Psychological Science The Need for Psychological Science. The Limits of Intuition. Hindsight Bias We tend to believe, after learning an outcome, that we would have foreseen it the “I-knew-it-all-along” phenomenon Overconfidence We tend to think we know more than we do Heuristics
The Need for Psychological Science
In the early twentieth century, thousands of Americans in the South died from Pellagra, a disease marked by dizziness, lethargy, running sores, and vomiting.
Finding that families struck with the disease often had poor plumbing and sewage, many physicians concluded that pellagra was transmitted by poor sanitary conditions.
In contrast, Surgeon General Joseph Goldberger thought that the illness was caused by an inadequate diet.
He felt that the correlation between sewage conditions and pellagra did not reflect a casual relationship, but that the correlation arose because the economically disadvantaged were likely to have poor diets, as well as poor plumbing.
So, how was the controversy resolved?
Well, the answer demonstrates the importance of the scientific method.
To prove he was right, Goldberger not only had himself injected with the blood of a victim with sores all over his body, he found a victim with diarrhea and….ate his excrement!
He did NOT come down with pellagra!
To further make his case, Goldberger asked two groups from a Mississippi state prison farm to volunteer for an experiment. One group was given a high carbohydrate, low protein diet that Goldberger suspected to be the culprit, while the other received a balanced diet. Within months, the first group was ravaged by pellagra, while the second showed no signs of the disease.