Leonid Zhmud The Origin of the History of Science in Classical Antiquity

particular stress on what distinguished it from the ‘normal’ geocentric theory:
in the center of Philolaus’ cosmos there is the central fire (Hestia), around
which all the heavenly bodies revolve, including the earth and the counter-
earth. If Philolaus stands behind Eudemus’ Pythagoreans, we have to infer that
Eudemus separated the ‘correct’ part of Philolaus’ system (the moon, the sun,
and the five planets) from the ‘erroneous’ one (Hestia, the moving earth, and
the counter-earth) and (contrary to Aristotle’s criticism) decided to ignore the
second and to regard the first as a discovery, which he attributed to Philolaus
without mentioning him by name. This implication is obviously too heavy for
the hypothesis to sustain.
Not a single ancient source states that Philolaus discovered the ‘correct’
order – and with good reason, because he did not. Nor could Eudemus believe
that he did. Philolaus’ innovations – Hestia, the counter-earth, the earth’s ro-
tation around Hestia – can only be understood as a modification of an earlier
system in which the moon, the sun, the five planets, and the stars revolved
around the earth.
128
This is what Eudemus understood to be the ‘correct’ order.
The Pythagoreans who discovered it must have lived before Philolaus.
129
Most
likely, Eudemus referred to the Pythagoreans ‘in general’ when he could not
adduce any particular name of the
pro¯tos heurete¯s. In the History of Geometry,
such references are related to the Pythagoreans of the first half of the fifth cen-
tury in connection with, for example, the theorem of the sum of the angles of a
xography does not give the order of the five planets in Philolaus, its very silence tes-
tifies to this order having been the ‘normal’ one (Boll. Hebdomas, 2566; Burkert.
L & S, 313).
127
Cael. 293a 18-b 30, Met. 986a 10f. See Zhmud. Wissenschaft, 268ff.
128
Zhmud. Philolaus, 249f. Democritus’ system seems to present a similar modifica-
tion: the moon, Venus, the sun, other planets, the stars (68 A 86). Democritus studied
with the Pythagoreans (A 1, 38) and must have known their mathematics (see above,
202 n. 162).
129
Interestingly, Burkert,
L & S, 313f., who identified Eudemus’ ‘Pythagoreans’ with
Philolaus, was far from regarding the latter as the author of the ‘correct order’. In-
stead, he postulated the existence of a common source for Philolaus and Democritus
and connected it with the borrowing of the Babylonian data on planets that took
place in the time between Anaxagoras and Philolaus. Meanwhile, the Greek order of
planets has nothing in common with the Babylonian one, which was never based on
the periods of the planets’ revolution around the earth. The order accepted in Baby-
lonian astronomy of the fifth century was the following: Jupiter, Venus, Saturn, Mer-
cury, Mars; later it was replaced with a slightly different one: Jupiter, Venus, Mer-
cury, Saturn, Mars (Neugebauer.
HAMA II, 690).

---

4. Anaxagoras. The Pythagoreans
259
triangle or the theory of the application of areas (fr. 136–137).
130
These parallels
also point to Anaxagoras’ contemporaries, rather then to the generation of Phi-
lolaus.
It has to be pointed out that the order of the heavenly bodies as well as their
distances from the earth depend on the velocity (i.e., the period) of their revol-
ution around the earth. In the last third of the fifth century, these problems be-
came part of the standard course in astronomy. According to Xenophon, So-
crates, while encouraging his students to familiarize themselves with practical
astronomy, “strongly deprecated studying astronomy so far as to include the
knowledge of heavenly bodies revolving on different orbits, and of planets and
comets, and wearing oneself out with the calculations of their distances from
the earth, their periods of revolution and the causes of these”.
131
Though he had
attended lectures on these subjects himself, Socrates believed that one could
waste one’s whole life on them, denying to oneself many important things. A
similar notion of astronomy is found in Plato’s