Columbia subject headings:
Social norms--History.
Harvard subject headings:
Christian ethics--History--Middle Ages, 600-1500
Competition, Unfair--History.
Contradiction--History.
Social norms--History.
Social values--History.
Princeton subject headings:
Christian ethics--History--Middle Ages, 600-1500.
Competition, Unfair--History.
Contradiction--History.
Social norms--History.
Social values--History.