Why doesn't the T-Rex fossil have eyes?

—Fourth-grade student Sophia, on the Tyrannosaurus Rexfossil at the American Museum of Natural History, New York City, 2002

When my grandfather and I used to take long walks along the Post Road in Connecticut, he would ask me all sorts of questions. One day, when I was about seven or eight, he posed a particularly challenging question: “Do you know why the sun rises in the east?” He was interested to see if I knew that the Earth rotated on its axis and that the sun, indeed, stood still in the center of the solar system, as somebody named Copernicus had first proclaimed. I knew nothing of Copernicus, but I did know that the Earth rotated every 24 hours.