The Spirit of the Laws (French: De l'esprit des lois) is a 1748 political treatise by Charles Louis de Secondat, Baron de Montesquieu. Setting out to explain the principles underlying the laws of different nations, Montesquieu was innovative in the breadth of his comparative approach, and in considering natural factors such as climate. This nevertheless sometimes led him to pernicious conclusions, such as his belief that slavery, though wrong, was more tolerable in tropical regions.
Montesquieu's political recommendations were strongly influenced by his experiences in England, although it has often been insisted that he misunderstood English arrangements - generations of British schoolchildren have been taught that he missed the role of the Lord Chancellor as a member of the executive, legislature and judiciary. Nevertheless, his doctrine of the separation of powers was a decisive influence on the constitution of the United States.
Free online texts
Internet Archive: Montesquieu - The Spirit of the Laws, Rousseau - On the Origin of Inequality, On Political Economy, The Social Contract. Britannica Great Books of the Western World edition. EPUB, MOBI, PDF and TXT formats.
Liberty Fund: The Spirit of the Laws. EPUB, HTML, MOBI and PDF formats.
Wikisource: The Spirit of the Laws, translated by Thomas Nugent (1758). HTML and other formats.
Gutenberg: Esprit des Lois. EPUB, HTML, MOBI and TXT formats.
Wikisource: De L'Esprit des Lois. Multiple editions. HTML and other formats.
BBC In Our Time: Montesquieu, discussion programme with Melvyn Bragg and guests.
Library of Economics and Liberty: Comments on The Spirit of the Laws by Helvetius and Condorcet.
Librivox: The Spirit of the Laws, Vol I. Public domain audiobook in English. Books 1-13 also available in French.
Stanford Encyclopedia of Philosophy: Baron de Montesquieu, Charles-Louis de Secondat
Wikipedia: Montesquieu - The Spirit of the Laws
French Language resources