The sacred paleo medicine with superstitions and religious ceremonies, applied by shamans and magicians, not only in its organization but also in its therapeutic approach and its interpretative method was the first step for the therapy of mental illnesses. It was part of a mythological system, and its representatives were doctor-priests, who, slowly at the same time, collected clinical and semantic data, paving the way before Hippocrates. To investigate the evolution of such thoughts we extracted data from electronic data banks and ancient books from both public libraries and private collections. The texts of ancient medicine cover an extended period ranging from the “Iππoκρατικό Σώμα” (Corpus Hippocraticum) of the classical period (V-IV century BC) up to the authors of the late classical ages Roman Empire such as e.g., Aretaeus, Celsus, Galen, and others. This work aims to take a journey through the legacy of ancient Greek philosophy concerning the psyche that influenced medicine in Roman Classical age in its diagnosis and therapy for the mentally ill, thus laying the scientific foundations of modern neuropsychiatry.