Eudemus of Rhodes () was an ancient Greek philosopher, considered the first historian of science, who lived from c. 370 BCE until c. 300 BCE. He was one of Aristotle's most important pupils, editing his teacher's work and making it more easily accessible. Eudemus' nephew, Pasicles, was also credited with editing Aristotle's works. Life Eudemus was born on the isle of Rhodes, but spent a large part of his life in Athens, where he studied philosophy at Aristotle's Peripatetic School. Eudemus's collaboration with Aristotle was long-lasting and close, and he was generally considered to be one of Aristotle's most brilliant pupils: he and Theophrastus of Lesbos were regularly called not Aristotle's "disciples", but his "companions" (ἑταῖροι). It seems that Theophrastus was the greater genius of the two, continuing Aristotle's studies in a wide range of areas. Although Eudemus too conducted original research, his forte lay in systematizing Aristotle's philosophical legacy, and in a clever didactical presentation of his teacher's ideas. Later authors who wrote commentaries on Aristotle often made good use of Eudemus's preliminary work. It is for this reason that, though Eudemus's writings themselves are not extant, we know many citations and testimonia regarding his work, and are thus able to build up a picture of him and his work. Aristotle, shortly before his death in 322 BC, designated Theophrastus to be his successor as head of the Peripatetic School. Eudemus then returned to Rhodes, where he founded his own philosophical school, continued his own philosophical research, and went on editing Aristotle's work. Historian of science At the insistence of Aristotle, Eudemus wrote histories of Greek mathematics and astronomy. Though only fragments of these have survived, included in the works of later authors, their value is immense. It is only because later authors used Eudemus's writings that we still are informed about the early history and development of Greek science. In his historical writings Eudemus showed how the purely practically oriented knowledge and skills that earlier peoples such as the Egyptians and the Babylonians had known, were by the Greeks given a theoretical basis, and built into a coherent and comprehensive philosophical building. As regards his History of Arithmetics (Άριθμητικὴ ἱστορία) we only have the tiniest bit of information: there is only one testimonium, saying that Eudemus mentions the discovery by the Pythagoreans that it is possible to connect musical intervals with integer numbers. Eudemus's History of Geometry (Γεωμετρικὴ