To Montesquieu belongs the honor of pioneering the movement out of which grew the philosophical dictionaries, encyclopedias, and the literary crusade against mental subjection. If ever satire had a distinct call to duty it was during the Regency in France. Montesquieu adopted the device of a series of familiar letters exchanged by two Persian travelers in France. They were completed in 1721. Popular taste was captivated by the wit and pleasantry of the Letters. They gently satirized the abuses rife in church and state; society was held up to ridicule for its pet sins.