[5,56] Ἄλλος μὲν οὖν ἄν τις ἀποχρῆν ὑπέλαβεν αὐτὸ τὸ κεφάλαιον εἰπεῖν, ὅτι συλλαβὼν τοὺς μετασχόντας τῶν ἀπορρήτων βουλευμάτων ἀπέκτεινεν, ὡς ὀλίγης τοῖς πράγμασι δηλώσεως δέον· ἐγὼ δὲ καὶ τὸν τρόπον τῆς συλλήψεως τῶν ἀνδρῶν ἱστορίας ἄξιον εἶναι νομίσας ἔκρινα μὴ παρελθεῖν, ἐνθυμούμενος ὅτι τοῖς ἀναγινώσκουσι τὰς ἱστορίας οὐχ ἱκανόν ἐστιν εἰς ὠφέλειαν τὸ τέλος αὐτὸ τῶν πραχθέντων ἀκοῦσαι, ἀπαιτεῖ δ´ ἕκαστος καὶ τὰς αἰτίας ἱστορῆσαι τῶν γινομένων καὶ τοὺς τρόπους τῶν πράξεων καὶ τὰς διανοίας τῶν πραξάντων καὶ τὰ παρὰ τοῦ δαιμονίου συγκυρήσαντα, καὶ μηδενὸς ἀνήκοος γενέσθαι τῶν πεφυκότων τοῖς πράγμασι παρακολουθεῖν· τοῖς δὲ πολιτικοῖς καὶ πάνυ ἀναγκαίαν ὑπάρχουσαν ὁρῶν τὴν τούτων μάθησιν, ἵνα παραδείγμασιν ἔχοιεν πρὸς τὰ συμβαίνοντα χρῆσθαι. ἦν δ´ ὁ τρόπος τῆς συλλήψεως τῶν συνωμοτῶν, ὃν ἐξεῦρεν ὁ ὕπατος, τοιόσδε. τῶν μετεχόντων τοῦ βουλευτικοῦ συνεδρίου τοὺς ἀκμαιοτάτους ἐπιλεξάμενος ἐκέλευσεν αὐτοῖς, ὅταν λάβωσι τὸ σύνθημα μετὰ τῶν πιστοτάτων φίλων τε καὶ συγγενῶν τοὺς ἐρυμνοὺς τῆς πόλεως καταλαβέσθαι τόπους, ἐν οἷς ἐτύγχανον ἕκαστοι τὰς οἰκήσεις ἔχοντες· τοῖς θ´ ἱππεῦσι προεῖπεν ἐν ταῖς ἐπιτηδειοτάταις τῶν περὶ τὴν ἀγορὰν οἰκιῶν περιμένειν ἔχουσι ξίφη καὶ ποιεῖν, ὅ τι ἂν αὐτοῖς κελεύῃ. ἵνα δὲ μηθὲν ἐν τῇ συλλήψει τῶν πολιτῶν νεωτερίσωσιν οἱ προσήκοντες αὐτοῖς ἢ τῶν ἄλλων τινὲς πολιτῶν μηδ´ ἐμφύλιοι διὰ τὴν ταραχὴν ταύτην γένωνται φόνοι, γράμματα πέμψας πρὸς τὸν ἐπὶ τῆς πολιορκίας τῆς Φιδηναίων τεταγμένον ὕπατον ἐκέλευσεν ἀρχομένης τῆς νυκτὸς ἄγοντα τὸ κράτιστον τῆς στρατιᾶς ἥκειν ἐπὶ τὴν πόλιν καὶ πλησίον τοῦ τείχους ἐν ὀρεινῷ τόπῳ θέσθαι τὰ ὅπλα.

[5,56] Another historian, now, might have thought it sufficient to state merely the gist of this matter, namely, that the consul apprehended those who had taken part in the conspiracy and point them to death, as if the facts needed little explanation. But I, since I regarded the manner also of their apprehension as being worthy of history, decided not to omit it, considering that the readers of histories do not derive sufficient profit from learning the bare outcome of events, but that everyone demands that the causes of events also be related, as well as the ways in which things were done, the motives of those who did them, and the instances of divine intervention, and that they be left uninformed of none of the circumstances that naturally attend those events. And for statesmen I perceive that the knowledge of these things is absolutely necessary, to the end that they may have precedents for their use in the various situations that arise. Now the manner of apprehending the conspirators devised by the consul was this: From among the senators he selected those who were in the vigour of their age and ordered that, as soon as the signal should be given, they, together with their most trusted friends and relations, should seize the strong places of the (p169) city where each of them chanced to dwell; and the knights he commanded to wait, equipped with their swords, in the most convenient houses round the Forum and to do whatever he should command. And to the end that, while he was apprehending the citizens,67 neither their relations nor any of the other citizens should create a disturbance and that there might be no civil bloodshed by reason of this commotion, he sent a letter to the consul who had been appointed to conduct the siege of Fidenae, bidding him come to the city at the beginning of night with the flower of his army and to encamp upon a height near the walls.