No very important positive advances have been made in connection with the first three provisions [talking about (1) one’s observations, (2) the manipulative and calculational procedures involved in making them, and (3) the logical and mathematical steps which intervene between earlier and later statements] because operationism has no good definition of a definition, operational or otherwise. It has not developed a satisfactory formulation of the effective verbal behavior of the scientist. (pp. 416-417)
