Realism maintains that universal moral principles cannot be applied to the actions of states in their abstract universal formulation, but that they must be filtered through the concrete circumstances of time and place. The individual may say for himself: "Fiat justitia, pereat mundus (Let justice be done, even if the world perish)," but the state has no right to say so in the name of those who are in its care. Both individual and state must judge political action by universal moral principles, such as that of liberty. Yet while the individual has a moral right to sacrifice himself in defense of such a moral principle, the state has no right to let its moral disapprobation of the infringement of liberty get in the way of successful political action, itself inspired by the moral principle of national survival.