Naming, Stimulus Equivalence and Relational Frame Theory: Stronger Together than Apart.

Research on human language started to change when Murray Sidman and colleagues demonstrated that a participant was able to derive unreinforced stimulus relations after conditional discrimination training. This work provided the basis for a novel approach to research on symbolic behavior and fostered the development of three main theoretical accounts: stimulus equivalence (SE), relational frame theory (RFT), and naming theory (NT). These accounts unfolded in the last decades of the twentieth century, promoting intense debate and discussion within behavior analysis. Although experimental research emerging from these three accounts is still highly active today, the theoretical discussions have, to a large extent, faded. Considering the importance of rekindling a dialogue, this article aims to describe the differences among the three accounts, but focus on their common points. We conclude by arguing that developing a more complete behavior-analytic account of human language would be served best by considering both research and theoretical analyses of SE, RFT and NT. Finally, we provide examples of two successful research groups that adopted this approach and in doing so have advanced our understanding of language within behavior analysis.