In social sciences, a cross-cutting cleavage exists when groups on one cleavage overlap among groups on another cleavage. "Cleavages" may include racial, political, religious divisions in society. Formally, members of a group j on a given cleavage x belong to groups on a second cleavage y with members of other groups k, l, m, etc. from the first cleavage x. For example, if a society contained two ethnic groups that had equal proportions of rich and poor it would be cross-cutting. While the concept may have been around since antiquity the formalizing of it originated with James Madison in The Federalist, Number 10. Robert A. Dahl built a theory of Pluralist democracy which is a direct descendant of Madison's cross-cutting cleavages. The term's antonym is reinforcing cleavages", which would