Thus began the most notorious historical period in psychology, called behaviorism. Emotions were redefined as mere behaviors for survival: fighting, fleeing, feeding, and mating, collectively known as the “four F’s.” To a behaviorist, “happiness” equaled smiling, “sadness” was crying, and “fear” was the act of freezing in place. And so, the nagging problem of finding the fingerprints of emotional feelings was, with the flick of a pen, defined out of existence.
