[…] Arthur was saying, “I’m afraid there’s no help for it: they must be finite in number.” “I should be sorry to have to believe it,” said Lady Muriel. “Yet, when one comes to think of it, there are no new melodies, now-a-days. What people talk of as “the last new song” always recalls to me some tune I’ve known as a child!” “The day must come—if the world lasts long enough –” said Arthur, “when every possible tune will have been composed and every possible pun perpetrated –” (Lady Muriel wrung her hands, like a tragedy-queen) “and worse than that, every possible book written! For the number of words is finite.” “It’ll make very little difference to the authors,” I suggested. “Instead of saying ’what book shall I write?’ an author will ask himself ’which book shall I write?’ A mere verbal distinction!” Lady Muriel gave me an approving smile. “But lunatics would always write new books, surely?” she went on. They couldn’t write the same books over again!” “True,” said Arthur. “But their books would come to an end, also. The number of lunatic books is as finite as the number of lunatics.”
“Sylvie and Bruno Concluded” in Carroll: Complete Illustrated Lewis Carroll , p. 536