In 1935, a senior at the fledgling St. Andrew’s School in Delaware applied to Princeton University. His grades were terrible, almost all Ds in his final term. But the headmaster rated the applicant an ”unusually good” student, describing him as “a brilliant & versatile boy who has made a special contribution to the School from the funds of his particular genius.” The student’s problem, he said, wasn’t a lack of scholarly prowess but an astonishing array of distracting extracurricular activities.

“Hollingsworth Whyte,” the...

In 1935, a senior at the fledgling St. Andrew’s School in Delaware applied to Princeton University. His grades were terrible, almost all Ds in his final term. But the headmaster rated the applicant an ”unusually good” student, describing him as “a brilliant & versatile boy who has made a special contribution to the School from the funds of his particular genius.” The student’s problem, he said, wasn’t a lack of scholarly prowess but an astonishing array of distracting extracurricular activities.

“Hollingsworth Whyte,” the headmaster concluded, “is an unusually brilliant boy whose temperament is such that he can scarcely be classified in the ordinary way.” The boy with the D-laden transcript joined the Princeton class of 1939.

Over the next six decades he would prove himself indeed brilliant, versatile and difficult to classify. In “American Urbanist,” journalist Richard Rein tells the story of William H. Whyte’s particular genius and why it exercises an enduring influence on American life. Toward the end of his life, Whyte confided the fear that “no one will ever remember what I’ve done.” Mr. Rein’s biography demonstrates that isn’t the case. “Holly Whyte’s my hero,” a half dozen sources told him.

Best known as the author of the 1956 bestseller “The Organization Man,” Whyte warned against “groupthink,” a word he coined in a 1952 Fortune article to describe “rationalized conformity—an open, articulate philosophy which holds that group values are not only expedient but right and good as well.” Like such other midcentury intellectuals as David Rieisman, Ayn Rand and Betty Friedan, Whyte defended the out-of-step individual against a social ethic that celebrated “belongingness” above all else. He was not an opponent of large organizations but a constructive critic who feared they would squelch the novel ideas on which their future depended.

William H. Whyte in New York City, ca. 1989.

Photo: Bill Foley/Getty Images

“Every great advance has come about, and always will, because someone was frustrated by the status quo; because someone exercised the skepticism, the questioning, and the kind of curiosity which, to borrow a phrase, blows the lid off everything,” he said in a layman’s sermon at Manhattan’s Episcopal Church of the Epiphany in 1953. Mr. Rein first heard of Whyte when the president of Princeton quoted that passage in his 1965 address to the freshman class.

In October 1941, two years after graduating with an English degree, Whyte enlisted in the Marine Corps. Leading a platoon on Guadalcanal and teaching combat intelligence at Quantico, Va., he developed the skills that would distinguish his life’s work: closely observing, without prejudice or immediate interpretation; recording careful notes, including maps; and making sense of a large mass of observations. Seeing what was there, not what was assumed to be there, could make the difference between life and death.

After the war, Whyte brought his reportorial skills to Fortune, a publication whose generous budgets, sociological bent, in-depth research and powerful connections nurtured a generation of public intellectuals. Journalistic empiricism suited Whyte’s temperament. He scorned “scientism,” with its “promise that with the same techniques that have worked in the physical sciences we can eventually create an exact science of man.” (The left-leaning Mr. Rein does not let on that in “The Organization Man” Whyte cited F.A. Hayek and Eric Voegelin, icons of the right, as fellow scientism critics.) Whyte preferred social studies to social science. “The study of man and society is quite worthy enough an occupation without being saddled with the task of hammering out a finite, embracing science,” he wrote.

Whyte’s years at Fortune led to three books: “Is Anybody Listening?” (on the failures of corporate communications); “The Organization Man”; and “The Exploding Metropolis,” an edited volume of essays, originally published as a series in Fortune, “by people who like cities.” That collection included a blockbuster essay by Jane Jacobs, her first with a byline. (She’d previously written unsigned features in Architectural Forum.) Titled “Downtown Is for People,” Jacobs’s piece was a detailed and devastating attack on redevelopment projects. They might look good on paper or conform to architectural theory, she argued, but they were based on false assumptions and obliterated the sources of urban vitality. To understand cities, wrote Jacobs, “You have to get out and walk.” She and Whyte were kindred souls: observant connoisseurs of the spontaneous orders of city life.

“Look at what your girl did for us!” Whyte enthused to her Architectural Forum editor. “This is one of the best responses we have ever had.” He helped Jacobs obtain funding from the Rockefeller Foundation to expand the article into her masterpiece, “The Death and Life of Great American Cities.” When she needed more time, he heartily endorsed additional support. “I believe a great and influential book is in the making,” he told the Rockefellers, who gave Jacobs a total of $18,000, more than $170,000 in today’s money.

“The Organization Man” made Whyte famous but, as Mr. Rein’s title suggests, he spent most of his career analyzing how cities work. Over the four decades between when he left Fortune and his death in 1999, Whyte thought about how to preserve open countryside and historic buildings while encouraging lively urban spaces. Under the patronage of Laurance Rockefeller, he probed the assumptions behind city plans, often arguing for the opposite conclusion. Too much open space could be as great a problem as too little. “Open space, like development, needs the discipline of function,” he wrote. Public places didn’t get overcrowded if they offered places to sit. They were underused if they didn’t. People, wrote Whyte, “determine the level of crowding, and they do it very well.”

Beginning in 1970, he and a team of interns continuously observed public spaces in New York, recording how people used them. They took notes and made time-lapse films. The goal was to collect enough close observations to discover patterns. Small design variations, Whyte found, could radically change how hospitable a public place was.

People would rarely go up or down more than about 3 feet to enter a park or plaza. Food vendors and (preferably movable) seating could turn just about any open spot into a gathering place. Seemingly shaded plazas were often illuminated by sunlight bouncing off buildings. “How could Whyte tell the difference?” Mr. Rein writes. “Over the course of eight years of filming on several streets he had to change the exposure settings on his cameras by a half-stop to adjust for increased light.”

The triumph of Whyte’s careful observation was the remaking of Manhattan’s Bryant Park, adjacent to the New York Public Library. The park had steep steps and was about 4 feet above street level, with a wall topped by a spiked iron fence ringed by thick shrubs. As crime escalated in the 1970s, this forbidding design proved disastrous. Whyte was once run out of the park at knife point. “The park will be used by people when it is opened up to them,” he said. A critical mass of law-abiding citizens would transform it. The overhaul took more than a decade, but when the park reopened in 1992, Whyte was proved right.

Mr. Rein treats Whyte as a hero, for good reasons. He was an independent thinker, an astute observer, and an admirable champion of bottom-up creativity and urban dynamism. He was wise about how cities work. But he had his own prejudices, notably against cars and the “sprawl” they enabled. Mr. Rein does not question the shortcomings of an urbanism that condemns such engines of economic and cultural creativity as Los Angeles, Atlanta and Silicon Valley. Why do these places work, if crowded sidewalks and obvious city centers are essential to urban vitality?

And then there are the Nimbys, whom Whyte’s work empowered. Facing the planner-driven destruction of neighborhoods, he and Jacobs advocated greater regulatory engagement by residents. That was an understandable reaction, but one that has had perverse results. Giving existing residents broad powers to block or delay new construction has led to housing shortages and rising rents in many cities, making them increasingly inaccessible to all but the wealthy.

Whyte looked for incentives, such as easements, to guard open land in the countryside and sunlight in high-rise corridors. In the suburbs, he envisioned “cluster zoning” that permitted dense groups of homes, possibly accompanied by commercial space, amid woodlands and meadows. But his disciples found his approach too tolerant of the building industry. “Land use regulation was the ultimate deterrent,” Mr. Rein writes. The bulldozers must be stopped.

Cluster zoning failed to take off, blocked by fearful suburbanites. Laws designed to curb development on open land, notably the California Environmental Quality Act, now thwart the increases in urban density that Whyte deemed essential. Putting too much faith in better-informed regulation, the man who eschewed general theories of human behavior ignored the political economy of land use and the power of the status quo.

Whyte didn’t intend to choke off new housing in the nation’s most productive regions or to paralyze the general ability to build. But those conditions are as much his legacy as the resurgence of old downtowns or the plentiful seating in Bryant Park—at least until someone new comes along and “blows the lid off everything.”

—Ms. Postrel is a visiting fellow at the Smith Institute for Political Economy and Philosophy at Chapman University, a columnist for Bloomberg Opinion, and the author, most recently, of “The Fabric of Civilization.”