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Understanding the Factors that Shape Public Opinion

Person being influence by multiple people with loud speakers in their hands

We all like to think we make rational decisions based on the best available evidence, but all of us are subject to unseen influences. These include our social identity, friends, feelings, and even our own brains. All these factors can affect how we make decisions in our personal lives and in the public sphere.

Social Identity

Even though people have distinct personalities and life experiences, they are also influenced by their social identity. Social identity theory was coined by psychologist Henri Tajfel in the 1970s. Tajfel closely studied group dynamics. He theorized that social groups provide people with a sense of identity and self-esteem. He also noticed that once people identify with a group, they usually try to conform with other group members. Tajfel also recognized that people in social groups tend to categorize others as either belonging to the group (us) or outside of it (them). He found it is often the case that people within a group tend to look for negative aspects of those outside the group in order to elevate their own self perceptions.

Social Identity in Politics

Group dynamics play an important role in politics. On the macro level, there are political parties. In America, a majority of people (though not all) identify as being either Democrat or Republican. Then there are other groups such as veterans, African Americans, immigrants, women, men, the LGBTQ+ community, and so on. Research has found that people predict which political party will support the interests of a particular group at this level, then vote accordingly. For example, people interested in women’s rights will vote for the party that promotes policies for women. As a result, political parties usually seek to align themselves with various interest groups. Watch any campaign advertisement for the many visual references to veterans, ethnic groups, gun owners, etc. Social identity also plays a part in mobilizing people politically. One example of this is the work of AIDS activists who rallied the gay community to advocate for AIDS awareness and reform.

The Downsides of Social Identity

Although there are benefits to social identity, it does have a dark side. Social identity can lead to in-group bias, meaning people treat group members better than outsiders. This leads to division and prejudice. This bias affects everyone, including court judges. One study found judges in Israel to be more lenient with people belonging to their own ethnic groups. Other studies have found in-group bias can lead to aggression even between completely arbitrary groups. In the famous Robbers Cave experiment, a homogenous group of white, middle-class, Protestant 11-year-old boys were assigned randomly to one of two groups at a summer camp. The groups were asked to compete against one another in camp games like tug-of-war and baseball. Tension between the groups eventually escalated to the point that one group burned down the other’s flag, and the boys began stealing from one another. In the political arena, Democrats complain bitterly about Republicans and vice versa. The last decade in particular has been marked by increasing animosity and tension between the two groups. This is bad for democracy. Lawmakers are often locked in power struggles, unable to agree on policies. And tension between the sides has become so extreme that some have raised the possibility of another civil war.

Social Influence

Peer pressure doesn’t just affect teens. Even adults can find it difficult to go against the crowd. Psychologists believe this is partly because people fear rejection. Social groups provide physical and psychological support; the idea of being a social outcast is frightening. Researchers have also discovered that the pain of social rejection is actually similar to physical pain. Many people conform to save themselves this discomfort. Peers also provide social proof. People often feel insecure in their conclusions and feel validated when others share the same opinions. They will even change their perceptions to match others in a group setting.

Social Influence in Politics

These dynamics play out in politics just as they do in other areas of life. No one wants to be the one person at a dinner party disagreeing with everyone else. Research shows that people’s friends influence their political opinions. One study conducted at the Paris Institute of Political Studies in France found that friendship groups reduced differences of opinion as much as 30% in just six months. Many campaign advertisements show crowds of people supporting the candidate. This gives the impression that viewers would be in good company if they were to vote for Candidate X. Take, for example, this commercial for Senator Bernie Sanders with frequent shots of huge crowds supporting him. Today, people’s neighbors are likely to all lean more Democrat or Republican, depending on the area. Authors of a 2021 study out of Harvard University found that 98%-99% of Americans live in highly partisan areas. Democrats live close to other Democrats, and vice versa. When all your neighbors hold a certain set of beliefs, it’s more difficult to see a different perspective.

Emotional Reasoning in Politics

Although emotions help people make decisions, too many strong emotions make people less rational and more impulsive. According to research, different emotions have different effects.

  • Anxiety can prompt people to look for more information and can even prompt them to change their minds.

  • Fear often makes people seek safety. It also increases trust in the establishment, and drives them to come together to overcome a problem.

  • Anger makes people more willing to support risky political decisions. It also makes their voting patterns more habitual. Angry people are less likely to dig for more information on a particular topic. It can also inspire distrust of the government.

  • Enthusiasm can motivate people to become more politically active. Like anger, it also drives people to support more daring policies, and be more habitual in their voting.

Fun fact – a recent study found that fearful people are less likely to vote for the extreme right of the political spectrum, while angry people are more likely to do so.

Politicians attempt to use emotional reasoning to their advantage. Some research has found that emotional persuasion can be more effective than fact-based arguments. As a result, campaign advertisements are full of touching music and images of politicians hugging constituents and kissing babies. Political messages often seek to inspire a range of emotions including fear, anger, and enthusiasm.

President Trump played on the fear of Democrats destroying democracy in his speech on January 6, 2021. He said, “All of us here today do not want to see our election victory stolen by emboldened radical-left Democrats, which is what they're doing.”

He also inspired by saying, “We have overwhelming pride in this great country and we have it deep in our souls. Together, we are determined to defend and preserve government of the people, by the people, and for the people.” President Biden used similar tactics in a 2022 speech. He elicited fear of Republicans destroying democracy when he said, “Too much of what’s happening in our country today is not normal. Donald Trump and the MAGA Republicans represent an extremism that threatens the very foundations of our republic.” In the same speech, President Biden used language to inspire. He said, “Our task is to make our nation free and fair, just and strong, noble and whole. And this work is the work of democracy – the work of this generation. It is the work of our time, for all time.”

Cognitive Biases

People’s brains can also trick them in unexpected ways. There are a number of cognitive biases people have that influence their political beliefs and opinions. Confirmation bias and the availability heuristic are examples of this.

  • Confirmation bias means favoring information that fits into your world view and discounting information that doesn’t.

  • Availability heuristic is putting more value on information that comes to mind quickly, not which is most accurate.

Cognitive Biases in Politics

It isn’t difficult to see how these biases play out in politics. Confirmation bias makes Democrats and Republicans more likely to believe information that matches their beliefs. It also entrenches opinions, stopping people from changing their minds. Confirmation bias is also one reason people from opposite sides of the aisle sometimes feel they are living in different worlds – each group may be working with completely different sets of accepted and discarded information. The availability heuristic comes into play when candidates or leaders emphasize their messaging on a particular topic. Since this information is most recent, people will recall it first when making decisions.

The Takeaway

We are influenced by the groups we identify with, the people we interact with, our emotions, and cognitive biases. In order to make truly rational, independent decisions, it’s important to become aware of these influences. Once they are seen and understood, we can make better choices for ourselves and our society.

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