The “scientific” thought of a chIna warlord & intellectual Cao Zhi whose clan brought an end to the Later Han during a past epidemic that ripped through the late Han world. An e.g., of rationalism the recurs through diverse cultures in a rather similar form.
In the twenty-second year of Jian-an (217 C.E.), the infectious disease roamed about, every family experienced the pain of death, and every household was mourning with sad outcry. Some families died out com- pletely, other clans perished altogether. People thought that the disease was caused by ghosts and spirits…. This is because yin and yang are dis- located and hot and cold weathers missed their proper time. This is why disease comes about. And yet foolish people hang talismans to exorcise it, which is quite laughable.12
In contrast, one of the most important rites performed by the Han court, the Nuo, was to ward off ghosts believed to cause plagues during the midwinter La festival. It was officiated by a shaman fangxiang wearing a bear- mask with four golden eyes & skin-drape.