The Thinker is not my favorite Rodin sculpture. But then something brought me closer to The Thinker. In a glass case at the Musée Rodin, displaying preparatory studies, my attention settled on a terra-cotta fragment identified as “The Thinker’s Right Foot.” His foot! Suddenly, I had a completely different feel for The Thinker. And I found myself wondering whether Rodin, too, had felt that the success of the sculpture might depend in some crucial way on getting the feet right.