Laudator Temporis Acti

Dionysius of Halicarnassus, Roman Antiquities 4.43.3 (tr. Earnest Cary):

He had spies scattered about in many places who secretly inquired into everything that was said and done, while remaining undiscovered by most persons; and by insinuating themselves into the conversation of their neighbours and sometimes by reviling the tyrant themselves they sounded every man's sentiments. Afterwards they informed the tyrant of all who were dissatisfied with the existing state of affairs; and the punishments of those who were found guilty were severe and relentless.

ἦσαν δ᾽ αὐτῷ πολλαχῇ διεσπαρμένοι κατόπται τινὲς καὶ διερευνηταὶ τῶν λεγομένων τε καὶ πραττομένων λεληθότες τοὺς πολλούς, οἳ συγκαθιέντες εἰς ὁμιλίαν τοῖς πέλας καὶ ἔστιν ὅτε κατὰ τοῦ τυράννου λέγοντες αὐτοί, πεῖραν τῆς ἑκάστου γνώμης ἐλάμβανον· ἔπειθ᾽ οὓς αἴσθοιντο τοῖς καθεστηκόσι πράγμασιν ἀχθομένους κατεμήνυον πρὸς τὸν τύραννον· αἱ δὲ τιμωρίαι κατὰ τῶν ἐλεγχθέντων ἐγίνοντο πικραὶ καὶ ἀπαραίτητοι.