This essay has two aims. The first is to offer an explanation concerning the problem of form in Umberto Eco’s philosophical research, showing that he deals with it while admitting that form can be a temporary element connected to a system of relationships which may be subject to variability. Namely, his reflection is open to the issue of structure. The second aim is to identify some principles that, according to this theoretical approach, may be considered a basis for a positive philosophy of the arts whose adoption might also lead to the understanding of their most recent evolutions. Focusing above all on the work Eco carried out in the years preceding the elaboration of his semiotic theory, I will pursue the following two objectives. After introducing some aspects of Eco’s philosophical methodology, I will focus on the theme of form, considering it in meta-operative terms in light of Luigi Pareyson’s ‘theory of formativity’ and in relation to the issue of structure. In the final part of the essay, I will then show how this theoretical approach provides significant resources for a positive philosophy that can successfully address the evolution of the arts.