The Federalist papers and constitutional ratification debates
In Federalist 10, James Madison discussed the types of factions, parties and interest groups that result from differences in wealth and property, as well as differences of opinion in religion, politics or ideology. He thought that differences in wealth and rank, at least those not based on birth, were determined by the diversity in faculties or abilities in human beings, and that government had to protect such diversity. Certainly, the two major political parties that exist today have significant differences by social class, religion, race, region and income, although there are also a huge number of factions, associations, lobbyists and interest groups outside of these parties.