New Haven, Connecticut, at the tail end of the 1970s was a pretty good place for a precocious kid to get a political education. The city contains all the ethnic and social dynamics of New York City or Philadelphia in microcosm. But it's small enough that a 15-year-old with a ten-speed could get to any neighborhood to knock on strangers' doors before an election or a primary, of which there were dozens. The city loved politics and was then embroiled in a fierce battle between "the reformers" and "the machine."

To make it a real education, there was a library shelf full of books about New Haven and its politics, with titles like Model City and The Mayor's Game. First among them was a long-established classic of political science that still describes the city well: Who Governs? by Yale's Robert A. Dahl, based on a close study of the city in the late 1950s.

Dahl used New Haven to answer a question he traced back to Aristotle: "In a political system where nearly every adult may vote, but where wealth, knowledge ... and other resources are unequally distributed, who really governs?" Was it a permanent overclass of the economically powerful? Was it the long-serving mayor and his sturdy coalition? Was it political party leaders, who ruled for life? Was it bureaucratic masters like the city's omnipotent director of redevelopment? As political dominance changed hands from the city's old patrician elite to Irish Americans and then Italian Americans -- groups Dahl called "the ex-plebes" -- was it the ethnic group that was dominant at that moment?

By considering each of these possibilities in turn, Dahl produced a vivid, complete portrait of a still--prosperous small city, challenged by the fading of its main industries but charged up with the fresh liberal promises of urban renewal. (New Haven's self-identification as a "model city" attracted lots of federal and foundation money, and even today it's like an old laboratory of early liberal experiments in education, housing, development, and social policy.) Unlike much academic political science, the book not only is about real politics but admits a shameless love of politics. And, true to the spirit of New Haven, politics is everywhere, in schools, neighborhoods, social clubs, and jobs.

Dahl's answer to the question in the title was an upbeat one: Power was distributed unequally, but fortunately it was a system of "dispersed inequalities" rather than "cumulative" ones. Some groups or individuals had more economic power, some more political power, some more social prestige, but those inequalities were always shifting and didn't reinforce one another. This "pluralism," he wrote, "was a long way from achieving the goal of political equality advocated by the philosophers of democracy," but it was also far preferable to the "patrician oligarchy" of New Haven in the 19th century.

To a kid imbued with the idealism of "reform," Dahl's was a bracingly sanguine view of machine politics.

It was also a controversial one. Pluralism became the dominant faith in political science for some time, an eternal optimism characteristic of the early-1960s liberal consensus. But its limits were revealed in the sharper social conflicts of the late 1960s, and in our own time, when economic and political inequality are surely "cumulative." Dahl himself took a darker view in his later work.

Rereading Who Governs? three decades on, the most striking limit of his pluralism has to do with race. Dahl expected to see African Americans moving along roughly the same path to power as the "ex-plebes" before them, the Irish Americans and Italian Americans. While African Americans never had the economic opportunities of the earlier groups, Dahl thought that politics created alternative opportunities -- government jobs instead of factory jobs. But it was clear even in 1978 that racial inequalities are indeed cumulative. Like Chicago and New York, the city has elected only one black mayor, and the growing Hispanic population has already moved more quickly to full political power.

Despite those limits, rereading Who Governs? reminds me that I drank deep of the cup of pluralism at an early age, and it shaped my view of politics as surely as those afternoons on unfamiliar doorsteps. Like so much of early 1960s liberalism, Dahl has an idea worth salvaging -- -perhaps more as an objective than as a description of reality. Instead of reaching for a reformer's ideal of political equality and democratic fairness, try at least to achieve a world in which the inequalities of money, knowledge, and status aren't always reinforced in politics, and where hierarchies of power are at least fluid. Not only is such a world the best we can achieve, but the ever-shifting struggle over the power to govern is what makes a kid -- or a city -- love politics.