The discussion is that all behavior is determined by structure. Changes in the structure are most easily demonstrated by functional tests. By using two kinds of tests, one can determine if an automobile engine will run: (1) he can examine atom by atom the structure of the car, and (2) he can turn on the ignition key, step on the starter, and quickly know if the anatomy of the motor allows it to run. All of us would elect to use the functional method of testing to evaluate the structure of the motor.
When I refer to structure, I am including ultramicroscopic arrangement of matter as well as the microscopic and gross aspects of structure. For the purposes of this discussion, the change of glucose to glycogen, the change in adenosine triphosphate to adenosine diphosphate, the change in hemoglobin to bilirubin are treated as changes in structure. The movement of
Stead EA. An Internist Looks at Behavior. JAMA. 1966;195(7):565-568. doi:10.1001/jama.1966.03100070109031