In the beginning of recorded ethical and legal thought, the term justice was used as equivalent to righteousness in general. Justice comprised the whole of virtue and complete conformity with the approved pattern of moral conduct.For purposes of rational analysis the classic philosophers, following Aristotle preferred to restrict the terms reference to a particular virtue distinguishing between justice and equity or between justice and charity.
According to Plato justice regulates and equilibrates the other virtues. Whether writ-small within the individual psyche or writ large in the workings of the political state, its functions are to achieve harmony and to maintain equilibrium. To do these things reason must rule within the psyche and reason's embodiment must rule within the state. Justice results from each element in society doing the appropriate task doing it well.