Abstract
In this paper we examine some treatises about interpretatio iuris that encode the methodology of the Italian ‘scuola del commento’, from the end of the Middle Ages onwards. Those writings reaffirm the primacy of the mens or sensus over the verba of the law. In all these treatises, the law is considered the expression of ratio rather than of the voluntas principis: therefore, its efficacy must be addressed by means of specific and different jurisprudential work. We illustrate this methodology through a detailed analysis of the treatises by C. Rogerio, B. Cepolla, S. Federici, P. A. Gammaro.