From Mao to Mozart: Isaac Stern in China is a celebration of communication between cultures. In the shadow of this great violinist, the most populous country in the world becomes one big music school, where he coaches his Eastern counterparts to "play from the heart" after his own expansive fashion. We don't learn much about China, or about Stern, for that matter. But we hear a lot of swell music, and we see living proof of the instant understanding that's available through art, no matter how divergent societies may seem to be in other matters. Diplomats, take note.