This book describes the role played by the liver in Antiquity as the main viscus of the body, the vital organ, bearing all forms of mental and emotional activity (“the seat of the soul”) and its function as the primary organ used for divination. Contrary to what happened in the past, the liver is no longer linked to feelings – a notion now connected to the heart. Current knowledge describes the liver as a massy, solid organ, involved in metabolism, bile production, and glucose storage. This book follows the historical body of evidence on the central role of the liver up to the beginning of the Modern Era, investigating how and when these major paradigm shifts occurred, and which traceable elements of this tradition persists to this day. Antiquity was the apogee of the biggest organ in the human body. Through divination, Medicine, Religion and cultural representation, the organ exercised millenary hegemony within the most important human civilizations. The liver has gone through a long, dynamic process in its quest for a place in the human mind. This process is reflected across disciplines and pervades different areas. The historical tracking of the liver history through the surviving documentation has a crucial role in the History of Medical knowledge.