The French political philosopher and historian François Guizot (1787-1874) was one of the French Doctrinaires, thinkers who sought to avoid the interpretations of the Revolution advanced by either extreme of Left or Right. He argued that in order to understand the nature of political institutions it is necessary to study first the society, its composition, and the relation between various classes. At the very centre of his theory lies the principle of the sovereignty of reason. The first part of the book covers the period from the fifth to the eleventh century and such topics as the "true" principles of representative government and the origin and consequences of the sovereignty of the people. The second part spans the Norman Conquest to the reign of the Tudors in England and analyzes the architecture of the English Constitutional monarchy.