The First of All Natural Sciences: Roger Bacon on Perspectiva and Human Knowledge

Abstract

This article is devoted to Roger Bacon’s understanding of perspectiva as “the first of all natural sciences.” After considering a few alternative medieval definitions and classifications of this discipline – such as al-Fārābī’s, Grosseteste’s and Kilwardby’s – the author turns to Bacon’s arguments for according to perspectiva so exceptional a role. He shows that Bacon’s arguments are grounded in his peculiar understanding of the visual process: according to Bacon, vision is indeed the only sense in which perception takes place “by reasoning” (per sillogismum). The author argues that this theory of perception also lays the foundations for Bacon’s – prima facie amiss – claim that “concerning vision alone, and no other sense, have philosophers developed a separate science.” The author explores this point by contrasting with one another Bacon’s conception of perspectiva and of music, and closes with some more general remarks on the implications of Bacon’s account of the visual process for his theory of knowledge. Based on his theory of a “vision by reasoning,” the author concludes that Bacon came to reinterpret perspectiva as the organon of visual knowledge.