phlegm theory
Most Popular Theories of Consciousness Are Worse Than Wrong
According to medieval medicine, laziness is caused by a build-up of phlegm in the body. Phlegm is a viscous substance. Its oozing motion is analogous to a sluggish disposition. The phlegm theory has more problems than just a few factual errors. After all, suppose you had a beaker of phlegm and injected it into a person.