Beth Cavener Stichter was intrigued by the notion which is the basis of Hippocratic medicine: a person could be emotionally and psychologically evaluated by their level of fluids. According to ancient Greek Humorism, the traditional four temperaments—sanguine, melancholic, choleric, and phlegmatic—were caused by imbalances in the four bodily fluids (humors): black bile, yellow bile, phlegm, and blood.
Sanguine: Too much blood – Passionate, Bold, impulsive
Melancholic: Too much black bile – Depressed, anxious, moody
Choleric: Too much yellow bile – Irritable, hostile, bitter
Phlegmatic: Too much phlegm – Passive, introverted, rational
This intrigue led her to create ‘The Four Humors’.