This article examines the diffusion and present day status of a family of unsubstantiated learning-retention myths, some of which are referred to as "the learning pyramid". We demonstrate through an extensive search in academic journals and field-specific encyclopaedias that these myths are indeed widely publicised in academia and that they have gained a considerable level of authority. We also argue that the academic publishing of these myths is potentially harmful to both professional as well as political deliberations on educational issues, and therefore should be criticized and counteracted.