Finding Jack Michael's Footprints in the Sand.

Jack Michael left a legacy of fine discriminations among technical terms, a careful parsing of theoretical concepts, and a variety of behavioral interpretations of complex behavioral phenomena. When pushing into relatively unfamiliar territory in areas such as "memory," automatic reinforcement, multiple control, and additivity of response strength, I have been surprised and delighted to find evidence that Jack had once explored the same topics, in the same way, and had come to the same conclusions toward which I was groping.