From a recent decision of the 7th U.S. Circuit Court of Appeal on a copyright dispute involving characters in the Spawn comic franchise (via The Trademark Blog):
“The description of a character in prose leaves much to the imagination, even when the description is detailed — as in Dashiel Hammett’s description of Sam Spade’s physical appearance in the first paragraph of The Maltese Falcon: ‘Samuel Spade’s jaw was long and bony, his chin a jutting v under the more flexible v of his mouth. His nostrils curved back to make another, smaller, v. His yellow-grey eyes were horizontal. The v motif was picked up again by thickish brows rising outward from twin creases above a hooked nose, and his pale brown hair grew down — from high flat temples — in a point on his forehead. He looked rather pleasantly like a blond satan.’ Even after all this, one hardly knows what Sam Spade looked like. But everyone knows what Humphrey Bogart looked like. A reader of unillustrated fiction completes the work in his mind; the reader of a comic book or the viewer of a movie is passive. That is why kids lose a lot when they don’t read fiction, even when the movies and television that they watch are aesthetically superior.”