When surveys like the one this week by the Pew Research Center show major disagreements between scientists and the public on issues such as global warming and genetically modified foods, there is usually a lot of hand wringing that Americans seem to be so scientifically illiterate.
But Yale Law School professor Daniel Kahan said his research shows that isn’t true.
Mr. Kahan is a member of the Cultural Cognition Project, which his website describes as a group that uses “empirical methods to examine the impact of group values on perceptions of risk.”
He has found that when people are deeply divided over issues such as climate change or natural gas fracking or evolution, it’s not because they are scientifically ignorant. In fact, he has found that the more knowledgeable such people are about science, the more polarized they tend to be on hot-button issues.
Still, the Pew report released Thursday showed sizable differences between the 2,002 American adults surveyed last year and the 3,748 scientists who belong to the American Association for the Advancement of Science.
More than eight out of 10 scientists believe humans are the main cause of climate change; that animals should be used in research; that genetically modified food is safe to eat; and that humans have evolved over time. The public’s support for those views ranges from 37 percent on genetically modified foods to 65 percent on human evolution. Why such a gap?
The first thing to recognize, Mr. Kahan said, is the split shows up only on a limited number of controversial issues in America.
Most of the time, he said, people accept the scientific consensus, whether it’s the benefits of pasteurized milk and fluoridated water or the necessity of medical X-rays. And when some protest fluoridation or pasteurized milk, he added, they are seen by most people as fringe believers.
Still, some believe the public doesn’t grasp exactly how science works.
John Radzilowicz, director of professional development for ASSET STEM Education in Pittsburgh, which trains science teachers, believes “the public doesn’t have an understanding of the nature of science. They don’t understand that science produces results that are reliable, but tentative, and that then plays into a whole bunch of other factors.”
That uncertainty about how scientists think can be further distorted by lobbyists and special interest groups, he said. “On global warming, for instance, you’ve got these huge efforts being made by the fossil fuel industry” to influence people’s views. “They know people don’t understand how science works, and they can play on that.”
There are two theories on why the scientists in the Pew survey had different views than the public.
One is that scientists as a group tend to be politically liberal, and their views are likely to reflect those biases. J. Brian Balta, a visiting geology professor at the University of Pittsburgh, said that may explain why the scientists in the Pew survey were more likely to oppose offshore oil drilling than the public.
The other possibility, Mr. Kahan said, is that scientists have a better idea who the experts are in certain fields and pay attention to their views.
Nonscientists who are loyal to a particular political party or religious group won’t know the experts as well, so “they credit the views that scientists have only when they fit with what their affinity group believes.”
Despite their divergent views, the public told Pew researchers they strongly support scientists and the work they do, and a strong majority favors federal investment in research.
As a result, said Lee Rainie, co-author of the Pew report, scientific leaders in America “believe that rather than retreating from a place where the public is not in agreement with them, they need to build on the good will people have toward science in general to talk more with people to make their case.”
First Published: January 29, 2015, 6:59 p.m.
Updated: January 30, 2015, 5:03 a.m.