The other day I had coffee with a friend, an artist and writer, who had recently sent his daughter to college. Not long ago, she called him to share the good news that the school cafeteria has soy yogurt—a type of joyous, off-the-cuff communication that was so unlike the defiant, secretive adolescent he and his wife had been living with. The college girl is launched; her father bereft.

"I was involved with her every day for all of these years, and she was so interesting to me," he said. "Now what am I supposed to do with my life?"