John B. Watson (1878-1958), the behaviorist, thought there were three basic, inherited emotions: fear, rage, and love (Watson, 1924). He suspected that the wide variety of emotions experienced by adults had been learned. Proving his suspicion would be difficult because "unfortunately there are no facilities in maternity wards for keeping mother and child under close observation for years."

So Watson attacked the apparently simpler problem of showing that the emotions of fear, rage, and love could be distinguished in infants. (He recognized the difficulty of proving that these were the only basic emotions, and he made no such claim.) Fear could be elicited by dropping the child onto a soft feather pillow (but not by the dark, dogs, white rats, or a pigeon fluttering its wings in the baby's face). Rage could be elicited by holding the child's arms tightly at its sides, and love by "tickling, shaking, gentle rocking, and patting," among other things.

Here is an experiment reconstructed from Watson's conclusions. A child was stimulated so as to elicit fear, rage, or love. An observer then looked at the child and judged the emotion the child was experiencing. Each judgment was scored as correct or incorrect-correct meaning that the judgment (say, love) corresponded to the stimulus (say, patting). Sixty observers made one judgment each, with the results shown in the accompanying table. To find the expected frequencies, think about the chance of being correct or incorrect when there are three possible outcomes. Analyze the data with x² and write a conclusion.