Justice
In its broadest sense, justice is the idea that individuals should be treated fairly. According to the Stanford Encyclopedia of Philosophy, the most plausible candidate for a core definition comes from the Institutes of Justinian, a 6th-century codification of Roman law, where justice is defined as "the constant and perpetual will to render to each his due".
A society where justice has been achieved would be one in which individuals receive what they "deserve". The interpretation of what "deserve" means draws on a variety of fields and philosophical branches including ethics, rationality, law, religion, and fairness. The state may pursue justice by operating courts and enforcing their rulings.