You probably have strong opinions about all kinds of things: like whether Coke is better than Pepsi, which football team deserves to win the Super Bowl, or which Chris is the dreamiest movie star—Pratt, Pine, Hemsworth, or Evans.

Why are there so many Chrises? But are all those opinions really yours?

Humans are social creatures. And when we talk about anything from TV shows to politics, lots of psychological phenomena come into play. Sometimes, this can lead to bad judgments and biased opinions.

But by knowing how your thoughts can be swayed, you can recognize it when it's happening— and maybe stop it. One kind of bias can come from the company you keep. It's normal to be friends with people who have similar opinions and values.

But many studies have shown that when you talk with people who feel similarly about things, you can end up with even more extreme opinions. In other words, you get polarized. For example, some experiments have asked people to decide on a risky business proposition together, and found that groups of risk-takers get even more risky, while risk-avoiders get less risky.

But it's hard to escape polarization: it can also happen when you have strong opinions that are challenged by others. One study in 2011 had people with diverse views on a social issue respectfully discuss their opinions. Those who already had more extreme beliefs, both for and against the issue, showed even more polarization afterwards.

This is called a boomerang effect, where a counter-argument makes someone believe even more strongly in their original judgment. Researchers think this is partly due to your social identity: the fact that your beliefs and the groups you belong to are part of who you are, so you defend them. So if you and your friends are die-hard peanut M&M fans, hearing a case for crispy M&Ms could just make you extra defensive of your peanut-loving identity.

I know it does that to me. Another way your opinions can be swayed in a debate has to do with what you think of first— because that can act as an anchor, basically a starting point, for the rest of your thoughts. One study in 2000 involved taking an old car to 60 car experts, including mechanics and car dealers.

The pretend-customer told the expert what they thought the car was worth, either higher or lower than it actually was, then asked for the expert's judgment. And the initial suggestion affected the experts' estimates, making them similarly higher or lower. Psychologists think this is partially due to selective accessibility, where an anchor makes some information more available in your mind, which affects your opinions.

For example, a small study in 2010 even found that when it was warmer outside, or people were simply asked to think about hot things, their responses to survey questions showed that they believed more strongly in global warming. So if you stumble upon a flame war online, for example, the first thing you read in the comments could cause selective accessibility and shape your thoughts— although there hasn't really been research into that kind of anchoring. Your opinions can also be influenced when you're trying to make a decision with a group because of something called groupthink, which can make you blind to bad reasoning.

Let's say you're a Doctor Who fan and enter a heated debate after someone influential claims that, hands-down, Matt Smith's Eleventh Doctor is the best one. A discussion begins with that anchor, filled with a bunch of pro-Matt Smith arguments. Maybe you're more of a Tom Baker fan and you think that bow ties just aren't that cool, but you keep your mouth shut in self-censorship, figuring that other people won't want to hear your opinion.

You might notice that any arguments that other Doctors might be better are rationalized by the group, meaning that they are dismissed as bad arguments. Or people might stereotype David Tennant's fans, saying they only liked him because of his looks, and ignoring their opinions. After lots of key smashing back and forth, it seems like everyone agrees that Eleven is the best, but that's not necessarily true— it's what psychologists call an illusion of unanimity.

And when people think everyone agrees, they're more likely to adjust their opinion. When deciding on anything, from government policy to a group project at school, all of these and other characteristics of groupthink can influence decisions and shut down critical debate. So ... it might seem like your opinions aren't ever really yours.

But there are ways to fight against the influence of polarization, anchoring, and groupthink. Essentially, it all comes down to critical thinking, and considering why your opinion might be wrong or too extreme, not just why it might be right. Some studies have found that having someone play the Devil's Advocate can help, genuinely arguing against the preferred decision and asking thoughtful questions.

But an extreme counter-argument can also backfire and cause the boomerang effect. Other research has shown it can help to talk with others outside of your group, and listen to diverse opinions. You might discover that what you thought was normal actually was an extreme stance, or that the issue is more complex than you thought.

Also, you can learn about something or start a group discussion before forming a strong opinion— like, reading a bunch of news articles for yourself before reading the comments or tweet-storms about them. We're all naturally influenced by the people around us— it's unavoidable, and it isn't necessarily a bad thing. But by being aware of bias and potentially bad choices, you can take back some control and know that it's okay to speak up, disagree, and change your mind.

After all, we're all learning here. But peanut M&Ms are the best. Thanks for watching this episode of SciShow Psych, brought to you by our patrons on Patreon!

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