_I was privileged to have been associated in one form or another with the Harvard Pigeon Lab from September 1964, when I arrived as a graduate student, until my friend and colleague Gene Heyman moved out of William James Hall on June 30, 1998. After completing my graduate degree in 1968, I continued to live in Cambridge and was therefore able to continue my affiliation with the Pigeon Lab, frequenting the lab meetings to learn about the latest research and occasionally to present some ideas of my own. During the academic year 1981–1982, I was a full-time visiting scholar at the lab, regularly attending lab meetings as well as weekly conversations with Fred Skinner. These latter meetings, or "pow-wows" as Fred called them, were attended by a small group consisting of Will and Maggie Vaughan, Pere Julia, another visiting scholar at the time, and me, as well as occasional invited guest speakers (Skinner, 1983, p. 394).