B. F. Skinner titled this book, Contingencies of Reinforcement, after the heart of his science of behavior. Contingencies relate classes of actions to postcedent events and to the contexts in which those action-postcedent relations occur. The basic processes seem straightforward, but many people do not know or understand the underlying theory. Skinner believed that ‘a theory is essential to the scientific understanding of behavior as a subject matter”. This book presents some of Skinner’s most sophisticated statements about theoretical issues. To his original articles, he added notes to clarify and expand subtle points. The book thus provides an overview of Skinner’s thinking about theory and the philosophy underpinning the science he began.

The contingent relationship between actions and their consequences lies at the heart of Skinner’s experimental analysis of behavior. Particular patterns of behavior emerge depending upon the contingencies established. Ferster and Skinner examined the effects of different schedules of reinforcement on behavior. An extraordinary work, Schedules of Reinforcement represents over 70,000 hours of research primarily with pigeons, though the principles have now been experimentally verified with many species including human beings. At first glance, the book appears to be an atlas of schedules. And so it is, the most exhaustive in existence. But it is also a reminder of the power of describing and explaining behavior through an analysis of measurable and manipulative behavior-environment relations without appealing to physiological mechanisms in the brain. As en exemplar and source for the further study of behavioral phenomena, the book illustrates the scientific philosophy that Skinner and Ferster adopted: that a science is best built from the ground up, from a firm foundation of facts that can eventually be summarized as scientific laws.

Animal learning and human learning traditions have been distinguishable within psychology since the start of the discipline and are to this day. The human learning wing was interested in the development of psychological functions in human organisms and proceeded directly to their examination. The animal learning wing was not distinguished by a corresponding interest in animal behavior per se. Rather, the animal learners studied animal behavior in order to identify principles of behavior of relevance to humans as well as other organisms. The two traditions, in other words, did not differ so much on goals as on strategies. It is not by accident that so many techniques of modem applied psychol ogy have emerged from the animal laboratory. That was one of the ultimate purposes of this work from the very beginning. The envisioned extension to humans was not just technological, however. Many animal researchers, B. F. Skinner most prominently among them, recognized that direct basic research with humans might ultimately be needed in certain areas but that it was wise first to build a strong foundation in the controlled environment of the animal laboratory. In a sense, animal learning was always in part a human research program in development.