Obviously, there is a whole question of information and transaction costs surrounding the game between empirical social norms and positive legal norms. The former are more agile and immediate, better adapted to the circumstances, but at the same time they are not enough to guarantee peace when the interests at stake gain social relevance. There are cases in which the legal system takes advantage of the immediacy of the empirical norms to give dynamism to the daily traffic and at the same time reserves the last word for a case of serious controversy: it is the referral made by the positive right to the validity of uses and customs. A typical example of this is commercial law.
Although in another frame of reference, but in the same vision, we can find in David Hume an antecedent of this distinction between empirical and positive norms. The Scottish philosopher called the first “natural virtues” and the second “artificial virtues,” and it was precisely justice that was among the latter. In turn, in the 20th century, Friedrich Hayek expressly collected his political philosophy in order to enunciate his concept of “spontaneous order”, which, among other characteristics, consisted of that diffuse zone in which the norms have not yet bifurcated between empirical and positive – and for which reason it is so elusive to categorize the first volume of Law, Legislation and Freedom, entitled “Norms and order,” either within social theory or within the theory of law.
The truth is that – something that Hayek did not have the opportunity to address – in that diffuse area in which it is difficult to distinguish a social norm with empirical compliance from another with recognition by the legal system – to use H. L. A. Hart’s own concepts – a determining factor for both types of norms, in addition to the violence that its non-compliance or its subsequent retaliation may involve, is the opportunism that acts as an incentive for the acting agents -with which here we return to the Humean distinction between natural and artificial virtues: stability in possession, the peaceful transfer of it and the fulfillment of promises are three virtues that make up the idea of justice but that, for its fulfillment, require from the agents a general vision of the social consequences compliance or non-compliance, or the incentive provided by government sanctions in anticipation of non-compliance.
Opportunism on the part of private agents consists in preferring a present good to deferring that good in order to obtain a greater good in the future. For example, breaking a promise in a pressing situation constitutes a present greater good for the defaulter. However, the generalization of such default by all debtors would destroy a credit system that would, in the future, go against the interests of the entire society as a whole, including the defaulter himself. However, for the debtor, the default means an obvious immediate advantage, which can only be counteracted by the threat of a social sanction – stop being seen and treated as a “good businessman” – and, if this does not reach to modify their behavior, due to the threat of a legal sanction, such as compensation for non-compliance or, if necessary and if this non-compliance had been deliberate and obtained through a ruse, imprisonment.
It is here where the superiority of representative democracy is manifested over direct democracy, and of mixed systems, which combine long-term and even life-long terms or “while their good conduct lasts.” In these cases, the rulers exercise the “opportunism” of enforcing the law, following the adage of Herman Melville regarding “private vices, public benefits” or Machiavellian realism: greater wealth and, consequently, higher taxes come from societies in those that are characterized by a high fulfillment of promises and contracts, since it goes without saying that, abstaining from a present good to achieve a greater good in the future, generates in the long term a greater volume of wealth than enjoying a good present at the cost of giving up future good. If a government had to be revalidated daily, its incentive to stay in office would be to make short-term benefits prevail. Likewise, it is not only enough with a political system with stability in office, but also with legal and political responsibilities around the demand to make the long term prevail over the short term.
In this distinction between legal responsibilities and political responsibilities of officials, the Humean distinction between artificial virtues (the legal responsibility for the poor performance of the position) and the natural virtues (the personal desire to continue in office, through re-election or by avoiding impeachment). The legal-political system is articulated through opposite incentives: individuals have a “natural” tendency to breach promises, which is counteracted by the incentive of the legal system that establishes forced fulfillment of contracts; while the political system is expected to align incentives in such a way that rulers have “the natural tendency” to enforce contracts. This natural tendency of the rulers does not come from any “natural” characteristic of the person of the ruler but from the incentives provided by the constitutional system.