The topic of stimulus control is too broad and complex to be traceable here. It would probably take a two-semester course to cover just the highlights of that field's evolution. The more restricted topic of equivalence relations has itself become so broad that even an introductory summary requires more time than we have available. An examination…

In this article, the author describes some of Fred Keller's characteristics that might help people to appreciate him even more than they already do, and in addition, might help them understand him not only as a scientist and teacher, but as a man. People often tend to forget that the most valued scientists, teachers, and career models are also men…