 However, a problem for structuralism (developed in Stoljar 2020) is that, while placing restrictions of this sort on the notion of a physical theory helps with Hempel’s dilemma, it also seems overly stringent. Physical theories on the face of it tell you lots of things about the physical world which are not topic-neutral, for example, about mass, energy, electrons, protons and a myriad other things. The idea that we can capture all of this using a language that employs only logical/mathematical or causal/nomic vocabulary may seem an overly ambitious one. 