 Aristotle in his De divinatione per somnum (“On Prophesy in Sleep”) rejects the common assumption of his contemporaries that gods may send dreams that inform about future events.Agreement between dream content and a later event is either (1) due to the fact that the dream reflects a bodily affection of the dreamer’s such as an incipient fever that stands in a known causal relationship to a later event such as the unfolding of a disease, or (2) because having had the dream makes the dreamer do what it suggested, or (3) mere coincidence. In De somniis (“On Dreams”) Boethius follows Aristotle in this, and in so doing deviates sharply from all known near-contemporary commentators on De divinatione, who—encouraged by Averroes, among others—left more room for supernatural intervention in dreams or, at the very least, left plenty of room for information about the future conveyed by celestial influence, a view for which they believed they could find support in Aristotle’s text (Ebbesen, forthcoming). In his treatise Boethius mocks “stupid people” who for entirely physiological reasons dream of dark persons or white angels and on waking up claim they have seen devils or that in a rapture they have seen genuine angels. He piously adds that he will not deny that by divine will a devil or an angel may appear to someone, but this looks like a subterfuge, and was taken as such by the men behind the 1277 condemnation, which features the proposition “That raptures and visions do not take place except through nature”.