Philoxenos of Cythera
A most distinguished dithyrambic poet. He was invited to the court of Dionysius of Syracuse, who placed some poems in his hand to correct. Philoxenos said the only thing to do was to run a line through them and put them in the fire. For this frankness he was cast into prison, but, being released, he retired to Ephesus. The case of Voltaire and Frederick II. the Great of Prussia is an exact parallel.
Bolder than Philoxenus, Down the veil of truth I tear.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
More on Philoxenos of Cythera from Infoplease: