Policraticus

Policraticus is a book of ethical and political philosophy written by John of Salisbury around 1159 belonging to the genre of advice literature Mirrors for princes directed towards the territorial ruler.Although addressing a wide variety of ethical questions, it is most famous for attempting to define the responsibilities of kings and their relationship to their subjects. It was the first book of political science to be produced during the Middle Ages.

Policraticus is a neologism saying meaning the statesman, Salisbury drew his arguments from several different sources, including the Bible and the Justinian Code. He argued for the divine right of kings, saying that

...the prince stands on a pinnacle which is exalted and made splendid with all the great and high privileges which he deems necessary for himself. And rightly so, because nothing is more advantageous to the people than that the needs of the prince should be fully satisfied; since it is impossible that his will should be found opposed to justice. Therefore, according to the usual definition, the prince is the public power, and a kind of likeness on earth of the divine majesty. Beyond doubt a large share of the divine power is shown to be in princes by the fact that at their nod men bow their necks and for the most part offer up their heads to the axe to be struck off, and, as by a divine impulse, the prince is feared by each of those over whom he is set as an object of fear. And this I do not think could be, except as a result of the will of God. For all power is from the Lord God, and has been with Him always, and is from everlasting.

This divine source allowed princes to wage just wars and required all subjects to submit to the prince's will. Salisbury argued that the prince had four responsibilities: Revere God, adore his subjects, exert self-discipline and instruct his ministers. Salisbury advocated strict punishments for lèse majesté, but argued that a prince should err on the side of mercy and compassion when enforcing his laws.

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