Upon Further Reflection. Chapter 6: The Evolution of Verbal Behavior. Quote 13

“We do not say that fish means or refers to fish when it is an echoic, textual, or intraverbal response. If we tend to say so when it is a tact, it is not because there is a different kind of controlling relation between the stimulus and response, but rather because the listener responds in more useful ways to the controlling stimulus.” (p. 84).