Abstract

In his Mechanics of 1883, Ernst Mach opened a specific revision of the classical physics which launched a radical epistemological change in physics. Within this move, Mach introduced operational definition of physical concepts and thus changed the status of measurement in the foundation of physics. The paradigmatic change was introduced in the definition of inertial mass. This paper points to another physical concept, which went through a kind of similar change in definition – the concept of weight. In this perspective, we reviewed the history of conceptual transformation of the weight concept. We speculated for the reason that prevented this change to be performed within the classical physics as required another epistemological change introduced by Einstein in establishing of modern physics. It is within the new physics that Machian introduction of the operational concept definitions could fully develop towards operationalism and logical positivism. The anthropocentric nature of the weight concept left it however behind the frontier of theoretical physics. Yet, for the same nature, this concept remained central in physics education. The paper reviewed the status of the weight concept which divides the world of teaching physics into two big camps of educators those keeping with Newtonian definition and those who argue for the modern definition drawing on the operation of weighing. The paper suggests a new educational approach to teaching weight – disciplinary cultural one. The latter implies exposure of the conceptual dialogue regarding weight definition and making explicit the epistemological reasons for the conceptual change regarding weight being illustrated with a set of representative physical situations. The evidence of the educational priority of the new approach is mentioned.