In recent decades early modern probabilism, long relegated to the annals of Catholic moral theology, has made a comeback among philosophers and historians. The resulting scholarship has gone far toward erasing ingrained caricatures of probabilism—as Catholic sophistry, a theological cover for laxism, or a pawn in Jansenist-Jesuit disputes—and taking it seriously as an intellectual enterprise. Stefania Tutino's new book is a landmark in this trend. The author presents probabilism as a sustained effort to answer a fundamental human question: How do we make sound decisions in ambiguous situations, when accepted or prescribed norms do not dictate a clear course of action? How, in other words, do we resolve moral uncertainty? Probabilist theologians, she argues, confronted this question in a world of expanding horizons—geographic, cultural, and intellectual. Embracing uncertainty as a productive challenge, they developed a sophisticated epistemological toolkit to analyze complex problems and facilitate their solution. Its core principle was that an opinion deemed probable—based on “solid arguments and … the authority of learned scholars” (42)—could be chosen as the legitimate basis for action, even if a more probable alternative was available. This position differed from stricter doctrines, such as probabiliorism, which required that the most probable opinion prevail, and tutiorism, which prescribed the path entailing the least risk of sin. Thus, probabilism promised greater freedom.
On these premises probabilism gradually moved center stage in Catholic moral theology, albeit amid growing controversy. The sixteenth-century revival of confession prompted Martín de Azpilcueta to seek a legally and theologically valid, but not excessive, standard for deciding ethical issues. Bartolomé de Medina gave epistemological analysis a distinct role in outlining the range of justifiable actions. On this basis subsequent generations constructed ever more intricate theories. Jesuits played key parts in this endeavor, but also illustrated a fundamental dilemma. Francisco Suárez sought “a comprehensive taxonomy of … doubts and opinions” (76) but ended up magnifying rather than resolving uncertainty. Gabriel Vázquez, fearing rampant proliferation of opinions, insisted on their “extrinsic” validation by authorities. This tension resurfaced repeatedly over the seventeenth century. While probabilism allowed theologians to update the church's response to social issues—e.g., in marital law (Sánchez) and usury (Lessius)—it also summoned countervailing forces. Juan Azor sought to reestablish “stability” in Jesuit curricula based on Vázquez's extrinsecism, while Emmanuel Sa's pastoral Aphorismi provoked a backlash against broader dissemination of probabilist speculation. The conflict came to a head when two midcentury protagonists, Antonino Diana and Juan Caramuel, embraced innovation, fresh scholarship, and the strength of arguments rather than the authorities endorsing them. Faced with new knowledge—for example, of non-European cultures—they recognized cultural difference and the multiplicity of truth. For Diana the only checks on pluralism were Christ's dictates and papal decrees. Caramuel went further: based on radical doubt—“I knew for certain that everything is uncertain” (175)—he challenged even papal authority.
At this point, with Jansenist-Jesuit hostilities in full swing, it is not surprising to see the Roman curia intervene. Caramuel and fellow Jesuits Honoré Fabri and Alberto de Albertis endured multiple rounds of censorship, by the Jesuits, the Holy Office, and the Index. Their experiences highlight the role of polemics—theological, institutional, and/or political—in shaping these authors’ works, their reception, and their revision. Yet, while censorship required revisions of specific verdicts, it did not impugn probabilist methodology, which enjoyed broad if sometimes reluctant support in the hierarchy. Space constraints do not permit further discussion of Tutino's rich analysis of these cases, based on extensive documentation of the Roman archives of the Society of Jesus and the Congregation for the Doctrine of the Faith. The same applies to the book's final chapters, which explore probabilism's role in sorting out specific moral questions on different frontiers. How to handle differences in sexual custom among East-Asian Catholics? How to apply usury law to Jewish converts? How to answer questions about baptism elicited by embryological discoveries? To the author, the ensuing debates confirm the relevance of probabilism for the daily lives of Catholics.
This lucid, cogent, and fine-grained study succeeds brilliantly in historicizing the human problem of how to deal with cognitive and moral uncertainty—with important implications, Tutino suggests, for our current predicament. Her intellectual history portrays a Catholic elite using probabilism to find its way—and direct the faithful—in a rapidly changing world, torn by the impulses of freedom and constraint. Thus, the author nuances the emphasis recent historians have placed on the disciplinary and legal constraints enacted by the post-Reformation church. Even so, she recognizes, the hierarchy's relative openness to philosophical speculation (or their inability to reach consensus on it) was offset by their insistence to control its dissemination and application. The social consequences of probabilism, therefore, remain a subject open for further research.
