Diocles Carystius
Διοκλῆς ὁ Καρύστιος
(Διοκλῆς ὁ Καρύστιος), a very celebrated Greek physician, was born at Carystus in Euboea, and lived in the fourth century B. C., not long after the time of Hippocrates, to whom Pliny says he was next in age and fame. (H. N. 26.6.) He belonged to the medical sect of the Dogmatici (Gal. de Aliment. Facult. 1.1, vol. vi. p. 455).
Some persons have attributed to Diocles the honour of first explaining the difference between the veins and arteries; but this does not seem to be correct, nor is any great discovery connected with his name.
Works
Diocles wrote several medical works, of which only the titles and some fragments remain, preserved by Galen, Caelius Aurelianus, Oribasius, and other ancient writers.
Letter to King Antigonus
The longest of these fragments is a letter to king Antigonus, entitled Ἐπιστολὴ Προφυλακτική, A Letter on Preserving Health, which is inserted by Paulus Aegineta at the end of the first book of his medical work, and which, if genuine, was probably addressed to Antigonus Gonatas, king of Macedonia, who died B. C. 239, at the age of eighty, after a reign of forty-four years. It resembles in its subject matter several other similar letters ascribed to Hippocrates (see Ermerins, Anecd. Med. Graeca, praef. p. xiv.), and treats of the diet fitted for the different seasons of the year.
Editions
It is published in the various editions of Paulus Aegineta, and also in several other works: e. g. in Greek in Matthaei's edition of Rufus Ephesius, Mosquae, 1806, 8vo.; in Greek and Latin in the twelfth volume of the old edition of Fabricius, Biblioth. Graeca; and in Mich. Neander's Syllogae Physicae, Lips. 1591, 8vo.; and in Latin with Alexander Trallianus, Basil. 1541, fol.; and Meletius, Venet. 1552, 4to. &c.
Translation
There is also a German translation by Hieronymus Bock, in J. Dryander's Practicirbüchlein, Frankfort, 1551, 8vo.
Further Information
Further information respecting him may be found in the different histories of medicine, and also in Fabricius, Biblioth. Graeca, vol. xii. p. 584, ed. vet.; A. Rivinus, Programma de Diode Carystio, Lips. 1655, 4to.; C. G. Gruner, Bibliothek der Alten Aerzte, Leipz. 1781, 8vo. vol. ii. p. 605; C. G. Kühn, Opuscula Academ. Med. et Philolog. Lips. 1827, 8vo. vol. ii. p. 87. In these works are quoted most of the passages in ancient authors referring to Diocles; he is also mentioned by Soranus, de Arte Obstetr. pp. 15, 16, 67, 99, 124, 210, 257, 265; and in Cramer's Anecd. Graeca Paris. vol. i. p. 394, and vol. iv. p. 196.
From William Smith (ed.), Dictionary of Greek and Roman Biography and Mythology. Text provided under a CC BY-SA license by Perseus Digital Library, http://www.perseus.tufts.edu, with funding from the National Endowment for the Humanities and Tufts University. Data accessed from https://github.com/PerseusDL/canonical-pdlrefwk/ on 17 October 2026.