Imaginative resistance refers to cases in which one’s otherwise flexible imaginative capacity is constrained by an unwillingness or inability to imaginatively engage with a given claim. In three studies, we explored which specific imaginative demands engender resistance when imagining morally deviant worlds and whether individual differences in emotion predict the degree of this resistance. In Study 1 (N = 176), participants resisted the notion that harmful actions could be morally acceptable in the world of a narrative regardless of the author’s (...) claims about these actions but did not resist imagining that a perpetrator of harm could believe their actions to be morally acceptable. In Study 2 (N = 167) we replicated the findings of Study 1 and showed that imaginative resistance is greatest among participants who experience more negative affect in response to imagining harm and are lower in either trait anxiety or trait psychopathy. In Study 3 (N = 210) we show that this is the case even when the harms assessed include both low-severity (i.e., emotional harm) and high-severity (i.e., killing) cases. Thus, people’s moral beliefs constrain their ability to imagine hypothetical moral alternatives, although this ability systematically varies on the basis of stable individual differences in emotion. (shrink)