The Internal Senses in Nemesius, Plotinus and Galen: the Beginning of an Idea

This study traces the notion of the internal senses in three ancient authors, namely Nemesius, Plotinus and Galen. It begins with Nemesius, and then by going backward ends with Galen. The textual evidence investigated in this study shows clearly that Galen, after acknowledging the Platonic tripartite soul, locates the various dunameis of the soul in the brain. The “localization” theory of Galen plays a crucial role in paving the way for the foundation of the internal senses, which both Plotinus and Nemesius adapted. Just as with the external senses one can locate various sense-organs in different parts of the body, viz., touch, smell, sight etc., so too with the internal senses, thanks to Galen, one is able to locate them in various organs of the body. Thus philosophers are able to explain the role of all these different (internal) senses in their account of sense-perception.