Montesquieu

Charles-Louis de Secondat, Baron de La Brède et de Montesquieu, known simply as Montesquieu, was a French magistrate, satirist and political philosopher of the early Enlightenment. His Persian Letters mocked French society through the eyes of foreign visitors, and his masterpiece, The Spirit of the Laws, studied how laws and governments are shaped by climate, customs, religion and commerce. Its argument that liberty requires the separation of legislative, executive and judicial power became one of the founding principles of modern constitutional government, above all in the United States.

Montesquieu was born in January 1689 at the Château de La Brède, south of Bordeaux, into a family of the provincial nobility; sources give the date as the 18th or 19th. His mother died when he was seven. He was educated at the Oratorian college of Juilly near Paris, took a law degree at Bordeaux in 1708 and continued his legal studies in Paris. In 1715, the year Louis XIV died, he married Jeanne de Lartigue, a Protestant, with whom he had a son and two daughters.

In 1716 he inherited from an uncle both the title of Baron de Montesquieu and the office of président à mortier, one of the senior judges, in the Parlement of Bordeaux, a high court that also had administrative powers. For about a decade he presided over its criminal chamber. He was more interested in study than in the law, however, and was an active member of the Bordeaux Academy, presenting papers on natural science as well as on politics and religion. In the mid-1720s he sold his office and devoted himself to writing.

Montesquieu became famous almost overnight with the Persian Letters, published anonymously in Amsterdam in 1721, though his authorship was soon an open secret. The book is a novel in letters written by two Persian travellers, Usbek and Rica, who visit France in the last years of Louis XIV and the Regency and describe what they see with puzzled detachment. Through them Montesquieu ridiculed the vanity of the court, the absolutism of the king, the pope's authority and the quarrels of theologians. Interwoven with this satire is the darker story of Usbek's harem in Isfahan, the capital of Safavid Persia, which descends into revolt and bloodshed while its master is away: a portrait of despotism, built on fear, that could also be read as a warning to France. The book's success helped create the eighteenth-century fashion for using imagined outsiders to criticise European customs.

Elected to the Académie Française in 1728, Montesquieu set out on a long tour of Europe, visiting Austria, Hungary, Italy, Germany and the Netherlands. From late 1729 to the spring of 1731 he lived in England, where he attended debates in Parliament, read the political press and became a Freemason. He was deeply impressed by the English constitution as it had developed after the Glorious Revolution, which he saw as a system designed to preserve political liberty.

Back at La Brède, he published Considerations on the Causes of the Greatness of the Romans and their Decline (1734), which explained the rise and fall of Rome through general causes such as its institutions, the spirit of its people and the effects of conquest, rather than fortune or the deeds of great men. He then spent some fourteen more years, with failing eyesight, on The Spirit of the Laws.

Published in Geneva in 1748, The Spirit of the Laws is a vast and loosely organised work in thirty-one books. Its central idea is that laws are not arbitrary: they arise from the relations between a society and its circumstances, including its form of government, its climate and soil, its economy, its religion, its population and its customs. Good laws must therefore suit the people for whom they are made, and a wise legislator studies these relations rather than imposing a single ideal model. This comparative, almost sociological approach was new, and later writers saw in it the beginnings of political science and sociology.

Montesquieu divided governments into three kinds, each with its own guiding principle. A republic, in which the people or part of it rules, depends on civic virtue, a love of country and equality. A monarchy, in which one person rules by fixed laws, depends on honour and on intermediate powers such as the nobility, the church and the courts, which restrain the king. Despotism, in which one person rules by his own will, rests on fear. His theory of climate, which held that hot countries tend towards despotism and cold ones towards liberty, is the part of the book that has dated worst.

The most influential chapter describes the constitution of England. Liberty, Montesquieu argued, means security under the law, and it can survive only where power checks power. If the same person or body makes the laws, executes them and judges under them, there can be no freedom. He therefore praised a system in which these three powers were held by different hands, with a legislature divided into two houses. He also argued that commerce softens manners and encourages peace, condemned slavery with bitter irony, and attacked the use of torture and the persecution of religious minorities.

The Spirit of the Laws was an immediate success across Europe, but it was attacked by Jansenists and Jesuits as irreligious; Montesquieu replied with a Defence of the Spirit of the Laws (1750), and the Catholic Church placed the book on its Index of prohibited books in 1751. Nearly blind, he died of a fever in Paris on 10 February 1755, leaving an unfinished article on taste for the Encyclopédie of Denis Diderot and d'Alembert.

His influence was enormous. Catherine the Great borrowed heavily from him in her Instruction for a new Russian law code, and the framers of the American constitution cited him more often than almost any other modern author when they designed a system of separated powers and checks and balances. French liberals of the nineteenth century, such as Alexis de Tocqueville, saw themselves as his heirs, and his emphasis on intermediate bodies and the rule of law remains central to the liberal tradition. Alongside Voltaire, he was one of the first great figures of the French Enlightenment and helped make political institutions an object of reasoned comparison. He is also a central figure in the history of political thought in France, where his defence of the parlements and nobility as checks on royal power was taken up by opponents of absolutism in the decades before the French Revolution.