Knowledge of amnesia is dependent upon the subject's statement. He can tell us what he will. If he has studied the subject well, he can mislead us. He may have motives for fabricating. He may benefit, he thinks, financially, socially or in other material ways, by inventing an amnesia. A history of grave injury may produce avoidance of danger or of unpleasant work. A medical history, which the patient may think unusual, may give him prestige or sympathy. Finally, he may invent an amnesia to give the doctor a good story or to “pull his leg.”