Simon's face stays fairly neutral while Enjolras is talking. None of this is precisely new to him; it's still appalling, of course, but not shocking.

"Some of those are closer to the truth than others, of course," he says. "The components of the body are considerably more complicated than the old idea of humors, but it is true that an imbalance of body chemistry can cause illness. And physical contact definitely does spread some diseases, though not all ... I can tell you that bleeding as a treatment for illness has been completely discredited."