Usura in fructu non est. Contro l'astrazione dei moderni

The paper aims to discover the ideological roots of the contemporary meaning of the interest debt. The interest debt is not a simple pecuniary obligation, such as the obligation to repay the principal sum, but on the contrary it is an obligation concerning a very special sum of money, the interest, which is typified on its ancillary cause , functionally linked to a loan of money. The modern perspective, which considers the obligation of interest as a sort of pecuniary obligation, is aimed at dissolving its causal link with the obligation to repay the principal sum. On the contrary, the concrete Roman perspective is more adequate to grasp the specific nature of the obligation of interest. This reveals the deep root and the still current importance of the dogmatic distinction that Roman jurists, concretely with respect to the abstraction of modern private law, realize between money and interest, affirming the principle of juridical civilization that interest is not a fruit (usura in fructu non est).