QUASI EX CONTRACTU TENERI: RICERCHE SULL¿ORIGINE DELLA CATEGORIA DEL QUASI CONTRATTO.

The purpose of this thesis is to make a contribution to the reflection on quasi-contracts by surveying the most problematic aspects of the subject. In particular, through the analysis of the evolutionary path made starting from the classification of the sources of obligation, it will be attempted whether the quasi-contract is already attested in the classical Roman jurisprudential thought and, at the same time, to understand what is the process that led to the development of the same. The analysis is structured in four chapters. In the first one, it is outlined a brief historical evolutionary framework of the quasi-contract that starts from the reflections made by Roman jurists, in the main historical periods, and then reaches, passing through the discipline of common law and the doctrine of the seventeenth and eighteenth centuries, the reasons that led to its non-acceptance within the current regulatory framework of the Italian Civil Code of 1942. In the second part, starting from the summa divisio obligationum contained in the Institutiones of Gaius, the first question is why a partition that is originally presented as basically complete, is not in fact so, and then what can be, following the close relationship between mutuum and solutio indebiti, the perspective from which the jurist moves in the elaboration of his partition. All of this, trying to establish whether, starting from the proper juridical foundation on which the obligationes ex variis causarum figuris are based, there is any clear dialectical purpose between what Gaius asserts in his multifunctional institutional manual and the subsequent elaboration envisaged in the Libri rerum cottidianarum sive aureorum. In the third one, after that, an attempt will be made to demonstrate both the truthfulness and completeness of what has been transmitted to us in the Res cottidianae, about the tripartition of the sources of obligations and the figures that can be traced back to it, especially in the light of what was the subsequent elaboration expressed in Justinian’s Institutions, and then, questioning the relationship between obligatio and actio in personam, to establish whether, before and during the period in which Gaius lived, the cases listed among the obligationes ex variis causarum figuris were known, and likewise to ascertain whether they were treated in the same way as obligations that did not come within the category of contracts, but could, however, be approached analogically to them. Finally, in the fourth chapter, taking its cue from Justinian’s systematization, in which the threefold division of the sources of obligations was replaced by a fourfold division in which, in addition to obligations under contract and delict, there are obligations quasi ex contractu and those quasi ex delicto, a review is made of the individual obligationes quasi ex contractu contained in the Iustiniani Institutiones, in relation to those provided for in the Res cottidianae, and concludes with an analysis of the relevant passages, devoted to quasi contractus, in the Greek Paraphrase to the Imperial Institutions of Theophilus.