  Chemero’s description of the animal and environment as coupled is ubiquitous in dynamical cognitive science. Coupling is a technical notion. The behaviors of objects are coupled when the differential equations that describe the behavior of one contains a term that refers to the behavior of the other. The equations that apply to the centrifugal governor, for instance, contain terms referring to the height of the flyballs and the size of the steam valve opening. The Lotka Volterra equations contain terms that refer to the number of predators and the number of prey. The co-occurrence of terms in the equations that describe a dynamical system shows that the behavior of the objects to which they refer are co-dependent. They are thus usefully construed as constituents of a single system—a system held together by the interactions of parts whose relationships are captured in coupled differential equations.