Ptolemy on Visual Properties

How do the essences of objects relate to the objects’ being shaped or figured? To shed a light upon this issue, in my project I will reconstruct ancient views on how we cognize objects through encountering lines, figures, and shapes. The primary source for my research is Proclus’ Commentary to the First Book of Euclid’s “Elements”. To identify the major sources for Proclus’ account, I will also consider the works of Plato and Aristotle, and search for alternative theories in Euclid’s and Ptolemy’s treatises on optics. During the 2014/2015 academic year I mainly intend to elaborate my project proposal.