Less divisive than ethnic or religious inequality are the problems of rank.
These mainly occur in ethnically homogenous populations. For example, in India there are four castes (Brahmins, Kshatriyas, Vaishyas, and Shudras), and in the United Kingdom there are three classes (working class, middle class, and upper class).
Because of unfair treatment by the elites, the lower classes or castes have traditionally aligned themselves with specific worker unions and political parties that represent their interests.
Education, and the redistribution of wealth through taxation, has been found to be effective in some countries for dealing with these issues. However, wherever there are groups that benefit from unearned privileges, and exercise influence due to their elite status, there will be potential for internal instability.
Chapter 24: Societal Mastery