Only 48 percent of respondents agree with the proposition that humans evolved from other beings, according to the General Social Survey, a broad survey of American attitudes and beliefs. But when the question is prefaced with the qualifier “according to the theory of evolution,” agreement with the proposition rises to 72 percent.

Responses aren’t necessarily driven by ignorance. “Where there is a sacred value that empirical science contradicts,” science will have trouble making headway, notes Jonathan Haidt, a social psychologist at the Stern School of Business at New York University.

And the value doesn’t even have to be sacred.

A few years back, Dan Kahan of Yale Law School, Hank Jenkins-Smith of the University of Oklahoma and Donald Braman of George Washington University Law School performed experiments testing how values affected people’s agreement with scientists about climate change, the disposal of nuclear waste and allowing concealed possession of handguns.

“The problem, it seems, is not that members of the public are unexposed or indifferent to what scientists say,” they concluded. “They disagree about what scientists are telling them.”

People identified as more egalitarian and more open to government interventions to address social ills — the left, as it were — were much more likely to say that most scientists agree global warming is happening and that it is caused by human activity. Most also said scientists either disagreed or were divided on the safety of storing nuclear waste.

On the right, people identified as individualistic and wary of Big Government responded differently: In their view, the scientific consensus said the opposite. How could they think that? They manufactured the expert consensus they wanted by defining as experts only those who agreed with their ideological position.

It is not hard to figure out the biases. People on the right tend to like private businesses, which they see as productive job creators. They mistrust government. It’s not surprising they will play down climate change when it seems to imply a package of policies that curb the actions of the former and give a bigger role to the latter.