To tell about the pigeon laboratory at Harvard during the period I was there, I must first describe the state of the science at Columbia while I was a graduat student there. The comparison provides a better “before and after” which will help me to communicate what happened at Harvard during the years when B. F. Skinner and I worked on Schedules of reinforcement.
Key words: Harvard Pigeon Lab, Columbia University, cumulative records, Harvard graduate students, Skinner