The conceptions of the causes of epilepsy are many and confusing. Any discovery which reveals the causes underlying the convulsive manifestations will tend to clarify the situation. I have little sympathy with the view so often expressed of late that the mental (dementia), and even the paralytic and other somatic disorders of epilepsy, are secondary to the psychogenically determined convulsive attacks. The more I study the experimental work and the anatomic, biochemical and pathologic data bearing on the question, the more tenaciously do I hold to the belief that if the convulsions in epilepsy are once satisfactorily explained, the whole problem will be placed on a sound basis. While it is not possible to synthesize all theories of the causation of epilepsy, the psychogenic factor may be readily assimilated in our discussion. The staunchest upholder of the psychanalytic conception is Dr. L. Pierce Clark.1He believes that epilepsy is