Under every stone, my friend, beware of a scorpion.

Fragment quoted by the scholiast on Aristophanes, Thesmophoriazusae, 529, as translated by J. M. Edmonds, Lyra Graeca, Vol. 3 (1927), p. 77; Aristophanes: τὴν παροιμίαν δ᾿ ἐπαινῶ | τὴν παλαιάν· ὑπὸ λίθῳ γὰρ | παντί που χρὴ | μὴ δάκῃ ῥήτωρ ἀθρεῖν.—"I approve the old proverb; for sure it is well to look under every stone lest an orator bite you."