At the beginning of the 20th century Einstein startled the world by suggesting that time was the fourth dimension. A century later the social sciences are still only beginning to appreciate the importance of this dimension. Adult development continues to surprise us. Psychiatry keeps having to rediscover that traumatic events occurring at one point in time do not necessarily change the individual forever. Over decades, the effects of the bad mother, the high-crime neighborhood, and the abusive father may disappear through later, more positive developmental forces.

In this groundbreaking 60-year study of the lives of juvenile delinquents, Laub and Sampson have moved the whole field of adult development forward. By focusing on the 500 seemingly doomed young reform school graduates of Sheldon and Eleanor Glueck’s classic book, Unraveling Juvenile Delinquency(1), they demonstrate that different factors are associated with climbing out of holes than failing into them.

The authors note the unique historical moment in which their protagonists found themselves. True, the paths of the Gluecks’ adolescents into delinquency had been amplified by the disorganizing social effects of the Great Depression. True, their paths away from delinquency were facilitated by the G.I. Bill, the strong economy of the 1950s, and the evolution of Irish and Italians from despised minority status into the white rulers of Boston. But the effects of social forces do not explain individual differences. Some adolescents persisted in a life of crime and some did not—why? The childhood crowding, broken families, inconsistent and harsh discipline, low IQs, and difficult temperaments that were associated with becoming chronically delinquent by age 15 were not associated with persistence in crime. The absence of such negative childhood factors was not associated with recovery. Why?

Through their ingenious graphing of criminal behavior over time, Laub and Sampson put the theory of dichotomous criminal careers to rest. There are not two kinds of criminals: one merely badly behaved adolescents who mature out of crime in their 20s and the other inveterate criminals who begin offending in grammar school and malignantly continue in crime until old age. Instead, the offending careers of both groups formed neat, overlapping bell curves. Statistically, early offenders are more likely to persist longer in crime, but after age 50, desistence is the rule, not the exception, for both groups. Thus, chronological age is one factor in desistence, but only one variable among many.

Although Laub and Sampson test their conclusions with cutting-edge statistical techniques, they demonstrate that individual life history narratives are particularly valuable in uncovering the causes of desistence. Thus, the stories and quotes in the book are both fascinating and informative. The explanation for desistence comes not from the premorbid variables that led to crime but from the encounters in adult life of supportive employment—often the military—and supportive marriages. Laub and Sampson point out that these informal social controls and interpersonal bonds that linked the once-alienated youth back to the community are what make the difference—and these turning points could occur in youth at the highest initial risk for delinquency. Both the narrative and the multivariate data analysis support "the investment-quality of good marriages." Such an investment takes time to appear, grows slowly, but inhibits crime, usually forever.

The authors’ case histories vividly identify an important—but still unanswered—question. What are the variables that determine the capacity of adults to absorb or reject fresh healing environments? For some delinquents the stability and the relative predictability of reform school, the Army, and a "ball and chain" were highly appreciated, but for other men these potentially healing experiences were just one more form of abuse.

Shared Beginnings, Divergent Lives is a profound, complex, and sometimes difficult book. Nevertheless, it is enormously rewarding. The book, destined to become a classic, will sharpen readers’ awareness of adult development forever. The lessons of this book can be applied not only to criminality but also to the natural history of drug abuse, chronic unemployment, marital turmoil, and personality disorders.