Proceedings of the Annual Meeting of the Cognitive Science Society

Human judgments about the physical attributes of—and causalrelationship between—two colliding objects have been stud-ied extensively over the past seventy years. Recent computa-tional evidence suggests that judgments about the mass ratioof two colliding objects, as well as their perceived causal re-lation, can be explained by a coherent framework based on aNewtonian physical model and probabilistic inference result-ing from noisy observations of object movements. However,it remains unclear how the physical and causal reasoning sys-tems interact with the motion perception system when formingthese judgments. The current study aims to examine whetherhigh-level judgments are guided by object motion representedas relative motion with reference to a moving background, oras absolute motion with reference to a stationary position inthe world. Both experimental evidence and model simulationresults support the notion that physical and causal inference inobject collisions depend on relative motion rather than abso-lute motion.