Theories of the mental processes people use to perform physi- cal reasoning often differ on whether they are based on simulation or on logical reasoning. Here we test how these different processes might combine in a motion-prediction task that can be solved either by simulation or by reasoning about the topology of the scene. Participants were asked to predict which of two goals a computerized ball would reach first, but in some of these scenes the ball was ‘contained’ in the same space as one goal but was topologically separated from the other. Even in these contained scenes, participants responded faster when they received motion information that would speed up simulation but not affect topological parsing. This suggests that simulation contributes to predicting short-range motion, even when alternate strategies are available.