[His commitment to democratic radicalism] has made Barber one of the leading--he is also one of the most intelligent--representatives of contemporary republican political theory. He is . . . a passionate advocate of participation, citizenship, and civic virtue. --Michael Walzer, New York Review of Books Addressing the thought of six major twentieth-century philosophers Bertrand Russell, John Rawls, Robert Nozick, Bruce Ackerman, Michael Oakeshott,...