There are many candidates in the 2011 American race to be the Republican Party presidential nominee. Most of them, such as Texas governor Rick Perry, deny that current increases in world temperature are the result of human activities that produce heat-trapping gases. Instead, they argue that climate change is just a matter of natural fluctuations, so no steps need to be taken to restrict industrial activities such as oil production that increase the amount of greenhouse gases in the atmosphere. This denial contradicts the conclusions of many scientific researchers summarized by the Intergovernmental Panel on Climate Change.
If the scientists are right, the consequences of failing to act to reduce global warming will be enormous, including massive flooding of coastal areas and weather extremes such as droughts. Why and how do leaders in the US and other countries such as Canada deny that global warming is a problem that needs to be addressed by restricting carbon emissions?
Scott Findlay and I recently published an article in which we explained climate change denial as resulting from a natural thinking tendency called motivated inference, in which beliefs are based on people's goals and emotions rather than on good evidence. All of us are prone to motivated inference, in situations such as these:
Romantic relationships: my lover treats me poorly, but he/she will change.
Parenting: my child hates school, but will settle down and straighten out eventually.
Medicine: this pain in my chest is indigestion, not a heart attack.
Politics: the new leader will be the country's savior.
Sports: our team has been losing, but we're going to play great today.
Law: the evidence against my hero is serious, but he couldn't have done it.
Religion: life is hard, but my caring God will lead me to eternal bliss.
Economics: this rapid economic growth is a sign of a new kind of economy, not a bubble.
Research: the article I'm writing is my best ever and will get into a top journal.
Motivated inference is not just simpleminded wishful thinking, in that motivations do not lead directly to beliefs. Rather, our goals lead us to acquire and consider information selectively, so that we manage to find some evidence that makes us think we are being reasonable in maintaining an emotion-based belief that we ought to doubt.
The motivations that encourage politicians such as Rick Perry to deny human-caused global warming are clear: they don't like government intervention in the economy in general, and in particular they don't like interference with the oil industry, a major source of carbon emissions. If global warming is a serious problem, then there needs to be massive actions by governments across the world to change people's energy practices that produce greenhouse gases. Oil company executives and allied politicians do not want to see such actions take place, so they make various kinds of maneuvers to undermine scientific conclusions: research is flawed, global warming is just natural fluctuation, and so on.
Hence psychology is very useful for explaining why politicians and other people continue to hold beliefs that are contrary to the available evidence and to the interests of billions of people. It is less obvious what can be done to overcome denial of a world-threatening problem. Providing more evidence that global warming is accelerating as the result of human carbon emissions is only part of a solution. We also need to convince people that the needs of the vast majority of the world's people are more important than the interests of an industrial minority and the anti-government ideology that supports them. Overcoming motivated inference requires recognizing and changing motivations.