ἡ ψύλλα, -ης – a flea
Related to the flea (ψύλλα) is one of history’s greatest slanders: Aristophanes making fun of Socrates as an „ivory tower“ philosopher who is detached from any problems of real importance. Here are his immortal words (Aristophanes, Clouds 143-153; transl.: Jeffrey Henderson):
ἀνήρετ᾿ ἄρτι Χαιρεφῶντα Σωκράτης ψύλλαν ὁπόσους ἅλλοιτο τοὺς αὑτῆς πόδας. δακοῦσα γὰρ τοῦ Χαιρεφῶντος τὴν ὀφρῦν ἐπὶ τὴν κεφαλὴν τὴν Σωκράτους ἀφήλατο.
Just now Socrates asked Chaerephon how many of its own feet a flea can jump, because one had bitten Chaerephon’s eyebrow and jumped off onto Socrates’ head.
πῶς δῆτα διεμέτρησε;
And how did he measure it off?
δεξιώτατα. κηρὸν διατήξας, εἶτα τὴν ψύλλαν λαβὼν ἐνέβαψεν εἰς τὸν κηρὸν αὐτῆς τὼ πόδε, κᾆτα ψυχείσῃ περιέφυσαν Περσικαί. ταύτας ὑπολύσας ἀνεμέτρει τὸ χωρίον.
Very cleverly. He melted some wax, then picked up the flea and dipped both its feet in the wax, and then when the wax cooled the flea had Persian slippers stuck to it. He took these off and went about measuring the distance.
ὦ Ζεῦ βασιλεῦ, τῆς λεπτότητος τῶν φρενῶν.
Lord Zeus, what subtlety of mind!