 Kaplan and Craver challenge their own view with one of the more popular dynamical/mathematical models in all of computational neuroscience, the Haken-Kelso-Bunz (1985) model of human bimanual finger-movement coordination. They point to passages in these modelers’ publications that suggest that the modelers only intended for their dynamical systems model to be a mathematically compact description of the temporal evolution of a “purely behavioral dependent variable”. The modelers interpreted none of the model’s variables or parameters as mapping onto components or operations of any hypothetical mechanism generating the behavioral data. Nor did they intend for any of the model’s mathematical relations or dependencies among variables to map onto hypothesized causal interactions among components or activities of any mechanism. As Kaplan and Craver further point out, after publishing their dynamicist model, these modelers themselves then began to investigate how the behavioral regularities their model described might be produced by neural motor system components, activities, and organization. Their own follow-up research suggests that these modelers saw their dynamicist model as a heuristic, to help neuroscientists move toward “how-possibly”, and ultimately to a “how-actually” mechanistic explanation. 