Wherever the moon and stars are aligned with a certain astrological sign, they correlated with a body part, bodily system, or the four humors. The four humors separate the body into four parts just as there are four elements. The four humors of the human body are yellow bile, black bile, phlegm, and blood; it was believed that these all needed to be in balance in order to keep up with your health. These humors were used directly to treat illness alongside Zodiac Man and were also used to explain and simplify concepts to patients. Europe was, at the time, required by law to calculate the moon’s positioning before taking action on a patient or any kind of medical procedure. If the moon was not in its correct positioning, nothing was able to be performed because it was deemed unsafe. They used a volvelle, a rotating calendar, to calculate the moon’s position as well as multiple almanacs which described different phases of the moon.