The idea of a state based on the rule of law dates back to Plato, and Cicero justified the relationship between state and law, politics and law. He saw in the state the coordinated legal interaction of free members of a society, and not simply set of people living nearby, obeying uniform rules for all. The philosophical substantiation of the idea of a law-governed state is most fully presented in I. Kant's works. Only the united will of all persons forming a nation, according to Kant, can be the source of laws in a state governed by the rule of law. Having the right to participate in a common decision, everyone at the same time is obliged to obey it strictly. Equality before the law shall be an inalienable right of a citizen. It means that any citizen has the right to recognize only such power over himself, which strictly observes the same laws as he does. A state governed by the rule of law is in itself the greatest achievement of civilization.