SEVEN RULES: Seven key economic principles underlying the study of economics and the operation of the economy. These seven rules are: first -- scarcity, second -- subjectivity, third -- inequality, fourth -- competition, fifth -- imperfection, sixth -- ignorance, and seventh -- complexity. See also | first rule of scarcity | second rule of subjectivity | third rule of inequality | fourth rule of competition | fifth rule of imperfection | sixth rule of ignorance | seventh rule of complexity |