MORAL INSANITY, med. jur. A term used by medical men, which has not yet acquired much reputation in the courts. Moral insanity is said to consist in a morbid perversion of the moral feelings, affections, inclinations, temper, habits, and moral dispositions, without any notable lesion of the intellect, or knowing and reasoning faculties, and particularly without any maniacal hallucination. Prichard, art. Insanity, in Cyclopaedia of Practical Medicine
2. It is contended that some human beings exist, who, in consequence of a deficiency in the moral organs, are as blind to the dictates of justice, as others are deaf to melody. Combe, Moral Philosophy, Lect. 12.
3. In some, this species of malady is said to display itself in an irresistible propensity to commit murder; in others, to commit theft, or arson. Though most persons afflicted with this malady commit such crimes, there are others whose disease is manifest in nothing but irascibility. Annals D'Hygiene tom. i. p. 284. Many are subjected to melancholy, and dejection, without any delusion or illusion. This, perhaps without full consideration, has been judicially declared to be a "groundless theory." The courts, and law writers, have not given it their full assent. 1 Chit. Med. Jur. 352; 1 Beck, Med. Jur. 553 Ray, Med. Jur. Prel. Views, Sec. 23, p. 49.