Second part of a study on good faith in the history of contract law. Aim of the study is a better understanding of the principle in each phase of its history, and an explanation - through the historical analysis - of some peculiar features of good faith in contemporary law. This second part deals with good faith in Roman law from its origins up to the I century AD. The following parts will be dealing with later Roman law and the civilian and common law traditions, up to the European civil codes and Anglo-American law.

It is a common belief that the iudicia bonae fidei - and ius gentium in general - were at first protected as ius honorarium, and that only with the passing of time they became part of the ius civile. In my opinion, the scholars were led to this conclusion by modern positivistic ideas, while there is no need to conjecture an unnecessary transformation not attested by the sources: ius gentium and iudicia bonae fidei were part of the ius civile from the very beginning.

In archaic Roman law, the defendant in a civil trial could not be acquitted, even in the absence of any proofs, unless he had the same or a better social standing than the plaintiff. This rule has nothing to do with an irrational basis of the archaic trial, but is perfectly consistent with the Roman vision of the socio-cosmic order as hierarchical. A person of high rank (a 'bonus') was believed to be more trustworthy (to have more 'fides') than one from the lower classes (a 'malus'), and this rule applied not only to the witnesses but also to the parties of the trial.

The idea of ius gentium, in the sources of the Republican period, is not restricted to a specific field of private or international law but is on the contrary quite general: it is an ancient idea, already formed in the II century BC and probably older, which conveys the Roman belief in the existence of rules in force among all peoples. These rules, when accepted in the law of the civitas, become immediately part of the ius civile, without any need of a statute and without any connections with the ius honorarium.

L’autore critica un orientamento diffuso in dottrina, secondo il quale l’espressione “iudicia contraria”, figurante in Cic. De off. III. 17.70, sarebbe qui utilizzata con un significato non tecnico, riferibile pure alle azioni scaturenti dalla compravendita e dalla locazione. A suo avviso, tale espressione ha, invece, un significato tecnico, riscontrabile pure in testimonianze di età assai vicina a quella dell’arpinate.El A. cuestiona una posición doctrina generalizada que defiende que la expresión “iudicia contraria”, recogida en Cic. De off. III. 17.70, sería utilizada con un significado no técnico referida a las acciones derivadas de la compraventa y del arrendamiento. A su juicio, por el contrario, tal espresión sí posee un significado técnico del que puede encontrarse testimonios en tiempos próximos a los ciceronianos.The author critices a well widespread opinion the expression “iudicia contraria” in Cic. De off. II. 17. 70 has in this case an atechnical meaning that can be ref...

KEYWORDS: metus, pactum, contrarius consensus, actus contrarius, risoluzione, violenza, pacta, giudizi di buona fede, iudicia bonae fidei, giudizi di stretto diritto, Giulio Paolo, pacta ex intervallo