Cumulative Record. Chapter 14: Why We Need Teaching Machines. Quote 19

There is another sense in which the student must learn to think. Verbal and nonverbal repertoires may prepare him to behave in effective ways, but he will inevitably face novel situations in which he cannot at first respond appropriately. He may solve such problems, not by exercising some mental ability, but by altering either the external situation or the relative probabilities of an adequate response. (p. 236)