Notes
1 Note that the explanatory value of entropy reduction at the functional level hinges upon the ability to manipulate directly the entropy of State Y. To the extent that the entropy of State Y can be manipulated only indirectly by manipulating elements in the environment, it makes more sense to say that State X is a function of those elements in the environment and that the entropy of State Y mediates the functional relation between the elements in the environment and State X (see Hayes & Brownstein, Citation1986, for a related discussion).
2 Note that the explanatory value of behavior–behavior relations at the functional level is limited by the fact that most if not all behaviors can be influenced only indirectly by changing the environment. Indeed, when the ability to influence a behavior is used as the criterion for the successful explanation of that behavior, a successful explanation of Behavior X in terms of Behavior Y requires the specification of those environmental variables that determine Behavior Y. This implies that functional explanations in psychology always boil down to knowledge about environment–behavior relations (Hayes & Brownstein, Citation1986).
3 Although our inferential model mainly focuses on evaluative stimulus-action effects, it can easily be (and already has been) generalized to explain other pathways via which evaluative behavior is established or changed (for one such example in the context of evaluative conditioning, see De Houwer, Citation2018).