Suddenly all the shapes that were moving in the darkness came together to make a single obscene image which dominated the whole room. And the song was over.
"Priceless!" said the Clevers. "Too stark! Too virile."
... "I—I don't think I understood it," said John....
"In other words," said the singer, "you are not yet able to distinguish between art and pornography!" and advancing toward John very deliberately, he spat in his face and turned to walk out of the room.
— C.S. Lewis, The Pilgrim's Regress
"I shall not today attempt further to define the kinds of material I understand to be embraced within that shorthand description [of "obscene material"]; and perhaps I could never succeed in intelligibly doing so. But I know it when I see it, and the motion picture involved in this case is not that."
— Supreme Court Justice Potter Stewart, concurring opinion, Jacobellis v. Ohio 378 U.S. 184 (1964), emphasis added
As the judge remarked the day that he acquitted my Aunt Hortense,
To be smut
It must be ut