Lunatic: the story of a word between Gospel, medicine and law
From the Greek seleniazesthai to the lunaticus of the Vulgate, from Blackstone to the Lunacy Act of 1845: how the Moon gave its name to madness and moodiness.
The word «lunatic» in Italian today describes a person of unstable mood, who changes frame of mind quickly. Originally, however, it had a far more precise and serious meaning: it designated those struck by illnesses of the mind or by sudden fits believed to be caused by the Moon. Its history runs through ancient medicine, sacred texts, English law and everyday speech, and shows how deeply rooted was the idea of a lunar influence on the mind.
From Greek to Latin
In the Gospel of Matthew, in the seventeenth chapter, a father approaches Jesus asking mercy for his son, who suffers violent fits and often falls into the fire and into the water. The Greek text uses the verb seleniazesthai, «to be moonstruck»; Jerome's Latin Vulgate renders it as «lunaticus est». From there the term passed into the European languages, and for centuries it was also used to denote epilepsy, whose seizures were believed to be linked to the phases of the Moon.
The idea of a relationship between the Moon and the mind was not only a popular one. Various ancient and medieval physicians and naturalists held that the Moon, mistress of moisture, acted upon the brain, considered a cold and moist organ, just as she acted upon the tides. This explanation, consistent with the physics of the time, survived into the modern age and helped give the word credibility in medical and legal texts as well.
The lunatic in law
In English law the term «lunatic» had technical force for centuries. William Blackstone, in the Commentaries on the Laws of England published between 1765 and 1769, distinguished the idiot, lacking reason from birth, from the lunatic, who had lost the use of reason and might enjoy lucid intervals, once thought to be related to the phases of the Moon. The distinction had precise consequences for the capacity to manage property and to enter into contracts.
In 1845 the British Parliament passed the Lunacy Act, which set up a permanent commission to oversee asylums, together with a law requiring the counties to provide public institutions. The term survived in British legislation into the twentieth century, when it was replaced by more precise medical expressions. The English word lunacy, madness, still preserves this celestial origin today.
Legends, statistics and language
In popular culture the idea that the full moon makes people more agitated survived for a long time. It was said that on nights of the full moon quarrels, crimes and emergency admissions increased. Numerous statistical studies carried out in the twentieth century in hospitals, emergency departments and police stations found no reliable correlation between lunar phases and these phenomena, but the belief remains widespread even among those who work in such settings.
The Italian language has kept above all the softened meaning of the term. A lunatico is someone whose mood changes as the Moon changes her appearance, a comparison also found in expressions such as «having a crooked moon». In literature the figure of the lunatic often has a melancholy or comic tone, halfway between the dreamer and the eccentric, now far removed from the harshness of the old diagnoses.
The history of the word «lunatic» is an example of how a belief about the sky can shape for centuries the language of religion, medicine and law. Today we know that the Moon does not govern the human mind, but the term continues to recall the ancient conviction that the rhythms of the cosmos and those of the soul were closely intertwined.