Getting Beyond Grit
Marked by Time: How Social Change Has Transformed Crime and the Life Trajectories of Young Americans by Robert J. Sampson (Harvard University Press, 2026)
Reviewed by Elizabeth Stice
Harvard sociologist Robert J. Sampson’s new book, Marked by Time, is the product of a remarkable study, following 1,000 children born in Chicago across 25 years. Such longitudinal studies are always somewhat exceptional, but, since 1995, Sampson and his colleagues have done something more uncommon, which is track different age cohorts. The big argument, and finding, is that the years of one’s birth matter much more than we think, and often more than other factors.
Marked by Time demonstrates that older and younger cohorts have very different experiences and outcomes and not just across centuries. Even accounting for race, family poverty, self-control, and for age spikes in criminality, people born in 1980 and 1995 had very different likelihoods of arrest, violent death, success in school, etc. As Sampson outlines, much of this can be assigned to changes in the prevalence of crime, policing, and exposure to lead toxicity. The factors we often think of first are not always the most important. For example, it’s true that teenagers are more likely to commit crime than people at other ages, but high self-control teens from one cohort were as likely to be arrested as low self-control teens from another (106). Sampson never completely dismisses factors traditionally considered predictive, like family history, poverty, race, and self-control, but from the data “we can see that supposedly stable individual traits like self-control are more context-dependent than commonly believed” (110).
Though Marked by Time touches on many different topics, it will be read as especially contradicting the grit and resilience school. In recent years, many families and schools have embraced grit and resilience as being the best guarantees of good outcomes for young people. Many of you have no doubt read Grit: The Power of Passion and Perseverance by Angela Duckworth, or at least have seen the related TED Talk. For big believers in grit, character formation is the key to the future for children.
Sampson leans into the conflict between his findings and the grit school. He references what he calls the “character trap,” when we consider character permanent or fixed and attribute “life failures to an individual’s low self-control or weak moral character” (4). Much of the book is Sampson demonstrating his arguments through data analysis and the data are available to the public. While Sampson does not dismiss criminal behavior or the importance of self-control, he certainly qualifies both—context matters a great deal. The reason that so few children today seem like those depicted in Kids (1995) or A Guide to Recognizing Your Saints (2006) is not that parents suddenly understood the significance of the marshmallow test.
Sampson’s arguments may seem discouraging for parents and institutions. How can we raise children well if building grit and self-control and other good character traits is less of a guarantee of success than we thought? And what about those of us adults born under a bad star?
While Marked by Time unsettles some orthodoxies, it can also be very encouraging. Decline in exposure to lead toxicity has improved outcomes for people of varied socioeconomic backgrounds. Poverty is less of a negative indicator of future success today than it was in earlier decades. And changes in gun violence and policing before COVID created a tide that lifted all boats. In a real way, “social change has the power to alter life-course development” (176). The right policies and good societal trends benefit all children, including those who are more disadvantaged in all traditional metrics.
A clear takeaway from Marked by Time is that we cannot simply retreat to our own familial hearth and guarantee good outcomes for children. Societal trends affect children in a way that cuts across all demographics and social trends can be negative as well as positive. Yet it’s also clear that when we engage with broader society and government policy, we can foster change that reverberates far beyond an individual home or school.
Marked by Time is significant for its multiple cohort approach to sociology, but it also very relevant to the moment we are in, which is increasingly driven by AI and predictive algorithms. As Sampson points out, both left and right endorse prediction mechanisms to reduce crime. We also use character-based reasoning when deciding on sentencing. However, our prediction mechanisms are deeply flawed, because they do not account for age cohort differences. For example, prior arrest relates very differently to risk of future arrest depending on the cohort. Sampson warns about “high-stakes applications where false negatives may allow harmful crimes to occur, while false positives can trigger miscarriages of justice” (177). What happens when you are judged by a prediction mechanism based on an algorithm which is based on a study which is not adjusted for people born in different years?
We have already outsourced so much to non-human reasoning, which relies on statistical models and single-cohort studies. In 2025, school surveillance systems that were handed over to AI identified a clarinet as a gun in one incident and a bag of chips as a gun in another. Police swarmed and a student was handcuffed for his Doritos. Also disturbing is the fact that the executive behind the AI company which flagged the clarinet said the incident was not an error. It matters a great deal that the models which underly predictive mechanisms are sound and that the mechanisms are not considered above questioning. Marked by Time provides important resources for evaluating and improving these types of tools.
Marked by Time does not argue that everything comes down to the date of one’s birth, but it does prove that the date of one’s birth matters more than many other factors and is very often completely overlooked. As Sampson acknowledges, there is no silver bullet for understanding trends in crime or perfectly predicting the future of a young person at birth. Marked by Time does not solve the riddle posed by Cain or fully explain the decline in teenage drinking. Yet it demonstrates very convincingly the ways that we all come of age and exist in an interconnected web of relationships. No man is an island. And like the dancing plague among illnesses, criminal trends are not static across time, even accounting for demographic differences. We all, even as individuals, have much to gain or lose from societal changes. People interested in the future of our society would do well to pick up Marked by Time.
Elizabeth Stice is a professor of history and assistant director of the honors program at Palm Beach Atlantic University. When she can, she reads and writes about World War I and she is the author of Empire Between the Lines: Imperial Culture in British and French Trench Newspapers of the Great War (2023).
