The concept of rule-governed behavior is often used in the analysis of problem solving, conceptualization, and thinking. Rule-governed behavior has been described as behavior that is controlled by verbally constructed and transmitted discriminative stimuli. Instructions, advice, and examples are typical instances of rules that govern behavior during acquisition in problem solving situations. Nevertheless, some problems arise in identifying instructions with rules and instructionally-controlled behavior with rule-governed behavior. In this article, I argue that instructions, as instances of constructed discriminative stimuli, are (...) the outcome of abstract stimulus control in humans. Descriptions of contingencies and performance may result from effective performance under abstract stimulus control. Instructions, as stimulus conditions, do not necessarily reproduce the abstract contingencies under which they were constructed. Therefore, instructions and self-instructions do not control abstract behavior. Instructions shape up new effective behavior by prompting and restricting response variation. A conceptual analysis along these arguments suggests that the usefulness of the distinction between rule-governed and contingency-shaped behaviors is questionable. (shrink)