ABSTRACT
The notion that a single country with power to in¯uence world commodity prices might improve its wellbeing by imposing positive or negative tariffs on some of its imports and exports, thus abandoning free trade, goes back to Torrens (1821, 1844) and J.S. Mill (1844); and we owe the more precise notion of a non-null optimal tariff vector to Bickerdike (1906, 1907) and Edgeworth (1908). It was recognized that the existence of such a vector is jeopardized if that country's trading partners choose to retaliate by imposing tariffs of their own or if world markets are non-competitive or otherwise distorted. Subject to those quali®cations, the existence of a non-null optimal tariff vector was accepted with remarkably little dissent.1
