 One way to frame debates in the Systematics Wars is as scientists wrestling over the question of what constitutes good science. Here we take the opportunity to highlight what may be an under-appreciated aspect of this debate. Namely, does good science require theory? Though many of the traditional sciences studied by philosophers of science are clearly driven by (or, at least, tightly linked to) theory, this does not always appear to be the case for other sciences. Contrast Newtonian mechanics or population genetics with, say, the study of stem cells (Fagan 2013) or developmental biology (Love 2014), where it is unclear whether there are any underlying theoretical structures.