τῷ ὄντι δὴ κτλ.
It has been conjectured by Brandt (
z. Entw. d. plat. Lehr. v. d. Seelenteilen p. 8) that Plato is thinking of Eudoxus; but there is nothing to suggest a specific reference here, as there was in 528 B, C, and as Eudoxus, “the father of scientific astronomical observation in Greece” was preeminently “a practical observer” (Allman
Gk. Geometry etc. p. 142), he would hardly be described by Plato in this passage as
τῷ ὄντι ἀστρονομικός. See also Hirmer
Entst. u. Komp. d. plat. Pol. p. 667.
τὰ τοιαῦτα
: i.e.
ὁρατά, σωματοειδῆ.
τῷ τοῦ οὐρανοῦ δημιουργῷ
: the Demiurgus of the
Timaeus.
τὴν δὲ νυκτὸς κτλ.
: with which astronomical observation is concerned. Plato's tone is very different in the
Timaeus (47 A ff.) as Grote points out (
Plato III p. 235 note, where also an amusing parallel is quoted from Malebranche); but it should be remembered that it is with the educational value of astronomy as a preparation for Dialectic that we are here concerned (note
εἰ μέλλομεν—ποιήσειν in B, and see App. II).
τῶν ἄλλων ἄστρων
: ‘the other stars’ (Schneider), as
ταῦτα shews, not ‘the stars besides’ (as Stallbaum).
ταῦτα
: viz. the Sun and Moon, which make day, night, year, and month.
παραλλάττειν ‐‐ ὁρώμενα
is a cardinal principle with Plato: see
Tim. 28 A
, B, 37 D and especially
Pol. 269 D
, E.
παράλλαξις is used half-technically of any change or deviation in the courses of the heavenly bodies, as for example in the legend of Atreus (
Pol. 269 A
): cf.
Tim. 22 C
.
ζητεῖν
depends on
ἄτοπον ἡγήσεται, ἄτοπον being now taken as neuter. A reference to 525 B note will shew that Madvig's
ζητήσει (or
ζητεῖν δεῖν), and Richards'
ζητοῦντα, with other conjectures, are wholly beside the mark. J. and C. (following Stallbaum) say
ζητεῖν “depends on
νομίζοντα with the common ellipse of
δεῖν”: but
δεῖν is not commonly omitted. In
ζητεῖν—λαβεῖν there is a slight suggestion of something like the historical Socrates' distrust of astronomy (
Xen.
Mem. IV 7. 6
).
προβλήμασιν κτλ.
Some have cited in illustration “Leverrier and Adams calculating an unknown planet into existence by enormous heaps of algebra” (De Morgan, quoted by Bosanquet p. 293: cf. Lutoslawski
Plato's Logic p. 300). The example is striking but inapposite; for, according to this passage, the visible perturbations of Uranus, which occasioned the search for Neptune, would not have seemed to Plato anything very extraordinary. Unless he is greatly exaggerating here, and I do not deny that throughout this passage there is a touch of
γενναῖον πάθος, ὥσπερ ὑπὸ μανίας τινὸς καὶ πνεύματος ἐνθουσιαστικῶς ἐκπνέον καὶ οἱονεὶ φοιβάζον τοὺς λόγους (Longinus
περὶ ὕψους 8. 4), Plato's views on law in the heavens must have undergone considerable modification before he wrote the
Laws: see the striking passage 821 B ff., and
Tim. 47 A
ff.
τὰ δ’ ἐν τῷ οὐρανῷ ἐάσομεν
: ‘we will dispense with the starry heavens.’ There is a touch of fine audacity, not to say impiety, in Plato's phrase. Greater than the starry heavens is the mind of man. Nettleship (
Lect. and Rem. II pp. 271— 277) and Bosanquet (
Companion pp. 290—293) are, as it seems to me, unduly anxious throughout the whole of this episode to minimise and explain away Plato's depreciation of the senses and their objects, although by so doing they can make his theories harmonize more nearly with the views of certain modern philosophers, and possibly also with the truth. Krohn (
Pl. St. pp. 170—174) inclines to the opposite error, although, except perhaps on verbal grounds, Plato would not quarrel with his definition of Platonic astronomy as “die Wissenschaft von den Bewegungen intelligiblen Körper.” Plato's Astronomy is in fact a kind of idealised Kinematics, with occasional illustrations from the visible movements of the heavenly bodies (
τῇ περὶ τὸν οὐρανὸν ποικιλίᾳ παραδείγμασι χρηστέον κτλ. 529 D).
οἶμαι δέ γε κτλ.
526 C note
ἀλλὰ γὰρ κτλ.
Socrates means: If you criticise my curriculum (as in
ἦ πολλαπλάσιον—προστάττεις), you are doubtless ready with suggestions of your own: hence I appeal to you: ‘what suitable study can you suggest?’ ‘I cannot,’ says Glauco, ‘make
any suggestion straight off.’
ἀλλὰ γάρ (‘however’ as in
Theaet. 144 B
,
Symp. 220 E
) goes closely with the previous sentence; if it were otherwise, Plato would have added
ἦν δ’ ἐγώ or the like. The reading
ἀλλὰ γάρ τι (
q Vind. F, Hermann etc.) can hardly stand; nor is Steinhart's
ἄλλο γάρ τι κτλ., or Richards'
ἀλλὰ γὰρ <ἄλλο> τι (or
ἀλλὰ γὰρ <ἔτι> τι) pleasing or probable. I formerly suggested
ἀλλὰ γάρ τι ἔχεις <σὺ> ὑπομνῆσαι κτλ., the other subjects having all been suggested by Socrates and not Glauco, with the partial exception of geometry 526 C; but now believe (with Schneider) that the text is sound.
πλείω κτλ
. φορά is (according to both Plato and Aristotle) a specific variety of
κίνησις, being in fact,
ἡ κατὰ τόπον κίνησις. Of the genus
κίνησις Plato enumerates ten varieties in
Laws 893 B ff.; of
φορά in particular some specific
εἴδη are mentioned by Arist.
Eth. Nic. X 3 1174^{a} 30 ff.
πρὸς τούτῳ
: “praeter astronomicum
φορᾶς s. motus genus” (Stallbaum).
ὡς πρὸς ἀστρονομίαν κτλ
. ἀστρονομία is
φορὰ βάθους (528 E note), and appeals to the eye in the same way as
ἐναρμόνιος φορά, or movement in accordance with the laws of
ἁρμονία (III 397 B, 398 D, E notes), appeals to the ear. In
ἐναρμόνιος φορά the air moves more or less quickly etc., and this accounts for the different pitch etc. of notes: see
Tim. 67 B
, 80 A ff. and Theo Smyrn. p. 50 Hiller, where this—Pythagorean as well as Platonic—theory of sound is very clearly explained. Cf. also von Jan
Musici Scriptores Graeci pp. 130 ff.
ἀδελφαί τινες
. Cf. [Archytas] in Mullach
Frag. Phil. Graec. I p. 564
περί τε δὴ τᾶς τῶν ἄστρων ταχυτᾶτος καὶ ἐπιτολᾶν καὶ δυσίων παρέδωκαν ἁμῖν διάγνωσιν καὶ περὶ γαμετρίας καὶ ἀριθμῶν καὶ οὐχ ἥκιστα περὶ μωσικῆς· ταῦτα γὰρ τὰ μαθήματα δοκοῦντι εἶμεν ἀδελφά, ib. p. 565 and (with J. and C.)
Tim. 47 B
, C. The sisterhood of Music and Astronomy is best seen in the ‘harmony of the Spheres’: see X 617 B note and RP^{7}. 68 B notes
ἐκείνων πευσόμεθα κτλ.
Plato does not claim to be a specialist in musical matters: cf. III 400 A. The words
καὶ εἴ τι ἄλλο πρὸς τούτοις look like a general acknowledgment of obligation throughout this part of the
Republic to the Pythagoreans. See App. II.
ἐξῆκον κτλ.
The MS reading
ἀεί, οἷ gives a weightier and better meaning than
οἷ ἀεί, which Richards proposes. For
ἀφήκειν Eusebius (
Praep. Ev. XIV 13. 5) has
ἀνήκειν, also a rare word: Stephanus conjectured
ἐφήκειν. ἀφήκειν is better, though rarer, than either: cf. (with Schneider)
ἀφίκηται in 531 D. The reference in
ἄρτι is to 529 A ff.