We humans are a strange sort. We picture ourselves as the smartest animals on the planet, guided more by reason and critical thinking than impulse. But then why, many scientists continue to ask, do we so often believe in nonsense?
Instead of looking for what's good in our fellow travelers, we tend too often to look for what's bad. And in these days of instant global communications, easily accessible to the masses, lies and smears can spread at warp speed.
Nowhere is that more obvious than in the political arena. It's curious that we elect those who must guide our collective destinies not on the basis of who we like, or who we trust, but who we dislike the least. No wonder smear campaigns often work, because so many are so willing to believe the worst about someone, even in the total absence of evidence.
It's a daunting challenge for any scientist to explain why.
Psychologists at four universities pooled their efforts in an ambitious attempt to answer that.
They conducted four experiments at the University of Arizona -- three before the last presidential election, and one after -- and found that voters are more likely to believe an obvious falsehood about a candidate if that candidate is perceived as different from themselves. And they are much more likely to believe it if they are supporting a different candidate, which may not seem all that surprising.
But even a subtle hint that one candidate was somehow different had a dramatic impact on the believability of smears, according to Spee Kosloff, lead author of a study published in the Journal of Experimental Psychology: General.
Kosloff worked with fellow psychologists at Michigan State University in East Lansing, the University of Arizona, the University of British Columbia and the University of Leiden, The Hague.
"We found that when individuals see themselves as somehow categorically different from a political candidate, that opens up their motivation for bias against them," Kosloff said in a telephone interview. "Consequently, it motivates them to link attributes they fear or dislike to that candidate."
The research involved 365 politically active college students who were not informed of the purpose of the experiments until later. At issue were two smears, which the investigators labeled "lies," that persisted throughout the last presidential election: that Barack Obama is a Muslim and John McCain is senile.
Kosloff said calling someone a Muslim is not in itself a smear, because in this country citizens are free to practice any religion, or no religion at all, but in the context of a presidential election it is clearly a smear because many voters would not even consider voting for a Muslim, even though they are electing a president, not a pastor. And McCain, who was 72 at the time of the first experiments, was a fully functioning member of the U.S. Senate. The fourth experiment also centered on the allegation that Obama is a socialist.
The students were asked to rate the "likelihood" that a statement was true on a sliding scale from zero to 100 percent.
Here are the findings: