Which body humor is linked to a lethargic personality?

The body humor linked to a lethargic personality is phlegm. In ancient Greek medicine, particularly in the theory of the four humors, phlegm was associated with a calm, sluggish, and lethargic temperament. Individuals influenced by this humor were thought to exhibit traits such as being relaxed, easy-going, and sometimes excessively passive or indifferent.

This concept stems from the belief that an imbalance in phlegm could lead to a lack of motivation and energy, contributing to a personality that is less driven and more lethargic. This correlation continued to be referenced in discussions of personality types in both classical antiquity and into later historical periods, where the humoral theory was a dominant framework for understanding human behavior and health.

In contrast, the other humors—blood, yellow bile, and black bile—are associated with different personality traits. Blood is often linked to a sociable and lively disposition, yellow bile to a more aggressive and irritable nature, and black bile to melancholic and reflective tendencies. Understanding these associations helps provide insight into the historical context of personality theories and how they have evolved over time.