from the Divine Comedy

Then it replied: ‘A conscience that is clouded
By its own shame or by that of another,
Will certainly feel that your words are sharp.

But none the less, all lying set aside,
Make clear to everyone the whole vision;
And let them scratch wherever they may itch.

For if your words are objectionable
For the first taste, they will yield nourishment
Afterwards, once they have been digested.

This cry of yours will do as the wind does,
Strike hardest on the summits that are highest;
And that is no small argument of honor.'

Dante, Paradiso, XVII, 124-135.

http://www.notbored.org/censor.html