- Source
- Polybius. Vols. 1-4. Büttner-Wobst, Theodor, editor. Leipzig: Teubner, 1893.
- Translation
- AI-generated (gemini-3.5-flash) — machine translation; may contain errors
- Languages
- 日本語 · English · 简体中文 · 한국어
- CTS URN
- urn:cts:greekLit:tlg0543.tlg001.humanitext-grc2:9.19.1-9.19.9
- Generated
- Humanitext Reader · reader.humanitext.ai · 2026-11-07
Highlighting how the Athenian general Nicias brought ruin upon his army by delaying retreat due to a superstitious fear of a lunar eclipse, the author emphasizes the importance of astronomical knowledge and explains the mathematical method for calculating the optimal dimensions of assault ladders relative to wall height.
καὶ μὴν Νικίας ὁ τῶν Ἀθηναίων στρατηγός, δυνάμενος σῴζειν τὸ περὶ τὰς Συρακούσας στράτευμα, καὶ λαβὼν τῆς νυκτὸς τὸν ἁρμόζοντα καιρὸν εἰς τὸ λαθεῖν τοὺς πολεμίους, ἀποχωρήσας1 εἰς ἀσφαλές, κἄπειτα τῆς σελήνης ἐκλειπούσης δεισιδαιμονήσας, ὥς τι δεινὸν προσημαινούσης, ἐπέσχε τὴν ἀναζυγήν.
And indeed, Nicias the general of the Athenians, though he was able to save the army around Syracuse, and had found the fitting time of night to escape the notice of the enemy by retreating to safety, yet when the moon was eclipsed, became superstitious, as if it portended something terrible, and delayed the departure.
καὶ παρὰ τοῦτο συνέβη κατὰ τὴν ἐπιοῦσαν αὐτοῦ νύκτα ποιησαμένου τὴν ἀναζυγήν,2 προαισθομένων τῶν πολεμίων, καὶ τὸ στρατόπεδον καὶ τοὺς ἡγεμόνας ὑποχειρίους γενέσθαι τοῖς Συρακοσίοις.
And owing to this, when he made the departure on the following night, the enemy having got wind of it beforehand, it happened that both the army and the leaders fell into the hands of the Syracusans.
καίτοι γε παρὰ τῶν ἐμπείρων ἱστορήσας μόνον περὶ τούτων δυνατὸς ἦν οὐχ οἷον3 παραλιπεῖν διὰ τὰ τοιαῦτα τοὺς ἰδίους καιρούς, ἀλλὰ καὶ συνεργοῖς χρήσασθαι διὰ τὴν τῶν ὑπεναντίων ἄγνοιαν·
And yet, by merely inquiring about these matters from those with experience, he would have been able not only not to lose his own opportunities on account of such occurrences, but even to turn them to his own advantage owing to the ignorance of his opponents;
ἡ γὰρ τῶν πέλας ἀπειρία μέγιστον ἐφόδιον γίνεται τοῖς ἐμπείροις πρὸς κατόρθωσιν.
for the ignorance of one’s neighbors becomes the greatest resource to the experienced for achieving success.
ἐκ μὲν οὖν ἀστρολογίας μέχρι τῶν προειρημένων πολυπραγμονητέον. περὶ δὲ τῆς τῶν κλιμάκων συμμετρίας τοιοῦτός τίς ἐστιν ὁ τρόπος τῆς θεωρίας.
So far, then, as concerns astronomy, one must study it up to the limit mentioned. But as for the proportion of ladders, the method of calculation is somewhat as follows.
ἐὰν μὲν γὰρ διά τινος τῶν συμπραττόντων δοθῇ τὸ τοῦ τείχους ὕψος, πρόδηλος ἡ τῶν κλιμάκων γίνεται συμμετρία· οἵων γὰρ ἂν δέκα τινῶν εἶναι συμβαίνῃ τὸ τοῦ τείχους ὕψος, τοιούτων δώδεκα4 δεήσει τὰς κλίμακας δαψιλῶν ὑπάρχειν.
For if the height of the wall is given by one of the accomplices, the proper proportion of the ladders becomes obvious; for of whatever ten units the height of the wall happens to be, of twelve such units must the ladders be in generous measure.
τὴν δʼ ἀπόβασιν5 τῆς κλίμακος πρὸς τὴν τῶν ἀναβαινόντων συμμετρίαν ἡμίσειαν εἶναι δεήσει τῆς κλίμακος, ἵνα μήτε πλεῖον ἀφιστάμεναι διὰ τὸ πλῆθος τῶν ἐπιβαινόντων εὐσύντριπτοι γίνωνται μήτε πάλιν ὀρθότεραι προσερειδόμεναι λίαν ἀκροσφαλεῖς ὦσι τοῖς προσβαίνουσιν.
And the distance of the foot of the ladder from the wall, for the balance of those ascending, must be half the length of the ladder, so that they may neither, by being placed too far away, be easily broken on account of the weight of the crowd stepping on them, nor again, being placed too upright, be extremely precarious for those climbing.
ἐὰν δὲ μὴ δυνατὸν ᾖ μετρῆσαι μηδʼ ἐγγίσαι τῷ τείχει, ληπτέον ἐξ ἀποστάσεως παντὸς ὕψους τὸ μέγεθος τῶν πρὸς ὀρθὰς ἐφεστώτων τοῖς ὑποκειμένοις ἐπιπέδοις.6
But if it is not possible to measure it or to approach the wall, one must take from a distance the size of any height of those things which stand at right angles to the underlying levels.
ὅ τε τρόπος τῆς λήψεως καὶ δυνατὸς καὶ ῥᾴδιος τοῖς βουλομένοις πολυπραγμονεῖν τὰ παρὰ τῶν μαθηματικῶν.
And the method of taking this measurement is both possible and easy for those who wish to study the principles of mathematicians.
- 9.19.1ἀποχωρήσας
The aorist participle ἀποχωρήσας is best understood as expressing means or condition ("by retreating" or "if he had retreated") modifying the potential action of δυνάμενος σῴζειν, rather than a completed historical fact, since Nicias in fact delayed and failed to execute the retreat.
- 9.19.2αὐτοῦ νύκτα ποιησαμένου τὴν ἀναζυγήν
A genitive absolute construction (αὐτοῦ... ποιησαμένου τὴν ἀναζυγήν). The pronoun αὐτοῦ serves as the subject of the participle ποιησαμένου, showing a hyperbaton where αὐτοῦ is inserted between κατὰ τὴν ἐπιοῦσαν and νύκτα. It means "when he made the departure on the following night."
- 9.19.3οὐχ οἷον
The idiomatic phrase οὐχ οἷον followed by the infinitive παραλιπεῖν functions as "not only not" or "far from [losing]," corresponding with ἀλλὰ καί to express "not only would he not have lost his own opportunities, but he would even have..."
- 9.19.6οἵων γὰρ ἂν δέκα τινῶν εἶναι συμβαίνῃ... τοιούτων δώδεκα
A correlative construction pairing the relative οἵων with the demonstrative τοιούτων, forming a general conditional relative clause with ἄν + subjunctive (συμβαίνῃ). It expresses the general ratio of 10 to 12 ("whatever ten units the height of the wall happens to be, twelve such units...").
- 9.19.7τὴν δʼ ἀπόβασιν
Although ἀπόβασις literally means "disembarkation" or "landing," in the technical context of ladder placement it refers to the horizontal distance from the base of the ladder to the wall.
- 9.19.8των προς ορθας εφεστωτων τοις υποκειμενοις επιπεδοις
A geometrical expression where the perfect active participle των εφεστωτων (from εφιστημι) in the genitive modifies υψους, accompanied by the prepositional phrase προς ορθας (at right angles). τοις υποκειμενοις επιπεδοις is in the dative, governed by the prefix επι- in the participle, meaning "things standing perpendicular to the underlying planes."