by the skepticism of the Hellenistic Academy and especially by the fallibilism character-
izing its final phase. Any enquiry into the physical world and its physical causes can merely
attain probability (cf. De def. or. 435E–436A; Ti. 68e–69a; Phaed. 97b–99d). The philosopher,
however, should also look for final, i.e. teleological, causes. The fallible character of any
inquiry on the level of material causes enables Plutarch to give serious consideration
not only to Plato’s views, but also to physical doctrines of the Peripatetic, Stoic and
Epicurean schools. Even if their specific doctrines find provisional acceptance, they
remain subordinated to Plutarch’s overall Platonism.
In De facie in orbe lunae, Plutarch, citing H and A, discusses
astronomy, geography, and catoptrics. Lunar phenomena, Plutarch argues, show that the
Moon’s constitution is earthy. He mentions the theory that the Moon’s velocity prevents it
from falling, rejects the Aristotelian doctrine of natural motion, discusses distances between
heavenly bodies, size, position and shape of the Earth, the existence of the “antipodes,”
lunar phases, solar and lunar eclipses, the habitability of the Moon, lunar vegetation, the
apparent face in the Moon (the great ocean reflected in the Moon, according to an
Aristotelian speaker). In the introduction to the concluding myth a trans-Atlantic continent
and islands westward of Britain are mentioned. Plutarch rejects motion of the Earth
(Quaestiones Platonicae 1006C–E; citing Aristarkhos, S, T). He also
treats the parts of speech (1009B–1011E), and antiperistasis, a Platonic theory to explain the
properties of magnets and amber, the motion of projectiles and thunderbolts, the working of
cupping-instruments, the perception of consonance (1004D–1006B; cf. Ti. 79e–80c). In
De animae procreatione, Plutarch discusses arithmetical problems related to Plato’s harmonic
division of the soul. In Quaestiones naturales, he discusses various issues, including agriculture,
zoology, medicine, meteorology, fishing, hunting, cooking, properties of sea water, many pre-
viously addressed by A or Theophrastos or “Laitos” ( probably O L).
Plutarch often offers original solutions, probably of his own making. Quaestiones Convivales
address medicine, botany, zoology, physics in general, and astronomy. Plutarch considers
comparable subjects in some of the fragments of his commentaries on H (fr.127),
H (fr.75–76, 80–81, 102, 104) and N’ The ̄riaka (fr.113–114). The scholia
(fr.13–20) preserve excerpts from notes on A’ Diosemiae. In De primo frigido, Plutarch
searches for the primarily cold element: not air (the Stoics), not water (E,
S L), but earth. The essay closes with an appeal to suspend judgment.
In De sollertia animalium and Bruta animalia ratione uti, Plutarch upholds the intelligence of
animals against the Stoics. De tuenda sanitate praecepta provides dietary advice.
Plutarch occasionally addresses scientific theories in the anti-Stoic works De Stoicorum
repugnantiis (rejecting the Stoic view on the role of air in the animation of the fetus, and of
air as primarily cold: 41–43), and De communibus notitiis (on mixture, the divisibility of body,
the continuum, the structure of matter: 37–43; 49–50). Plutarch inserts a treatment of the
Stoic hypothetical syllogism and speculations on the number five in De E Delphico. De Pythiae
oraculis opens by discussing the atmospheric conditions in Delphi giving bronze a peculiar
patina and then moves on to exhalations as material causes for the oracle. This issue also
features in De defectu oraculorum, which, moreover, describes the lamps at the shrine of
Ammo ̄n consuming less and less olive oil every year (410B).
The handbook On music and the geographical work On rivers (De fluuiis) are spurious: see
the next two entries.
RE 21.1 (1951) 636–962, K. Ziegler; P.L. Donini, “Science and metaphysics. Platonism, Aristotelian-
ism, and Stoicism in Plutarch’s On the face in the moon,” J.M. Dillon and A.A. Long, edd., The Question
PLUTARCH OF KHAIRO ̄NEIA, L. MESTRIUS