“On ignore le premier Inventeur de l’Art harmonique ... par la même raison qu’on ignore le premier Inventeur de chaque Science” (d’Alembert, 1762). My paper aims to reconsider competing systems of harmony in Paris and Padua in the 18th century, focusing on the terms art and science in order to work out some characteristic differences.

The discussion around the sources until 1750 regards so‐called ‘priorities’ of pure musical nature: first, the identity of a chord and its inversions and second, the origin of the diatonic scale in the three ‘note fondamentali’ or ‘sons fondamentales’. According to actual knowledge, the Paduan ‘Scuola dei rivolti’ achieves the chronological priority by narrow margin, but certainly not Rameau’s historical role in the reception.

The scenario changes drastically with Démonstrations (1750), when Rameau tries to establish his system as a system of (natural) sciences in the Academies of Sciences in Paris and Bologna. As a matter of fact, this dispute should not be confused with the mentioned ‘priorities’. I take the single controversies 1750‐79 back to the general discussion: Which principles underlie a system of music?

In his Élements (1752, 1762), d’Alembert programmatically refuses the old “proportions & progressions” and saves those parts of Rameau and Tartini he needs for his system of music as a ‘science Physico-mathématique’: the two principles deriving from ‘corps sonore’ and ‘terzo suono’. Science is here expected in fact to reduce the sensory experiences of art to principles. This idea is already present since Rameau’s Traité (1722). But are sensory experiences strictly necessary to harmony?

Calegari’s Ampia dimostrazione (1732) will now appear archaic: I suggest a reconsideration of Seicento romano from Liberati (1666) to the origin of ‘partimento’. But when Vallotti replies in 1779 to d’Alembert, refusing both Rameau and Tartini, this is the voice of the Aristotelianism in the Renaissance!