What We Can Learn from a Diagram: The Case of Aristarchus's On The Sizes and Distances of the Sun and Moon

By using the example of a single proposition and its diagrams, this paper makes explicit a number of the processes in effect in the textual transmission of works in the exact sciences of the ancient and medieval periods. By examining the diagrams of proposition 13 as they appear in the Greek, Arabic, and Latin traditions of Aristarchus's On the Sizes and Distances of the Sun and Moon, we can see a number of ways in which medieval, and early modern, scholars interpreted their sources in an effort to understand and transmit canonical ancient texts. This study highlights the need for modern scholars to take into consideration all aspects of the medieval transmission in our efforts to understand ancient practices.