According to Wikipedia: "François VI, duc de La Rochefoucauld, prince de Marcillac (September 15, 1613 March 17, 1680), was a noted French author of maxims and memoirs, as well as an example of the accomplished 17th-century nobleman. He was born in Paris in the Rue des Petits Champs, at a time when the royal court oscillated between aiding the nobility and threatening it. Until 1650, he bore the title of prince de Marcillac."
According to Wikipedia: "François VI, duc de La Rochefoucauld, prince de Marcillac (September 15, 1613 March 17, 1680), was a noted French author of maxims and memoirs, as well as an example of the accomplished 17th-century nobleman. He was born in Paris in the Rue des Petits Champs, at a time when the royal court oscillated between aiding the nobility and threatening it. Until 1650, he bore the title of prince de Marcillac."