Beijing boasts a modern light-rail train, the latest in electronic gadgets and luxurious hotels and restaurants. And yet some aspects of the city seem straight out of the 1800s. While driving with a friend to a section of town with high-end housing, we passed a shepherd and a flock of sheep. Late-model cars share the road with people pedaling carts. At one point I watched a mule or donkey slowly pull a cart across a wide street.

At prestigious Peking University, buying a long-distance calling card on a chilly January day meant standing in an unheated room. Similarly, the restroom of a campus restaurant was in an unheated foyer. And that made visiting it an unpleasant prospect on a day when the temperature was below freezing.

It will be interesting to see the extent to which these contrasts persist as Beijing, and China as a whole, continues to boom. Will the entire society push forward into the 21st century? Will part of it remain frozen—literally—in the past?