Reasoning about physical properties of objects such as heaviness by observing others' actions toward them is important and useful for adapting to the environment. In this study, we asked whether domestic dogs (Canis familiaris) can use a human's action to infer a physical property of target objects. In Experiment 1, dogs watched an experimenter opening two differently loaded swinging doors with different corresponding degrees of effort, and then were allowed to open one of the doors. Dogs chose randomly between the two doors. In Experiment 2, we gave new dogs the same test as in Experiment 1, but only after giving them experience of opening the doors by themselves, so that they already knew that the doors could be either light or heavy. In this test the dogs reliably chose the light door. These results indicate that dogs are able to infer physical characteristics of objects from the latters' movement caused by human action, but that this inferential reasoning requires direct own experience of the objects. (C) 2017 Published by Elsevier B.V.