The book by Georges Duby, one of the largest French medievalists, is dedicated to the social ideas of the Middle Ages. This is primarily a history of what medieval society thought about itself. But this is also a story about how such reflections correlated with reality, how they fit into more general ideological systems, what roots they had in previous eras and how they were developed in subsequent ones. If the geographical space of the study is delineated quite strictly - the North of France, then its mental space is by no means limited to the framework of one problem and one segment of history. Table of contents: From the author Field of study APPEARANCE I. First presentation II. Gerard of Cambrai and the world III. Adalberon Lansky and the royal mission IV. SystemORIGIN I. HierarchyII. Heartfelt agreementIII. OrdersIV. Functions: pray and fightV. Trinity Doudon of Saint-QuentinAbbon of FleuryPowerful and PoorEnglish VI. Heavenly pattern CIRCUMSTANCES I. Political crisisII. Competing systems HeresyPeace of GodClunian CongregationIII. Feudal Revolution ECLIPSE I. The Time of the MonksII. Fleury HelgothAndre III. Cluny Raoul GlaberCrusade and what followed IV. New timesV. The last rise of monasticismVI. At school Teachers from LanaHugo of Saint-VictorHonorius of AugustodunskyVII. In the service of the prince Galbert of BrugesJohn of SalisburyRETURN I. The real beginning of the “Three Orders”Jean of Marmoutier and Etienne de FougereAround Henry PlantagenetII. Chivalry InitiationSuperiorityIII. Centers of resistance in Paris IV. Contradictions of feudalism MoneySocial fearV. Affirmation The Art of LoveBuvinCONCLUSION