You walk into your first yoga class. You’re a little insecure about your weight and how your yoga clothes cling to your body revealing every flaw. You’re nervous about making a fool of yourself.

Your eyes instantly zoom onto the fit model-esque people chatting in the corner. As you walk past them, your ears pick up the tinkle of laughter. My god, are they laughing at me?

You pick a spot in the back of the classroom where no one can see you. The teacher asks everyone to get into crouching fish pose. Do people know this pose?

You flail around on your mat and fall over in a big thump.

You look up to make sure no one saw you. Crap. The guy next to you is hiding a smirk. I KNEW IT. Everyone is laughing at me.

You avert your gaze after class, run out of there and vow to never do yoga again.

Confirmation bias strikes again

In the yoga class, you looked for instances that confirmed your insecurities — the models who were laughing at you, the guy who smirked when you fell.

You ignored other instances that didn’t prove your insecurities — basically everyone else in class who barely took notice of you.

Confirmation bias is the human tendency to seek, interpret and remember information that confirms your own pre-existing beliefs.

It is insidious. It affects every choice you make. Every. Single. Day. The things you choose to buy, your health, who you choose to marry, your career, your emotions, and your finances. It all happens in the background without you noticing.

How does confirmation bias work?

Confirmation bias affects you in 3 ways:

1. How you seek information

Confirmation bias affects how you look at the world around you.

When you’re alone at home feeling lousy, you immediately jump onto Facebook or Instagram. You look at pictures of people traveling, partying, getting married and think everyone I know is living a great life. You say to yourself, “I am such a lonely loser.”

You sit at home and feel crappy — all because you chose to seek information that confirms your crummy feelings. You knew looking at those photos would make you feel worse but you sought them anyway.

2. How you interpret the information in front of you

Confirmation bias also affects how you process what is otherwise neutral information — and it tends to favor your beliefs.

When you are falling in love, all you see in your partner is a beautiful, perfect Adonis. You don’t notice a single flaw. When that relationship sours, all of a sudden, all you see are flaws — their coffee breath, their penchant for droning endlessly about a topic you don’t care about, the hairs they leave in the sink.

You are dating the exact same person, but you perceive the things they do differently based on how you feel.

3. How you remember things

Even your memories are affected by confirmation bias. You interpret and possibly even change memories and facts in your head based on your beliefs.

In a classic experiment, Princeton and Dartmouth students were shown a game between the two schools. At the end, Princeton students remembered more fouls committed by Dartmouth, and Dartmouth students remembered more fouls committed by Princeton.

Both groups of students fundamentally believed their school was better. So they tended to remember and recall more instances that showed their school in a good light and the opposing school in a bad light.

Why am I like this?

You seek evidence that confirms your beliefs because being wrong sucks. Being wrong means you’re not as smart as you thought. So you end up seeking information that confirms what you already know.

In a famous experiment, when participants were presented with evidence counter to their political beliefs, areas of their brain associated with physical pain became more active — it’s as if being wrong physically hurts.

It’s easy to accept opposing views when it concerns things you don’t care about. But you also have deep seated beliefs that form a core part of your identity (e.g. that you’re a kind person, that your political views are correct). Evidence that runs counter to these beliefs often causes cognitive dissonance — a feeling of immense stress and anxiety.

Cognitive dissonance triggers a fight or flight response — you either dig in your heels and double down on your existing beliefs (fight) or get away from the opposing fact (flight).