The Victorian period witnessed a new interest in understanding human psychology, the mind, and cases of insanity or madness. For a long time, madness had been conceived of in either supernatural terms, or sometimes as a kind of divine punishment. In the Victorian period, a more scientific approach to madness began to emerge. It started to be perceived as a disease, which could be studied, diagnosed, and treated. At the same time, however, there began to be more doubts about how certain one could be of someone's status as sane or insane. As populations congregated more and more in larger urban centers and there was greater mobility from place to place, it was often not possible to know someone's history or origins. This made it more plausible that someone could simply be masking his or her true self. This anxiety cut both ways, igniting fears both that someone could seem sane and actually be hiding madness, or that a sane person could be wrongfully accused of madness and wind up imprisoned in an asylum as a result.
One particular form of insanity that was widely discussed in the Victorian period was called "monomania." As Athena Vrettos explains, monomania "denoted a condition in which a break in the psyche—a separation of the faculties of emotion, reason, and will-produced a singular fixation, or aberration, within a mind that was otherwise rational. Monomania posited a form of partial insanity in which the afflicted subject could appear to be entirely normal and sane in all areas of behavior except one" (79). This condition was particularly dangerous because it suggested that madness could coexist alongside generally rational behavior.
Madness, whether it was monomania or another variety, was strongly associated with heredity. If someone had family members, especially immediate family members, who had suffered from mental illness, the expectation that he or she would also display traits of madness was very strong. In a kind of paradox, the paranoia about eventually going mad could itself trigger a kind of obsession or madness. The idea of heredity emphasized a concept of self-development that favored nature over nurture: while external influences were considered important, someone's natural predispositions were rooted in his or her racial, class and family background and were almost impossible to overcome.
During this time period, a particular connection was established between women and madness. While men were also understood as able to suffer from insanity, a higher number of inmates in asylums were female. Because the expectations around proper female behavior were so strict, any kind of departure from that behavior, such as being outspoken, aggressive, disinterested in nurturing children, or sexually promiscuous could be perceived as signs of insanity. Because women had fewer legal rights, it was also fairly easy for them to be institutionalized by their husbands or fathers. Other nineteenth-century literary texts that explore the connection between women and madness include Charlotte Bronte's novel Jane Eyre and Charlotte Perkins Gilman's short story The Yellow Wallpaper.