We often receive information about alleged benefits or harms of existing or possible states of affairs. We may be told that North Korea has missiles that can reach the United States or that carbon sequestration and storage is a viable strategy for preventing climate change. How do we determine whether such information is credible?

One basic principle is that “bad is stronger than good.” We are more likely to pay attention to and remember negative information than positive information. The costs of mistakenly believing hazard information, unnecessary precautions, are much lower than the costs of mistakenly disregarding such information, which may include injury or death. There is no such asymmetry between the costs of mistakenly accepting or dismissing positive information. We are more vigilant toward hazards because the stakes are higher.

This is related to the principle of loss aversion in decision making. We consider losing $1000 to be a more negative outcome than gaining $1000 is positive. The larger the amount, the greater this disparity. According to Kahneman, loss aversion is a product of our evolutionary history: “Organisms that treat threats as more urgent than opportunities have a better chance to survive and reproduce.”

In 2014, the journal Behavior and Brain Sciences published a target article by political scientist John Hibbing and two colleagues presenting research suggesting that conservatives are more physiologically and psychologically responsive to negative information than liberals. This negativity bias causes conservatives to prefer stability rather than change, which can be seen as threatening. The article was followed by 26 commentaries by social scientists, most of which questioned details of Hibbert’s argument, but did not seriously challenge its basic assumptions.

A new article by Daniel Fessler and others explores the implications of negativity bias (or threat bias) for information processing. They conducted two separate, but similar, studies involving a total of 948 participants recruited through the internet. Particpants read 16 statements, half of which claimed the existence of a benefit while the others claimed to have identified a hazard. The majority of the statements (14 of them) were false. Here are two examples.

1. People who own cats live longer than people who don’t.
2. Terrorist attacks in the U. S. have increased since September 11, 2001.

Respondents were asked whether they believed each statement on a 7-point scale ranging from absolutely certain the statement is false to absolutely certain it is true. They were also asked judge the magnitude of each benefit or hazard on a 7-point scale running from small to large. (The benefit and hazard items had been matched in magnitude on the basis of previous testing.) The authors created an index of credulity by multiplying the judged truth of the statements by the magnitude of their benefit or hazard. Negativity bias was computed by subtracting the credulity of the eight benefits from the credulity of the eight hazards.

The authors constructed a summary measure of liberalism-conservatism combining input from four measures: an issues scale asking them to evaluate 28 political concepts, i.e., gun control; a social principles index asking them to choose between 13 social principles, i.e., punishment vs. forgiveness; self-ratings on a 9-point liberalism-conservatism scale; and political party affiliation.

Replicating Fessler’s previous research, they found that, for the sample as a whole, hazards were rated as more credible than benefits. As they predicted, there was a positive relationship between conservatism and this negativity bias. Breaking the effect down, they found that conservatives rated hazards as more believable than liberals, but there was no difference between liberals and conservatives in the credibility of benefits.

Of the four components of the conservatism measure, the issues index accounted for greatest portion of its relationship to negativity bias. This index contained three types of items: social conservatism, i.e., school prayer; military conservatism, i.e., drone strikes; and fiscal conservatism, i.e., tax cuts. As shown in the chart below, only social conservatism was strongly related to negativity bias. Fiscal conservatism was unrelated to it, while the relationship between military conservatism and negativity bias was positive but not statistically significant.

(For you statistics nerds, in these charts, the small squares indicate the sizes of the correlations and the lines indicate the confidence intervals. If the line crosses zero, the relationship is not statistically significant. Study 1 is on the left; Study 2 on the right.)

It is impossible to state, in the abstract, whether conservatives have a better strategy than liberals for processing information about potential hazards. If we had independent evidence suggesting that the hazard information were true, the conservative strategy would be more rational, while the liberal approach would be more sensible if the information were known to be false.

We can say, however, that their negativity bias leaves social conservatives vulnerable to alarmist rhetoric such as candidate Donald Trump’s often repeated claim that the homicide rate in the U. S. is the highest it has been in 45 years, or his attempt to publicize crimes committed by immigrants.

In a previous post, I reported that conservatives are more likely than liberals to rate syntactically correct but meaningless statements—technically known as “bullshit”—as profound. There is also evidence that conservative websites contain a higher percentage of “fake news.” It would be interesting to know how many of these fake news stories report alleged threats to people’s well-being. There may be a pattern here.

Much of today’s most alarming rhetoric deals with threats of terrorism. Since 2001, an average of 40% of Americans report that they fear they will be victims of terrorism. The actual probability of perishing in a terrorist attack—about one in four million per year—contrasts favorability with more prosaic dangers such as being killed in an auto accident or drowning in the bathtub. Fear of terrorism imposes enormous financial and social costs on our society, way out of proportion to the actual threat. These fears are ripe for exploitation by politicians. How much freedom have Americans already surrendered in the name of false security? As Timothy Snyder notes in On Tyranny, “It is easy to imagine situations in which we we sacrifice both freedom and safety at the same time: when we . . . vote for a fascist.”

You may also be interested in reading:

Bullshit: A Footnote

Publicizing “Bad Dudes”

Are the Terrorists Getting What They Want?