I shall not today attempt further to define the kinds of material I understand to be embraced within that shorthand description ["hard-core pornography"]; 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 ["The Lovers"] is not that. [Emphasis added.]
—Justice Potter Stewart, concurring opinion in Jacobellis v. Ohio 378 U.S. 184 (1964)
