 1
THE INSANITY OF DOUBT.
Philip Coombs Knapp, A. M., M. D.
Insanity of doubt is a form of mental disturbance which is brought about by certain disturbances of the psychical pro- cesses, to which the various names of insistent or fixed ideas or imperative conceptions have been given. The imperative conception or representation (Zwangsvorstellung) plays as important a part in the genesis of the insanity of doubt as the delusion does in the genesis of paranoia. Therefore this form of mental disturbance has often been termed the "malady of fixed ideas," and before studying it, these fixed ideas or imperative representations must be considered.
Westphal defines them as "those representations which enter into the foreground of consciousness without and even against the volition of the individual affected, who, in other respects, is still possessed of an intact intelligence. They are not brought about by any affective or emotional condi- tion. They cannot be dispelled. They prevent the normal current of ideas. The patient recognizes them as abnormal and foreign, and opposes them with his entire consciousness." Although this definition serves in many cases, it excludes too much. The mental obsession by some overpowering emotion cannot, of course, be classed in the same category as the
