Plotinus on Starting-Points of Reasoning

Plotinus treats certain pre-philosophical concepts as reliable or promising starting-points for philosophical study. This article studies the way in which he, in the act of philosophizing, conceives of the passage from an unclear understanding, a kind of pre-concept, to a better, philosophical conception. What are the sources of this passage? What is the role of data given by sense-perception? In what way are innate conceptual and cognitive capacities involved? It will be argued that the methodology suggested is a Platonic version of the Stoic appeal to common notions (koinai ennoia). Moreover, Plotinus seems to maintain several features of the empirical original. The concepts discussed are not primarily introspected or intuited, but seem to result from both experience and from innate tendencies. The bottom-up approach of scrutinizing the combination of inquiries in the Enneads (and in a commentary of Proclus) and the methodological remarks made within these same inquiries, exposes, further, an interesting list of concepts significant for the Neoplatonic theory-building : freedom, oneness, time and eternity, as well as good and evil