You might think that you are most inclined to be affected by experts who agree with you. After all, there is a lot of research on that suggests that we tend to focus on information that confirms our hypotheses about the world.

An interesting paper in the January, 2012 issue of and Social Psychology Bulletin by Jason Clark, Duane Wegener, Meara Habashi, and Abigail Evans suggests that the opposite may be true.

Their proposal is that when an expert expresses an opinion that disagrees with your own, your own beliefs are threatened. At the same time, you believe that experts are probably going to make strong arguments in favor of their position. So, you pay careful to experts who disagree with you, presumably so that you will be ready to rebut their opinion. Paradoxically, then, you may be most strongly influenced by the opinion of experts who disagree with you.

To test this idea, participants did a broad survey on a series of topics, one of which was their attitude about taxes on sugary drinks. Then, participants read an opinion in favor of taxing sugary drinks. Some people were told that this opinion came from an expert in food and . Others were told that it was written by a high-school student. Finally, the opinion itself consisted of arguments that were judged in a pre-test to be strong or arguments that were judged to be weak. After reading the arguments, people rated their attitude toward taxes on sugary drinks.

People who did not believe in taxes on sugary drinks were hearing opinions that did not fit with their initial opinion. For these people, hearing a strong argument by an expert increased their attitude toward taxes significantly, while hearing a weak argument by an expert decreased their attitude significantly. Hearing an argument by a non-expert did not affect their opinion much.

The opposite pattern occurred for people hearing a message that agreed with their previous opinion. In this case, the strength of the expert argument had little influence on their attitude. However, hearing a weak opinion expressed by a non-expert led to a significant decrease in their argument.

That is, people seemed to pay quite a bit of attention to experts when the expert disagreed with them, but actually paid more attention to non-experts when listening to someone who agreed with them. A second study demonstrated that this effect was best explained by people's expectation that experts would provide good arguments.

I found this result to be both hopeful and cautionary. On the hopeful side, it looks like we have some tendency to grapple with arguments from people who disagree with us. That means that all of us have some capacity to change our opinion.

On the cautionary side, though, the modern world has given us an abundance of choice in the opinions we choose to hear. That is, while we can learn from people who disagree with us, we don't necessarily like to hear what they have to say. When given the choice, most people would rather listen to others who agree with them rather than disagreeing.

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