In "David and Goliath," Malcolm Gladwell, the clever and counterintuitive author of "The Tipping Point," "Blink" and "Outliers," argues that the powerful are not as powerful as they seem and that being an underdog can open doors, create opportunities and make possible what had been deemed unthinkable. Gladwell is a gifted storyteller and his accounts of basketball strategy, cancer research, dyslexia, choosing the right college, affirmative action in law schools, losing a parent, the impact of "remote misses" in the bombing of London, and resisting the Nazis are informative and often compelling. In "David and Goliath," however, his zeal to trumpet the "advantages" of physical disabilities, suffering, discrimination and adversity leads to exaggerated and unjustifiable claims.

Gladwell reminds us that underdogs have won wars against "superpowers" (in Vietnam and Afghanistan, for example) by adopting guerrilla tactics, including terrorism. And that the lawyer David Boies and Goldman Sachs president Gary Cohn have compensated for their dyslexia by learning to listen, focus, reduce arguments to their essences, and take risks.

Fair enough. But at times, Gladwell hypes the virtues of "desirable difficulties," the forces arrayed against marginal and damaged individuals, and their capacity to create the conditions that will lead to success. After all, as he acknowledges, many people with dyslexia do not overcome their disability; a "remarkable number" of them end up in prison. Gladwell's claim that before the Civil War black "tricksters" thwarted their masters because they had nothing to lose isn't true. Slaves knew, of course, that they could be tortured, separated from their families, or killed. So, too, despite the experience of the citizens of the remote village of Le Chambon, France, did anyone contemplating helping Jews in European countries occupied by the Nazis. Also questionable is Gladwell's suggestion that the existence of eminent orphans (between 1800 and 1939, 67 percent of British prime ministers lost a parent before age 16) demonstrates that society needs people "who have emerged from some kind of trauma" hardened by their experiences, because they are more willing to speak truth to power. One would hope that society can find healthier ways to foster the courage to think the unthinkable.

Gladwell concludes that "so much of what is beautiful and valuable in the world" comes not from the giant but from the shepherd, "who has more strength and purpose than we ever imagine." And that one time out of 10, "an indomitable force" rises out of adversity. It is worth noting as well, is it not, that since these odds are not at all favorable, we probably should be skeptical of characterizations of physical, emotional or material difficulties as "desirable," lest it lead to blaming the victims.

Glenn C. Altschuler is the Thomas and Dorothy Litwin Professor of American Studies at Cornell University.