If you ever felt your motivation drain away under a micromanaging boss, he gave you the language for what was happening to you. If you ever sensed that grades and gold stars were somehow diminishing the very learning they were supposed to enhance, he explained why. And in doing so, he helped liberate psychology from one of its most limiting assumptions. The Black Box of Behaviorism For much of the 20th century, the dominant paradigm in psychological research, behaviorism, treated humans as input-output machines.