Credit and courtesy: educating the merchant in Renaissance Milan

The starting point of this paper is the analysis of some algebra and practical mathematics manuals written in Milan between the end of the fifteenth and mid-sixteenth centuries. Its aim is to reflect on the professional and cultural training of the merchant. The basic training (reading, writing and arithmetic) is consolidated through the technical one (practical mathematics, epistolography and documentary production), but it is thanks to other skills that the training of the Renaissance merchant/banker is completed. Moreover, it is necessary to develop a series of core skills that allow one to relate within and outside the professional sphere. To establish a successful business, a merchant needs to develop a network, to create relationships, both in the local microcosm and the European macrocosm. These skills require the internalization of some ethical, aesthetic, and behavioral models in which the public and work spheres often comes to merge with the private one. Furthermore, the local network of a merchant often becomes a political relationship. In Milan, in the Sforza age as in the Spanish one, merchants/bankers play a leading role in the civil life of the city and the state. They share with the world of the office holders and the nobility a series of ethical, aesthetic and civil values that we call courtesy (cortesia, curialitas). In the last centuries of the Middle Ages this word assumed a much wider significance than it has for us today. This is a fundamental aspect: also through their participation in civic life, the merchants manage to develop his fides and credibility necessary to operate in ever wider circles. Trust and credit are closely connected, not only semantically. In short, curialitas and creditum are foundations of the profession as much as mathematical skills and they find space in the Milanese treatises prepared by the Verini, Florentine masters active in the Milan of the sixteenth century, for their school of calligraphy and abacus. A school open to everyone, young people and adults, men and women, and therefore not exclusively for the elites, but which aimed at them as a model.