A retrospective appreciation of Willard Day's contributions to radical behaviorism and the analysis of verbal behavior.
Treat words like behavior, not mysteries—Day’s legacy says interpretation is part of good science.
01Research in Context
What this study did
Miller (1991) looks back at the life work of Willard Day. Day was a philosopher who helped radical behaviorists talk about talking. The paper gathers his key ideas and shows how they shaped the field.
It is not an experiment. It is a story-style review that honors Day’s push to treat verbal behavior like any other natural event.
What they found
The main point is simple. Day taught us to watch words the same way we watch lever presses. He said interpretation matters as much as prediction and control.
His legacy is a reminder that science needs both tight lab data and rich, everyday sense-making.
How this fits with other research
Crosbie (1993) extends Day’s theme. It says behavior analysts should reach outside their own journals and study verbal behavior to gain real-world clout.
Morris (2022) also extends Day’s influence. It gives ready-made class lessons so new BCBAs learn the history behind the science.
Demello et al. (1992) shows the problem Day tried to fix. Citation counts prove behavior-analysis journals still talk mostly to themselves.
Why it matters
You can honor Day’s legacy by adding quick verbal-behavior probes to any session. Ask, “What is this word doing for my client right now?” Then track the function, not just the form. It keeps the science natural, open, and connected to the rest of psychology.
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02At a glance
03Original abstract
Willard Day's contributions to radical behaviorism are grouped under three headings: (a) an emphasis on the distinction between radical and methodological behaviorism; (b) an emphasis on the interpretation, rather than the prediction and control, of behavior; and (c) an emphasis on the analysis of verbal behavior as a natural, ongoing phenomenon. The paper suggests that the contributions above are listed in ascending order of significance.
The Analysis of verbal behavior, 1991 · doi:10.1007/BF03392863