For some thousands of years the concept of justice has been widely discussed in philosophy, jurisprudence, and theology. But there have been are no results, which are acceptable worldwide. So it seems to be time for a paradigm change: The Justice of nations - and as well the solidarity - can be represented by statistical values, arising from observation and measurement. Justice according to this new paradigm is an objective value, which characterizes nation states.

Instead of national legal norms we introduce universal norms, applicable worldwide. Each norm n(i) contributes more or less to the avoidance of human inflicted destruction of our global civilization. Elementary norms - e. g. norms prohibiting violence, theft or cheating - can be identified by common sense, non-elementary norms only by empirical research. By computer simulation m-tuples {n(i)} of norms have to be constructed, because norms of m-tupels are mutually strongly correlated.

Though norms are identified by their global effects, each norm, universally observed, contributes - as can be shown - to protect individuals from harm through human agency. Due to correlations among actions, prohibited by norms, agents have to obey all norms of an {n(i)} to ensure that no harm arises.

As common sense tells us, norms are only obeyed with a certain probability, varying from zero to one. These observable probabilities or risks form the descriptor of the social system to be investigated.

If the totality of risks (i) of {r(i)} equals zero, nations would contribute their maximum to avoid global self-destruction. Furthermore no human being worldwide would suffer from man harm by human agency. This maximal situation - which we call the basic state -is never reached in reality. The smaller the risks r(i) of {r(i)}, the better a nation's contribution to global stability and the better for individual life chances in the nation. To minimize individual harm and maximize total stability, national solidarity must be as high as possible. Only if each agent, carrying smaller or greater responsibility, plays his role, can this goal be actually reached. Hence the total harm arising in a nation is an index of the degree of its achieved actual total solidarity.

Due to correlations among the norms of the state vector it might in most cases suffice to measure regularly the so-called social temperature T: T is higher the higher the risks pertaining to norms prohibiting any kind of violence including violence of state authorities against citizens. The higher the value of T, the more unstable the nation and the more citizens suffer from human-induced harm. Therefore a higher T is an alarm signal and a lower T a sign of greater interior tranquility.

Justice only becomes a problem, if state authorities or citizens violate norms harming human beings. Then public authorities have to intervene to limit the harm arising from the contravention of norms. The intervention is successful, if additional harm including imprisoning by the intervention is small compared with the original harm. The value of the nation's total harm after all contraventions of norms in {n(i)} and all interventions measures the actual value of justice in the respective nation. This value may change from year to year as can the value of T.

If the state intervention is neither promptly nor successfully carried out, then the first violation of a norm can be compared to an infection which may spread throughout the nation and raise the overall risk of self-destruction.

This empirical approach to "The Theory of Justice" can serve to diagnose a nation`s current situation and its foreseeable evolution in the nearer future. It cannot, however, solve political problems in detail, concerning the nature of successful interventions for strengthening interior or exterior peace and as well "peace of nature".