Diseases must be very grave indeed before they become completely coextensive with their victims. That men are affected by their illnesses is obvious; but it is no less obvious that, except when they are almost in extremis, they are something more than the sum of their morbid symptoms. Dostoevsky was not merely personified epilepsy, Keats was other things besides a simple lump of pulmonary tuberculosis. Men make use of their illnesses at least as much as they are made use of by them.
– Aldous Huxley, “Meditations on El Greco,” Collected Essays (1958)