Probability and moral uncertainty in late medieval and early modern times

Abstract

Scholastic conceptions of probability prefigured modern concepts more substantially than standard historical accounts suggest. Rather than denoting solely extrinsic authority or subjective opinion, medieval probability frequently incorporated empirical assessments of frequency, objective risk, and physical regularity across legal, economic, and natural philosophical domains. The subsequent early modern debates over moral decision-making under uncertainty were fundamentally shaped by a shift from intellectualist theories of action to voluntarist psychology. Whereas classical models subordinated choice to rational deliberation, voluntarist perspectives established the primacy of the will over intellectual assent, rendering conscience an individualized, contingent process. This psychological reorientation facilitated the emergence of probabilism, which permitted agents to follow less probable opinions favoring personal liberty over legal obligation through the application of formal reflex principles. Conversely, later probabiliorist counter-arguments repudiated these reflex mechanisms, maintaining that speculative uncertainty does not excuse non-compliance with moral law and requiring subjective, prudent assent to the most probable position. The evolution of moral systems from late medieval tutiorism to early modern probabilism and probabiliorism thus reflects a continuous theoretical negotiation between the freedom of the will, empirical likelihood, and the binding authority of moral law. – AI-generated abstract.