(A) The "good humor" hypothesis of health, which suggested that health is a state of body and mind where there is a balance of certain humors, was disapproved by William Harvey.
$1$. William Harvey, an English physician, discovered blood circulation using experimental methods.
$2$. He demonstrated that people with "black bile" (associated with hot personality in the hypothesis) did not necessarily have a higher body temperature, which he proved using a thermometer.
These findings showed that health is not merely a balance of humors, but is influenced by the neural and endocrine systems, which in turn regulate our immune system.