What underlies children's understanding of artifacts? Studies suggest that beginning around age 7, people reason about artifacts in terms of the inventor's purpose--termed "the design stance." Our two studies emphasize another component of artifact understanding--the cultural nature of artifacts--by demonstrating people's sensitivity to an artifact's conventional use. In past studies participants were shown a novel artifact and told that someone invented it for a certain purpose and that later another person used it for a different purpose. Here we demonstrate that if participants are told that "many" people, as opposed to just "one" person, use an artifact differently, 5-year-olds, 7-year-olds, and adults do not strictly judge the artifact in terms of its invented purpose. We conclude that people's conceptions of artifacts are more complex and dynamic than has been suggested. (Contains 3 figures and 2 footnotes.)