Insanity is a anachronistic term for a spectrum of behaviors characterized by certain abnormal behavioral patterns. Insanity may manifest as violations of any number of potential societal norms and mores. In the psychiatric community it no longer has a clinical use, and has been defunct as a diagnosis since the late 19th century. In modern usage insanity is most commonly encountered as an informal unscientific term denoting mental instability, or a vernacular term connotating a psychotic disorder. DSM categories will use the term psycho-pathology in place of the archaic notion of insanity. It does currently maintain a narrow legal usage, in the context of the insanity defense. However, in the 20th century the insanity defense is rarely employed, and even more rarely accepted by local and state courts.
In English, the word "sane" derives from the Latin adjective "sanus", meaning "healthy". The line from Juvenal, "mens sana in corpore sano" (Saturae, Book IV, X, line 356) is often translated to mean a "healthy mind in a healthy body". From this perspective, insanity was considered as poor health of the mind, not necessarily of the brain as an organ (This view would not become commonplace until the beginning of the 17th century). Much of the course of western medicine was dictated by the Roman physician, Galen, who dictated that pathological symptoms were the result or an inbalance in the body's humors. Therefore, it followed amongst early physicians that the cure of insanity, as a disease, as a restoration of mental faculties through attaining homeostasis.
Another Latin phrase related to our current concept of sanity, or insanity, is "compos mentis", or "of a composed mind", and the euphemistic term for insanity is "non compos mentis". As maxims of law, "mens rea" means having had criminal intent, when the act "actus reus" was committed.
Through the centuries, and among different cultures, there have been various theories regarding the origin and treatment of insanity. Many of which have been dismissed as pre-scientific, or misguided theories. However, the current understanding and etiology of the theory of the Schizophrenic mind is still currently unknown by modern medicine.
History of the Perception of Insanity
Mental Illness as 'Woodness'
The term Woodness was originally applied in Anglo-Saxon circles as a condition where the intelligible mind is separated from the vegetative soul. Woodness appears to mean that an individial is literally out of thier mind; or rather, that the rational mind is in a disconnected relationship with itself. Traits attributed to 'Woodness' might be related to the modern notion of Schizophrenia, or split-mindness. This mental condition is reflected in populat English literature as late as Geoffrey Chaucer's work 'Canterbury Tales', in the 14th century. Lines alluding to mental illness include, "What sholde he studie and make hymselven wood", "armed, and looked grym as he were wood", and "the hunted is, for her hunger wood".