Nazi cruelties: Are they literally hard to imagine?

In four experiments, the characteristics of participants' mental imagery of World War II were investigated. In the first experiment, mental images of WWII were found to lack clarity compared to mental images of a Medieval war. In a second experiment, the association between the lack of clarity of WWII mental images, and the underestimation of Nazi cruelties was explored. In line with the expectation based on source monitoring theory, participants whose mental imagery was less clear more readily endorsed an item modelling denial of Nazi cruelties. In a third experiment, these findings were replicated. In experiment 4, participants' WWII mental images were manipulated by means of film footage. Ultimately, it is argued that viewing film footage of poor quality results in unclear mental images of WWII, and that lack of clarity of WWII imagery is associated with a tendency to Nazi cruelties.