probabiliorism

philosophy

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July 13, 2026

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Probabiliorism is a philosophical and ethical principle that states when faced with moral uncertainty, one must follow the more probable opinion. This theory, formulated in the 16th century, addresses situations where it's unclear if an action is permissible or sinful.1

An opinion is considered probable if it is supported by sound reasoning or recognized authorities. Probabiliorism was a predominant view in the 18th century, preceding equiprobabilism, which allows for following either of two equally probable opinions. The concept has roots in ancient Greek philosophy, with Carneades advocating for "probability" as a practical guide for decision-making.1

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probabilism
Probabiliorism, which enjoins following the more probable opinion, was predominant in the 18th century before the formulation of equiprobabilism (either of two equally probable opinions may be followed) by the moral theologian Alfonso Maria de’ Liguori, a doctor of the Roman Catholic church.
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Probabiliorism, which enjoins following the more probable opinion, was predominant in the 18th century before the formulation of equiprobabilism (either of two equally probable opinions may be followed) by the moral theologian Alfonso Maria de’ Liguori, a doctor of the Roman Catholic church.
Read More