Liberal Rights in a Pareto-optimal Code

A Millian response is presented to Sen's celebrated Paretian liberal impossibility theorem. It is argued that Millian Paretian liberalism is possible, if the application of Paretian norms is restricted to the selection of an optimal code of liberal justice and rights, as well as to individual choices made in compliance with the rules of the code. Key steps in outlining the Millian response include suitably modifying Sen's social choice formulation of the idea of claim-right to personal liberty, and incorporating within social choice theory the distinction between a right and its direction of exercise. The Millian response is illustrated in the context of Sen's original example of the ‘prude’ and the ‘lewd’. If the argument is successful, coherent and appealing liberal versions of Pareto-inclusive philosophies such as utilitarianism, contractualism and neo-republicanism are feasible in principle.