A traveling salesman visits and tells people that the wave of his hands can cure their paralysis of the legs. He demonstrates his ability by magically telling the crowd about the patient, waving his hands, and then showing that the patient can stand on her feet. The crowd cheers and offers to pay for their healing. They forgot to realize that scientists can disagree. They forgot to compute the average pain score.
Several psychologists get together and discuss why it is that people help each other.
He selects 40 2-year olds who have never eaten peanut butter. Half are forced to eat 2 tablespoons of peanut butter a day for 14 days. Half are forced to eat 2 tablespoons of a placebo a day for 14 days. Skippy assesses their ability to identify colors before and after the 14 days. The number of successful answers of to 20-point test was tallied and their gain scores reflected their ability.