The Moral Grammar of Magnifica Humanitas - A Discussion Paper

On May 15th 2026, on the 135th anniversary of Rerum Novarum, Pope Leo XIV promulgated (published on May 25th) the encyclical Magnifica Humanitas — “On safeguarding the human person in the time of Artificial Intelligence.” Two months earlier (March 2026), the author had circulated, through SSRN and RePEc (DOI: 10.2139/ssrn.6468803), The Moral Grammar of Economics: An Empirical and Mathematical Framework for Jesuit-Inspired Social Justice. The present paper performs a systematic dialogue between the two texts: (i) it identifies the doctrinal claims of Magnifica Humanitas that admit a direct mathematical operationalization through the constraints, wedges, and welfare functions developed in the Moral Grammar; (ii) it isolates the novel doctrinal contributions introduced by Leo XIV — the Babel/Jerusalem dichotomy, the disarmament of words and code, the new monopolies of AI, the culture of care, and the explicit move beyond GDP — and formalises each as new terms or constraints within the welfare architecture; (iii) it re-anchors these formal extensions in the panel-data evidence already presented in the Moral Grammar (172 countries, 1963–2024), in particular the solidarity-response coefficient ????=0.664 and the subsidiarity penalty ????=0.856; (iv) it proposes a composite Magnifica Humanitas Index (MHI) for monitoring societies along the integral-human-development frontier; and (v) it translates the result into a concrete five-point policy program for the AI era. The fusion shows that Magnifica Humanitas is not only a theological document but also a precise research agenda for a humanist quantitative economics — one in which Jesuit-inspired ethical constraints become binding mathematical inequalities rather than ornamental preambles. This paper does not claim that the encyclical was influenced by the Moral Grammar; it claims only that the architectural alignment between the two texts is precise enough to be operationally useful, especially for the global network of Jesuit and Catholic universities engaged in the post-AI re-foundation of social-economic thought.