Although James Madison is best known for the views he expressed in the Federalist, as he gained greater experience in the new American political system he rejected some of these early views and increasingly emphasized four propositions: (1) the greatest threat in the American republic comes from a minority, not the majority; (2) to protect their rights from minority factions, members of the majority faction must organize their own political party; (3) the danger that majorities might threaten property rights could be overcome by enabling a majority of citizens to own property, a feasible solution in America; and (4) in a republic, majorities must be allowed to prevail. Even Madison's post-1787 constitutional views, however, were flawed in at least three serious ways: (1) as an empirical proposition, his conjecture that increased size reduces the danger of factionalism is contradicted by subsequent experience; (2) in his conception of basic rights, Madison excluded more than half the adult population: women, African Americans, and American Indians; and (3) he actively supported the provision in the Constitution that gave to slave states an increase in representatives amounting to three-fifths of the slave population.Robert A. Dahl is the Sterling Professor Emeritus of Political Science at Yale University (robert.dahl@yale.edu). A past president of the American Political Science Association, his numerous publications include A Preface to Democratic Theory; Who Governs? Democracy and Power in an American City; Democracy and Its Critics; and How Democratic is the American Constitution? The author expresses his appreciation to the Political Science Departments of the University of Indiana and Stanford University for providing opportunities to offer a lecture on the subject of this essay and to profit from the discussions that followed. Thanks also to Professors Jack Rakove, Richard Mathews, and Lyman T. Sargent for their helpful criticisms and suggestions on a draft of this paper.