The Spirit of Law is a treatise on political theory, as well as a pioneering work in comparative law, published in 1748 by Charles de Secondat, Baron de Montesquieu. Originally published anonymously, partly because Montesquieu's works were subject to censorship, its influence outside France was aided by its rapid translation into other languages. In 1750 Thomas Nugent published the first English translation. In 1751 the Roman Catholic Church added De l'esprit des lois to its Index Librorum Prohibitorum. Yet Montesquieu's treatise had an enormous influence on the work of many others, most notably: Catherine the Great, who produced Nakaz ; the Founding Fathers of the United States Constitution; and Alexis de Tocqueville, who applied Montesquieu's methods to a study of American society, in Democracy in America. Macaulay offers us a hint of Montesquieu's continuing importance when he writes in his 1827 essay entitled "Machiavelli" that "Montesquieu enjoys, perhaps, a wider celebrity than any political writer of modern Europe." Montesquieu spent around twenty-one years researching and writing De l'esprit des lois, covering a huge range of topics including law, social life and the study of anthropology, and providing more than 3,000 commendations. In this treatise Montesquieu argued that political institutions needed, for their success, to reflect the social and geographical aspects of the particular community. He pleaded for a constitutional system of government with separation of powers, the preservation of legality and civil liberties, and the end of slavery.
Constitutional theory
In his classification of political systems, Montesquieu defines three main kinds: republican, monarchical, and despotic. As he defines them, Republican political systems vary depending on how broadly they extend citizenship rights—those that extend citizenship relatively broadly are termed democratic republics, while those that restrict citizenship more narrowly are termed aristocratic republics. The distinction between monarchy and despotism hinges on whether or not a fixed set of laws exists that can restrain the authority of the ruler: if so, the regime counts as a monarchy; if not, it counts as despotism.
Principles that motivate citizen behaviour according to Montesquieu
Driving each classification of political system, according to Montesquieu, must be what he calls a "principle". This principle acts as a spring or motor to motivate behavior on the part of the citizens in ways that will tend to support that regime and make it function smoothly.
For democratic republics, this spring is the love of virtue—the willingness to put the interests of the community ahead of private interests.
For monarchies, the spring is the love of honor—the desire to attain greater rank and privilege.
Finally, for despotisms, the spring is the fear of the ruler.
A political system cannot last long if its appropriate principle is lacking. Montesquieu claims, for example, that the English failed to establish a republic after the Civil War because the society lacked the requisite love of virtue.
A second major theme in The Spirit of the Laws concerns political liberty and the best means of preserving it. "Political liberty" is Montesquieu's concept of what we might call today personal security, especially in so far as this is provided for through a system of dependable and moderate laws. He distinguishes this view of liberty from two other misleading views of political liberty. The first is the view that liberty consists in collective self-government—i.e. that liberty and democracy are the same. The second is the view that liberty consists in being able to do whatever one wants without constraint. Not only are these latter two not genuine political liberty, he maintains, but they can both be hostile to it. Political liberty is not possible in a despotic political system, but it is possible, though not guaranteed, in republics and monarchies. Generally speaking, establishing political liberty on a sound footing requires two things:
The separation of the powers of government.
The appropriate framing of civil and criminal laws so as to ensure personal security.
This book concerns explicit laws, not in unwritten cultural norms that may support the same goals. "Montesquieu believed the hard architecture of political institutions might be enough to constrain overreaching power — that constitutional design was not unlike an engineering problem," as Levitsky and Ziblatt put it.
Climate, culture, and society
The third major contribution of The Spirit of the Laws was to the field of political sociology, which Montesquieu is often credited with more or less inventing. The bulk of the treatise, in fact, concerns how geography and climate interact with particular cultures to produce the spirit of a people. This spirit, in turn, inclines that people toward certain sorts of political and social institutions, and away from others. Later writers often caricatured Montesquieu's theory by suggesting that he claimed to explain legal variation simply by the distance of a community from the equator. While the analysis in The Spirit of the Laws is much more subtle than these later writers perceive, many of his specific claims lack rigour to modern readers. Nevertheless, his approach to politics from a naturalistic or scientific point of view proved very influential, directly or indirectly inspiring modern fields of political science, sociology, and anthropology.
