The so-called "mirror of princes" or "statement of Knighthood" is a very old genre, which developed in both the East and West, whose purpose was to illustrate those who were to be rulers and authoritative powers to the territories under their sovereignty. Although perhaps the best known work in this genre is Machiavelli's The Prince, written in 1513, El político by Gracian, written in 1640, stands as one of the most remarkable examples of the genre in Spanish. The work presents the form of a commendation of Fernando, who is considered the greatest king of the Spanish monarchy. It describes the qualities and virtues of Fernando's policies for others to follow, including Felipe IV.