The historian's one task is to tell the thing as it happened. [. . .] For history, I say again, has this and this only for its own: if a man will start upon it, he must sacrifice to no God but Truth; he must neglect all else; his sole rule and unerring guide is this—to think not of those who are listening to him now, but of the yet unborn who shall seek his converse.
τοῦ δὴ συγγραφέως ἔργον ἕν—ὡς ἐπράχθη εἰπεῖν. [. . .] ἓν γάρ, ὡς ἔφην, τοῦτο ἴδιον ἱστορίας, καὶ μόνῃ θυτέον τῇ ἀληθείᾳ, εἴ τις ἱστορίαν γράψων ἴοι, τῶν δὲ ἄλλων ἁπάντων ἀμελητέον αὐτῷ, καὶ ὅλως πῆχυς εἷς καὶ μέτρον ἀκριβές, ἀποβλέπειν μὴ εἰς τοὺς νῦν ἀκούοντας ἀλλ᾿ εἰς τοὺς μετὰ ταῦτα συνεσομένους τοῖς συγγράμμασιν.
Original text (Ancient Greek)