IT IS A BIG DEAL IN developmental psychology to declare the existence of a new stage of life, and Arnett has devoted the past 10 years to making his case. Shortly after his American Psychologist article appeared in 2000, he and Jennifer Lynn Tanner, a developmental psychologist at Rutgers University, convened the first conference of what they later called the Society for the Study of Emerging Adulthood. It was held in 2003 at Harvard with an attendance of 75; there have been three more since then, and last year’s conference, in Atlanta, had more than 270 attendees. In 2004 Arnett published a book, “Emerging Adulthood: The Winding Road From the Late Teens Through the Twenties,” which is still in print and selling well. In 2006 he and Tanner published an edited volume, “Emerging Adults in America: Coming of Age in the 21st Century,” aimed at professionals and academics. Arnett’s college textbook, “Adolescence and Emerging Adulthood: A Cultural Approach,” has been in print since 2000 and is now in its fourth edition. Next year he says he hopes to publish another book, this one for the parents of 20-somethings。

　　If all Arnett’s talk about emerging adulthood sounds vaguely familiar . . . well, it should. Forty years ago, an article appeared in The American Scholar that declared “a new stage of life” for the period between adolescence and young adulthood. This was 1970, when the oldest members of the baby boom generation — the parents of today’s 20-somethings — were 24. Young people of the day “can’t seem to ‘settle down,’ ” wrote the Yale psychologist Kenneth Keniston. He called the new stage of life “youth。”

　　(文章节选自：纽约时报杂志)  (解雨)