Charles de Secondat, Baron de Montesquieu

Life and ideas

Montesquieu was a French nobleman and a magistrate in the parlement of Bordeaux who travelled widely and wrote The Spirit of the Laws (1748) after some twenty years of work. He compared the laws of many countries and argued that they must be understood in relation to the nature and principle of each government (republic, monarchy or despotism), the size and climate of the country, and the people's religion, customs and trade. Laws are therefore not simply right or wrong in the abstract. His most famous teaching, drawn partly from his study of England, is that liberty is safest when the legislative, executive and judicial powers are held by different bodies, so that power checks power. The separation of powers is written into the United States Constitution and into many others.