Geo ̄rgios of Pisidia (ca 610 – ca 634 CE)
Born ca 580, deacon and archivist of Saint-Sophia, a remarkable and admired poet, wrote
various historical works and a long elaborate poem (1,910 trochaic trimeters) on the cre-
ation: Hexaemeron (or Kosmourgia; after 630). Following the hexaemeronic tradition (see B,
G N, E, and P A, de opificio mundi), in this
apologetic and lyrical poem, Geo ̄rgios develops relevant observations on natural history in a
clear and classical style, juxtaposing biblical tradition with “pagan” sciences, emphasizing
Stoic themes such as the animated kosmos and universal sympathy (lines 1397, 1679).
Especially influenced by the two Kappadokians Gregory and Basil, he treats with erudition,
but loosely ordered, questions of astronomy, human anatomy and psychology, and pharma-
cology, sometimes degenerating to popular marvels (such as vulture parthenogenesis: 1136–
1153). In the pharmacological sections (lines 636–680, 1353–1440, 1512–1624) his medical
terminology is rich ( probably from a handbook, and partly directly from G). He men-
tions the silkworm (sko ̄lex Seriko ̄n: i.e., bombyx mori), introduced to Constantinople (ca 554),
producing unworthy clothes, but proof of the resurrection (lines 1293–1302).
Ed.: PG 92.1425–1580.
G. Bianchi, “Note sulla Cultura a Bisanzio all’Inizio del VII secolo in Rapporto all Esamerone di Giorgio
di Pisidia,” Rivista di studi bizantini e neoellenici 2 – 3 (1965–1966) 137–143; HLB 2.269–270; BNP 5
(2004) 788 (#6), I. Vassis.
Arnaud Zucker
G ⇒ G. I C
Gessios of Petra (475 – 520 CE?)
Greek physician active in Alexandria where he studied and then taught medicine, with
I A seemingly among his students. A highly praised medical teacher
(iatrosophiste ̄s), Gessios commented on the H C (e.g. De natura pueri) and
perhaps also Gale ̄nic treatises, e.g. De sectis (Latin translations of commentaries attributed in
most MSS to Io ̄anne ̄s of Alexandria or A R are credited to Gessios
in MS Città del Vaticano, Biblioteca Apostolica Vaticana, Palatinus latinus 1090). In Arabic
sources, Gessios is considered creator of the Summaria Alexandrinorum, a collection of 16
Gale ̄nic treatises with commentary, constituting the basis of late-Alexandrian and Arab
medical teaching, and whose interpretation is still disputed. Gessios was forcedly converted
to Christianity by the Byzantine emperor Ze ̄no ̄n (474–491) and baptized. Nevertheless, he
also received “extraordinary honors” from the emperor, as well as large amounts of money.
Sophronios ( possibly the patriarch of Jerusalem, 630–638) in his account of the therapeutic
miracles performed by Holy Healers (miracle 30 [302–306 Fernandez Marcos]) reports that
Gessios, a known pagan, denied that the Holy Healers Kuros (Cyrus) and Io ̄anne ̄s (vener-
ated in Menuthis, near Alexandria) obtained their knowledge of medicine directly from
God as according to legend, for their therapeutic methods and treatments were strictly
Hippokratic. In punishment, his back and neck were paralyzed, and all “pagan” medicine
(Hippokratic and Gale ̄nic) failed to cure Gessios, who was then forced to seek a cure from
the Saints.
Ed.: C.D. Pritchet, Iohannis Alexandrini commentaria in libru De sectis Galeni. Recognovit et adnotatione critica
instruxit (1982); N. Palmieri, L’antica versione latina del «De sectis» di Galeno (Pal. lat. 1090) (1989).
GESSIOS OF PETRA