The philosophes (French for philosophers) were the intellectuals of the 18th century Enlightenment. Few were primarily philosophers; rather, philosophes were public intellectuals who applied reason to the study of many areas of learning, including philosophy, history, science, politics, economics, and social issues. They had a critical eye and looked for weaknesses and failures that needed improvement. They promoted a "republic of letters" that crossed national boundaries and allowed intellectuals to freely exchange books and ideas. Most philosophes were men, but some were women. They strongly endorsed progress and tolerance, and distrusted organized religion (most were deists) and feudal institutions. Many contributed to Diderot's Encyclopédie. They faded away after the French Revolution reached a violent stage in 1793.