"And then why La Tour, who painted the same painting twice, had him hiding an Ace of Diamonds in the Louvre, and an Ace of Clubs in the Kimbell Museum. That's correct, isn't it Pierre? I'm not mistaken?"
I joined in his game. One always had to sniff out the humour in my uncle's words.
"But, Uncle Charles, it's so that the museum curators can tell which is which."
—Philippe Beaussant, "Rendezvous In Venice," pg. 64