John of Salisbury is commonly and with some good reason regarded to be the first systematic political theorist of the Latin Middle Ages, a claim grounded mainly on his authorship of the magisterial Policraticus. The Policraticus is perhaps best described as the philosophical distillation of the experiences and wisdom of one of the most learned courtier-bureaucrats of 12th-century Europe. The political writings of the most prominent classical philosophers were almost entirely unknown during John's time. John believes that the ethical stringency of friendship would be the guiding principle applied in a well-ordered court. The ascription of a theory of tyrannicide to John rests primarily on two pieces of evidence. The feature of John's political theory that some may regard as its primary weakness, its unsystematic quality in comparison with the philosophical rigor of the major Greco-Roman thinkers, perhaps proves after all to be among the greatest strengths of the Policraticus.
