Why was the liver considered important in Mesopotamian and Etruscan divination?

In Mesopotamian and Etruscan religious traditions, the liver was considered a vital focal point for divination because it was believed to be the seat of life and affectivity.12

In Mesopotamian religion, practitioners did not approach anatomy through modern physiological study; instead, they viewed organs as the centers of specific emotions and mental faculties. The liver was specifically identified as the seat of affectivity, making it a primary vessel for understanding divine will.2

For the Etruscans, the practice of haruspicy—or hepatoscopy—was central to their religious life. They operated on the principle that the macrocosm of the heavens was reflected in the microcosm of the earth and the viscera of sacrificial animals. The liver was viewed as a map of the divine realm; for example, the famous bronze model of a sheep's liver found in Piacenza displays divisions that correspond to the celestial compartments inhabited by various deities. By examining the liver, diviners believed they could interpret the intentions and manifestations of the gods, which was essential for guiding both public and private actions.34