«Talis fluxus et refluxus gratiarum commanere facit civitatem», notices Albert the Great in his comment to the locus of Aristotle’s Ethica Nicomachea devoted to the nature and the role of money in the exchange. In Albert, the very fabric of a tightly-knit society appears to be an institution that guarantees this flow of mutual reciprocation. Many a contemporary study maintains that mediaeval thinkers regarded money as a commodity, a metal valuable only according to its intrinsic value; however, a thorough textual examination reveals that they were first and foremost concerned with its institutional and social dimension as a nomothetic moment of community building.

This contribution aims at clarifying the late mediaeval conceptualisation of the nature and role of money, as it emerges from the commentaries of Albert the Great and Thomas Aquinas to Ethica V.8. The peculiarities of the language adopted to render the Aristotelian terminology by Robert Grosseteste and William of Moerbeke will be highlighted as well. The question of usury will also be briefly addressed, focusing on the rationale of this canonical prohibition within an economy organised along such theoretical lines.

Money was then seen as a measure that brought together the superabundatiam and the defectum of the two parties to the exchange with respect to the justum medium. This reference point in Albert is expressed in terms of the just remuneration, labor et expensae, plus the eventual fluctuations according to the temporary relative lack of a good. For Thomas Aquinas the meson is indigentia hominum: on the one hand, need is the necessary cause of the exchange, for it brings together two non-coincident needs; on the other, it is the measure that determines how much a thing is worth. Value is not defined according to the current interpretation of lack or need that, in a utilitarian framework, yields an individual set of preferences, but it rather answers to a communitarian evaluation of what is just and unjust in an all-encompassing political body as late mediaeval Christianity. Money is thus the guarantee of the possibility to bring together the different parts of the productive community, with the aim to preserve the Arts and to guarantee a just remuneration to all the parties involved. The perpetuation of the communitas is thus ensured via the right government of the monetary system, allowing for balance among the diverging interests of debtors and creditors, producers and rentiers, merchants and workers.

Keywords: Mediaeval monetary history; Thomas Aquinas; Albert the Great; money of account; theory of value; just price; usury.