Aristotle. Later commentaries on the Physics (517) and the Meteorologica (after 529),
however, display a marked shift toward a more critical approach to Aristotelian physics.
Philoponos considers void space a theoretical possibility. He proposes an alternative to
Aristotelian forced motion, suggesting an impetus force is somehow imparted to the
moved thing by the mover. In the De opificio mundi (1.12, pp. 28–29 Reichardt), Philoponos
even suggests God placed an impetus force in the heavens at creation. Most Christian
natural philosophers denied the heavens a divine status and Philoponos also denied them
a soul, so a primitive impetus theory could provide a natural – as opposed to a supernatural
or psychic – explanation for their motion. He also refines the concepts of prime matter
and place.
His best known and most widely influential contributions to natural philosophy were his
arguments against eternity. The extent of these polemics is quite broad. All arguments in
defense of eternity are attacked in detail, and, while some of these have little philosophical
force on their own, as a whole the polemics make for a compelling dossier against the
philosophical case for eternity. Moreover, some of his arguments are quite novel and power-
ful, particularly those using puzzles about infinity. Their effectiveness is evident in S-
’ response in his commentary on the De caelo. He attacks not only the arguments, but
also Philoponos’ character and his Christianity. Nonetheless, Philoponos’ arguments against
eternity spread widely, particularly in the Islamic Middle Ages, and subsequently in the
Latin West.
While the anti-eternity polemics are primarily a negative critique, Philoponos’ final nat-
ural philosophical work aimed to construct a Christian natural philosophy through a literal
reading of Genesis. The De opificio mundi, primarily striving to reconcile Moses’ account with
Greek science, was written in response to anti-pagan Christian natural philosophers,
such as K I, whose Topographia Christiana ridiculed Christians who
failed to abandon Greek philosophy when they forsook pagan religion. Philoponos’ reply
shows that Greek rationalism is not only useful for Christians but necessary. Moreover, he
argues that the Genesis narrative prefigures and even influences later Greek cosmology. The
main points of contention between Kosma ̄s and Philoponos focus on the shape of the
world, the materiality of angels and the anthropology implied by being made in the image
of God.
Ed.: H. Hase, De usu astrolabii eiusque constructione (1839); R. Hoche, Eis to pro ̄ton [kai deuteron] te ̄s
Nikomakhou Arithme ̄tike ̄s eisago ̄ge ̄s (1864); CAG 13 – 17 (1887–1909); H. Rabe, De aeternitate mundi (1890);
G. Reichardt, De opificio mundi libri VII (1897); R. Sorabji, ed., ACA (1987–); C. Scholten, trans., De
opificio mundi (1997).
RE 9.2 (1916) 1764–1795 (#21), W. Kroll; DSB 7.134–139, S. Sambursky; R. Sorabji, ed., Philoponus
and the Rejection of Aristotelian Science (1987); REP 7.371–378, C. Wildberg; BNP 11 (2007) 89–91,
K. Savvidis and C. Wildberg; NDSB 4.51–52, Carl Pearson.
Carl Pearson
Io ̄anne ̄s of Antioch, arkhiatros (1200 – 1500 CE?)
A collection of compound medicines is preserved under the name of a Io ̄anne ̄s of Antioch
in a Byzantine manuscript now in Paris, BNF, graecus 2315 partially copied by Zakharias
Kallierge ̄s (d. after 1524). The texts in the manuscript seem to reproduce a collection cre-
ated in a late Byzantine hospital, perhaps in Constantinople, as they include the Byzantine
translation of Avicenna’s De pulsibus (ca 1000) and other treatises circulating among
IO ̄ANNE ̄S OF ANTIOCH, ARKHIATROS