ABSTRACT

The rise of the new modal logic in the fourteenth century was accompanied by an increasing interest in the question of whether there were other concepts having properties similar to those of basic modal notions. Knowledge and belief were widely considered as partially analogous to necessity and possibility respectively. Medieval authors generally did not operate with the conception of logical omniscience that is included in some modern theories. They treated the logic of epistemic notions from the point of view of factual attitudes. The theory of free assent was sometimes connected with the question of making moral decisions in uncertain cases, which anticipated the later controversy over probabilism and probabiliorism. While discussing the difference between theoretical and practical knowledge, William of Ockham formulated some important principles pertaining to the theory of ethics and norms in general. Ockham’s distinction between ostensive and dictative practical knowledge is obviously similar to Immanuel Kant’s distinction between hypothetical and categorical imperatives.