Ed.: U.C. Bussemaker, Poetae Bucolici et Didactici (1862) 132–134.
PTK
P ⇒ P
Praxagoras of Ko ̄s (325 – 275 BCE)
Greek physician, from a highly reputed medical family of the Asclepiad tradition active in
Ko ̄s (including his father Nikarkhos and an earlier Praxagoras, pupil of H). His
pupils included H, P, P and X. His name is
mentioned for an ointment in a papyrus of ca 250 BCE (SB 9859d). G, citing him
frequently with D as an important member of the Dogmatic medical tradition,
dates him a little after Hippokrate ̄s (Tremor Palp. 7.584 K., Diff. Puls. 4.3 [8.723 K.]). A more
ancient tradition credits Praxagoras, together with Hippokrate ̄s and K
K (), with perfecting dietetics (Schol. Hom. Iliad. 11.515).
He is credited with many treatises, revealing the broad spectrum of his medical activity,
some surviving to Gale ̄n’s era (Gale ̄n wrote a polemical essay against Praxagoras’ humoral
doctrine). Praxagoras wrote on physiology and anatomy (Phusika, at least two books, and
Anatomy apparently in many books), as well as on pathology (On diseases, at least three books,
and On differences in acute diseases), prognosis (On the concurrent signs, two books, and On the
supervening affections [or signs]), and therapy (Ways of therapy, four books, and Causes, affections
and therapies).
Having developed and expanded “Hippokratic” humoral physiology and pathology,
Praxagoras probably also wrote a treatise on humors, wherein he distinguished ten
humors (the most-often cited among them being the “glassy” one, hualodes) plus blood.
Distinguishing some as kinds of phlegm, others according to taste, consistency or quality, he
claimed they are formed in the veins by nutriment transformed by heat, determining health
and disease (Gale ̄n Sympt. Caus. 1.6, 1.7 [7.124, 137 K.], -G, I 9
[14.698–699 K.]). Fever, for example, is caused by the putrefaction of humors (MM 2.4.13
[10.101 K. = p. 51 Hankinson).
Praxagoras was apparently the first to distinguish the anatomical structure and physio-
logical function of veins and arteries. Veins contain blood, and arteries air (pneuma) intro-
duced through respiration (and from gaseous digestive byproducts) and nourishing the soul.
He places the seat of the soul in the heart, thus making it the he ̄gemonikon, arguing that
the brain is just an extension of the spinal marrow. Praxagoras did not believe in innate
heat, but thought that bodily heat was drawn in from the outside. No details of his theory of
digestion remain, but he thought that blood was the product of good digestion, becoming
flesh through the veins. (It is wrong to ascribe to Praxagoras the theory of his pupil
Pleistonikos that digestion is a process of putrefaction, sepsis: C 1.pr.20). He surely
shared with his pupils the idea that sperm comes not only from the brain but from the entire
body (-G, D 19.449 K.), and asserted the filtering role of kidneys
(Gale ̄n Nat. Fac. 1.13 [2.30 K.]). His anatomical doctrines (that arteries become more and
more subtle finishing as nerves, and pulse independently of the heart) are sometimes criti-
cized by Gale ̄n. Regarding therapy, he approved bloodletting, used emetics, and discussed
the utility of fasting. Many of his opinions and treatments of single diseases are preserved
by the P and in C A, while Athe ̄naios (Deipn. 2 [32d,
41a, 46d], 3 [81c]) records some of his opinions in the use of wine, water and other foods, a
field that Praxagoras and his school explored in detail.
PRAXAGORAS OF KO ̄S