Fabro’s stay in the capital of the province of Flemish Brabant in the center of Flanders and Belgium, though brief, marks a very significant period for the consolidation of his thought.

Invited by the Superior Institute of Philosophy, he holds a course in 1954 (from November 17-26) at the “Cardinal Mercier Chair” of the University of Louvain on the topic of Participation and Causality, which will allow him to further deepen the speculative originality of Thomism. The fruit of these studies will be published in the volume, Participation et Causalité selon S. Thomas d’Aquin, Louvain (1961). Here, the breaking point with the essentialist formalism of the Scholastics is delineated, exonerating western philosophy, that is, St. Thomas, from the accusation of the “forgetfulness of being” and “preparing a project to confront modern philosophy.”

In the Preface, Prof. L. De Raeymaeker, President of the Superior Institute of Philosophy of Louvain, says, “The Rev. Fr. Fabro merits our most sincere congratulations and all our recognition for the magisterial work by which he gratifies us (Louvain, November 10, 1958).”

Fabro is the fourth chair to be invited to the University of Louvain since the establishment of the Cardinal Mercier Chair in 1951. E. Gilson, H.-I. Marrou and M.F. Sciacca had been called prior to Fabro to the prestigious University.