On the origin of energy: Metaphors and manifestations as resources for conceptualizing and measuring the invisible, imponderable

This article explores the origins of metaphorical language to describe energy by reviewing the historical development of the concept by physicists since the early 19th century. In addition to examples of historical and contemporary use of metaphors in academic writing, observable manifestations of energy are identified as the origin of energy "forms." The historicalphilosophical review and presentation of examples from contemporary physics literature contribute a disciplinary foundation to recent claims about the productiveness of physics learners' use of metaphors and indicators to describe energy.