(Πραξαγόρας), a celebrated physician, who was a native of the island of Cos. (Galen, de Uteri Dissect. 100.10, vol. ii. p. 905, et alibi.)
His father's name was Nicarchus [*](* As the word νεῦρον sometimes signifies a ligament, as well as a nerve, in the ancient writers (see note to the Oxford edition of Theophilus de Corp. Hum. Fabr. p. 204, 1. 5), Sprengel and others have supposed that the word bears this meaning in the passage referred to, but Kühn,with more probability considers that the more common signification of the word is the true one (Opusc. vol. ii. p. 140).) (Galen, loco cit.; de Facult. Nat. 2.9, vol. ii. p. 141, de Tremore, 100.1, vol. vii. p. 584), and he belonged to the family of the Asclepiadae (id. de Meth. Med. 1.3, vol. x. p. 28). He was the tutor of Philotimus (id. loco cit.; de Aliment. Facult. 1.12, vol. vi. p. 509), Plistunicus (Cels. de Med. i. praef. p. 6), and Herophilus (Galen, de Differ. Puls. 4.3, vol. viii. p. 723, de Meth. Med. 1.3, vol. x. p. 28, de Tremore, 100.1, vol. vii. p. 585); and as he was a contemporary of Chrysippus, and lived shortly after Diocles Carystius (Cels. de Med. i. praef., p. 5; Pliny, H. N., 26.6), he may be safely placed in the fourth century B. C. He belonged to the medical sect of the Dogmatici (Galen, Introd. 100.4, vol. xiv. p. 683), and was celebrated for his knowledge of medical science in general, and especially for his attainments in anatomy and physiology. He was one of the chief defenders of the humoral pathology, who placed the seat of all diseases in the humours of the body (id. ibid. 100.9, p. 699). He is supposed by Sprengel (Hist. de la Méd., vol. i. p. 422, 3), Hecker (Gesch. der Heilk. vol. i. p. 219), and others, to have been the first person who pointed out the distinction between the veins and the arteries; but this idea is controverted (and apparently with success) by M. Littre (Œuvres d' Hippocr. vol. i. p. 202, &c.), who shows that the distinction in question is alluded to by Aristotle (if the treatise de Spiritu be genuine), Hippocrates (or at least the author of the treatise de Articulis, who was anterior to Praxagoras), Diogenes Apolloniates, and Euryphon. Many of his anatomical opinions have been preserved, which show that he was in advance of his contemporaries in this branch of medical knowledge. On the other hand, several curious and capital errors have been attributed to him, as, for instance, that the heart was the source of the nerves (an opinion which he held with Aristotle), and that the ramifications of the artery, which he saw issue from the heart, were ultimately converted into nerves, as they contracted in diameter (Galen, de Hippocr et Plat. Decr. 1.6, vol. v. p. 187). [*](* In Galen, Comment. in Hippocr. "Aphor." 1.12, vol. xvii. pt. ii. p. 400. Νικάνδρου must be a mistake for Νικάρχου. In some modern works his father is called Nearchus, but perhaps without any ancient authority.) Some parts of his medical practice appear to have been very bold, as, for instance, his venturing, in cases of ileus when attended with introsusception, to open the abdomen in order to replace the intestine (Cael. Aurel. de Morb. Acut. 3.17, p. 244).
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