Eudemus of Rhodes - Historian of Science

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 ἱστορία) is mentioned by many more writers, including Proclus, Simplicius, and Pappus of Alexandria. From them we know that the book treated the work by, among others, Thales of Miletus, the Pythagoreans, Oenopides of Chios, and Hippocrates of Chios. Among the topics Eudemus discussed were the discovery of geometrical theorems and constructions (systematized in Eudemus's days by Euclid in his Elements), and the classical problems of Greek geometry, such as the quadrature of the circle and the duplication of the cube.

• We know quite a lot too about Eudemus's History of Astronomy (Άστρολογικὴ ἱστορία), from sources such as Theon of Smyrna, Simplicius, Diogenes Laërtius, Clement of Alexandria, and others. Building upon those data we can reconstruct with some accuracy the astronomical discoveries that were made in Greece between 600 and 350 BC, as well as the theories that were developed in that period regarding the earth, solar and lunar eclipses, the movements of the heavenly bodies, etcetera. Philosophers and astronomers treated by Eudemus include Thales, Anaximander, Anaximenes, Oenopides, Eudoxus, and others.

Two other historical works are attributed to Eudemus, but here his authorship is not certain. First, he is said to have written a History of Theology, that discussed the Babylonian, Egyptian, and Greek ideas regarding the origins of the universe. Secondly, he is said to have been the author of a History of Lindos (Lindos is a port on Rhodes).

To Eudemus is also ascribed a book with miraculous stories about animals and their humanlike properties (exemplary braveness, ethical sensitivity, and the like). However, as the character of this work does not at all fit in with the serious scientific approach that is apparent from Eudemus's other works, it is generally held that Eudemus of Rhodes cannot have been the author of this book (it may have been another Eudemus—Eudemus was a fairly common name in ancient Greece).