THE PATHOGENESIS OF HALLUCINATIONS AND DELUSIONS

The distinction between pathogenesis and etiology deserves more attention than it usually receives and is almost completely ignored in discussions of the causes of symptoms of mental disease.

Abstract

The distinction between pathogenesis and etiology deserves more attention than it usually receives. Though its value in neurology has been recognized, it is almost completely ignored in discussions of the causes of symptoms of mental disease. The distinction may be illustrated by an example, hemiplegia. In explaining the occurrence of hemiplegia one may say two things: (1) The pyramidal tract has been interrupted, and (2) there is (I shall suppose) a large cerebral hemorrhage. The first statement refers to the structures which must be damaged before there can be hemiplegia; it is a statement of pathogenesis. The second refers to the agent which has produced this damage; it is a statement of etiology. No neurologist in explaining a case of motor loss would be satisfied with a statement concerned exclusively with etiology; he would regard it as one sided. But this one-sidedness is found in most discussions of the causes