 Kilwardby and his followers regarded Aristotle’s modal syllogistic as the correct theory of modalities, the explication of which demanded various metaphysical considerations. As exemplified by the appropriation rules, they assumed that propositions of the same form had different interpretations, depending on how they were related to other propositions in a syllogism. From the logical point of view, these rules have an ad hoc character. (For some comparisons between contemporary philosophical modal logic and thirteenth-century views, see also Uckelman 2009.)