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.