Could an institution as sacred and traditional as marriage undergo a revolution? Some people living during the so-called Age of Enlightenment thought so. By marrying for that selfish, personal emotion of love rather than to serve religious or family interests, to serve political demands or the demands of the pocketbook, a few but growing number of people revolutionized matrimony around the end of the eighteenth century. Marriage went from being a sacred state, instituted by the Church and involving everyone to - for a few intrepid people - a secular contract, a deal struck between two...