Da novação no direito privado – A eficácia substitutiva das obrigações.
This September, Principia published Diogo Costa Gonçalves’ monograph Da novação no Direito Privado – A eficácia substitutiva das obrigações, corresponding to scientific research carried out during 2023 and 2024.
«Portuguese private law embraces the principle of the objective and subjective free modifiability of obligations while maintaining the identity of the obligatory link. It also allows for the transfer of credits and debits. This scenario raises the question of the place of novation: does the institution still have dogmatic autonomy, or is it merely a historical remnant from a time when the modification and transfer of obligations could only be achieved through an extinctive and constitutive process?
Our research led us to define a new legal effect: substitutive efficacy, consisting of the extinction of one or more legal obligations, accompanied by the creation of a new obligation with the same causa contractus in those or other legal spheres. The new obligation may have the same content as the obligation that has been extinguished (idem debitum), or it may differ (aliquid novi).
Novation consists precisely of an aliquid novi substitution, the regime of which is distinct from idem debitum substitution phenomena. Therefore, it is not a form of obligation extinction beyond performance (as the concept has historically been understood), but rather a specific form of legal effectiveness that aligns the concept with institutions that modify contractual obligations. »
