Gregg De Young

The first part of the paper describes the Persian translation of Naṣīr al-Dīn al-Ṭūsī’s Taḥrīr Kitāb Uqlīdis by Quṭb al-Dīn al-Shīrāzī, with a primary focus on his appendix to book i. Part of a larger encyclopedic collection, al-Shīrāzī’s translation continued to be read for centuries. As evidence of the work’s influence, al-Shīrāzī’s appendix to book i was included in a nineteenth century printed edition of Muḥammad Barakat’s commentary on book i of al-Ṭūsī’s treatise. I discuss this later use of al-Shīrāzī’s appendix in the second part of the paper.

During the third/ninth century, several commentators on Euclid’s Elements composed blocks of propositions (called ziyadat) in which they expanded specific concepts or techniques beyond the basic discussions of Euclid. Among the earliest of these ziy?d?t were three propositions created by al-‘Abbas b. Sa‘?d al-Jawhar? in an attempt to demonstrate the validity of Euclid’s definitions V, 5 and V, 7. A unique manuscript of a Persian translation of these propositions has recently been discovered. In this paper, I introduce this Persian text, offer an English translation, and discuss the relationship between the Persian and Arabic versions.