Rogers Smith describes the adverse influence of modern liberalism's governing ideas on the development of American constitutional law and offers a new, more purposive theory to suit contemporary needs. He begins with a fresh analysis of the liberal goals shared by America's constitutional framers and points out the weaknesses of their political thought. Examining vital constitutional doctrines of due process, free speech, voting apportionment, and economic welfare, he demonstrates how contemporary law is often an incoherent patchwork of principles drawn from different historic versions of liberalism. Smith considers and discards the major modern theories in political philosophy that bear on constitutional law: the democratic relativism of Alexander Bickel and John Hart Ely, the higher-law views inherited from America's religious traditions, and the neo-Kantian liberalism of Ronald Dworkin and John Rawls. Returning instead to the early liberalism of John Locke, he suggests how a theory centered on the Enlightenment commitment to promoting human capacities for reflective self-direction, or "rational liberty," might better guide current constitutional debates.