Cheyne did not, however, see weak nerves as entirely unhealthy. The thinner and more fragile the nerve, the more quickly it could transmit a quality called “sense.” “Sensibility” conveyed aesthetic, intellectual, and social refinement, made one a “quick Thinker,” and provided the “most lively imagination.” Talented people were born with “organs finer, quicker, more agile, and sensible, and perhaps more numerous than others.” In contrast, “brute Animals have few or none, at least none that belong to Reflection; Vegetables certainly none at all.” Sensibility could be cultivated, but was also seen to be biologically rooted and inborn, determined directly by the exquisiteness and delicacy of one’s nerves. It was simply an unfortunate irony that refinement of nerves coupled so tightly with susceptibility to illness. People of good breeding, high sensibility, and excellent moral character were expected to come down with nervous disorders, like hysteria, hypochondria, or the “Vapours.”
Cheyne’s description of the nervous system and its disorders mirrored the clearly demarcated race and class boundaries of the time: the upper class with their weak nerves and sharp senses were biologically built for sedentary and intellectual professions, whereas the working class’s (and African’s) robust nerves and dull senses had the perfect build and aptitude for physical labor. But this logic presented a puzzle when it came to women, as they suffered from hysteria and other nervous disorders with greater frequency than men, but were not considered intellectually superior beings.