Introduction

Already by the Roman Imperial period (1st–3rd century), the Data had begun to lead a double life. Originally composed, or arranged, by Euclid (early-3rd century BCE) as a purely geometrical text for use in geometrical analysis, in the late Hellenistic (3rd– 1st centuries) and early Imperial periods, mathematicians began to repurpose this work, and by the time of Heron (probably mid-1st century CE) and Ptolemy (mid-2nd century CE), it appears to have been used as a means to justify computational procedures. By the Late-ancient period (3rd–6th century), it was used as a foundational text in both of these, rather different, areas by scholars and teachers such as Pappus (early-4th century CE) and Theon of Alexandria (late-4th century CE).