Gaetano Filangieri (born 1752, Naples, Kingdom of Naples [Italy]—died 1788, Vico Equense) was a Neapolitan jurist, philosopher, and economic theorist whose La scienza della legislazione (The Science of Legislation) is considered one of the most important works of the Enlightenment. His ideas were a precursor of modern constitutionalism, and he may have influenced Benjamin Franklin and the writing of the Constitution of the United States.
In 1774 Filangieri, a Neapolitan nobleman, published the minor work Riflessioni politiche (“Political Reflections”) to support the legal reform project of statesman Bernardo Tanucci. Six years later he began publishing his magnum opus, The Science of Legislation, but he was unable to complete the projected seven-volume series before his death from tuberculosis in 1788. Nevertheless, The Science of Legislation was embraced by influential thinkers in Europe and elsewhere. Filangieri gained a reputation as a new Montesquieu. Filangieri, however, made a point of his disagreement with Montesquieu, who had treated the legal remnants of the past and the customs that had grown in the course of European history since the fall of the Roman Empire as a legitimate and natural basis for the growth of modern law and government.
Filangieri saw the complex history of Europe as the cause of social and economic disorders. Yet, what made The Science of Legislation an important text in late 18th-century political thought was Filangieri’s insistence that the reform movements of the Enlightenment tended themselves to replicate the confusions of the European legal-political system that they had set out to eliminate. Filangieri criticized Jean-Baptiste Colbert financiers and was sympathetic to Victor Riqueti, marquis de Mirabeau, and the reform spirit of the physiocrats. Nonetheless, he accepted commerce, luxury, and inequality as foundations of modern societies. What was required first, in order to reconcile trade and the nation-state and eventually to be able to reform international politics, was a profound “scientific” reconsideration of the moral philosophical foundations of modern law and government and to bring this theory together in one frame with the actual history and current practice of the political and legal system of modern Europe. The confrontation between theory and practice, as the project of Filangieri’s science advanced, was to result in a detailed legal reform program for European nation-states and their interaction as a system.