I was surprised to learn that Leonardo da Vinci’s Lady with an Ermine is housed in the Czartoryski Museum in Kraków, Poland. Since the museum was only a few blocks from my hotel in Old Town, I secured a ticket. As the museum’s star attraction, the da Vinci naturally drew most visitors. Yet I found myself lingering instead before a Rembrandt landscape. Before I even noticed the artist’s name, the interplay of light and shadow had stopped me in my tracks. It was a reminder that