#27: Conjunction Fallacy

Bias number 27 is known as the conjunction fallacy. This is a cognitive bias that arises when we make assumptions about the occurrence of more than one condition, such as a personality trait.

For the statisticians amongst us, this is an interesting cognitive bias because it assumes that specific conditions are more probable when they occur together over the occurrence of a single condition. This is statistically improbable, and yet our thought processes, relying less on fact and more on assumption, will infer otherwise.

How does this work in practice? Imagine that someone tells you they grew up in Lancashire. You might infer that, because Lancashire is known for ale, potato pie and rugby league, this person will regularly drink ale, eat potato pie and support their home rugby league team.

Is this true? To get a real answer to that question, you’d have to survey every person who has ever grown up in Lancashire. No mean feat, right?

You could challenge this assumption by asking the people in your life who grew up in Lancashire what their habits with regard to ale, potato pie and rugby league are. Unless you are surrounded by ale-drinking, potato-pie-eating rugby league players, I would hazard a guess that pretty soon you’d discover this is not the case.

I know. I live with a Lancashire-raised chap who feels a nostalgic fondness for certain ales and potato pie and will watch rugby league when there is no other sport on telly. However, given the choice, he would eat rib of beef with triple cooked chips, washing it down with a glass or several of Malbec while on lunch break at the Oval every time.

Just sayin’.

You could say that the conjunction fallacy is a source of the tendency to stereotype people. We jump to conclusions about people, creating stories about who we believe them to be based on a single piece of information. It seems unfair, and yet we still do it.

Why does the brain create stereotypes in the first place?

It’s about an attempt to create efficiency in processing information. If you’ve met one person from Lancashire who fits the above description, or perhaps you’ve watched a documentary about rural Lancashire, your brain may jump to the conclusion that ALL people from Lancashire fit that description.

However, it would be a major mistake in your cognitive processing. The easiest way to prove it is to ask a variety of people from Lancashire the question.

Survival itself, according to the brain’s wiring, is a risky business. The aspect of survival that makes it most risky is uncertainty. The brain will do whatever it takes to mitigate anxiety-provoking uncertainty by creating links between characteristics in people to reduce the fear.

Let me be clear. We are examining the lowest level of brain functioning in a human being when we consider the survival brain. For the most part, it does its job and it does it well. If you’re reading this article, consider that your neurology has got you this far in life. You can be grateful for it.

However, while we can appreciate it for the role it performs, it is important to recognise its tendency to take over. This is easily done because the survival function of the brain reacts most strongly and quickly to information. So, for all its benefits, this part of the brain is not interested in issues like truth or facts or exploration. This area of the brain’s only function is to keep you alive. It responds to threats, whether real or imagined.

Ironically, one of the biggest threats to a survival-coded brain is uncertainty, in particular uncertainty in people. People are unpredictable. People have minds of their own. People have their own survival stories that cause them to react in ways with which we are unfamiliar.

In short, according to the survival side of the brain, people are scary.

But are they really? Is it appropriate to live in fear of other people? And is it appropriate to make up stories about people based on false assumptions, just so you can create an experience of safety for yourself?

In moments like this, I recommend that you challenge your assumptions by looking for and analysing facts. Refuse to take things, especially your own assumptions, at face value. Instead, ask questions that reveal truth. Hear what someone says and observe their behaviour. See if their words marry with their actions. Observe. Exercise curiosity about reality.

Apply the same process to yourself. Do you inappropriately make assumptions about yourself based on the conjunction of qualities that are, in truth, mutually exclusive? What impact does it have on you? What would happen if you separated these qualities out and assessed them according to their individual merits? What might you find?

What you might find is that, as well as constraining others in pigeonholes by incorrectly assigning them traits, you are pigeonholing yourself. In doing so, you limit what’s possible for you in your own mind. When you limit yourself in the mind, you limit what’s possible for you in the world.

To liberate yourself, remove the shackles of this self-created prison by challenging your assumptions. And the first assumption to challenge is this: curiosity killed the cat. Living by this idiom keeps you in the dark about the truth, which is that cats rarely come to harm because of their curiosity. In fact, curiosity is what has kept them alive throughout the ages.

I invite you to exercise curiosity wherever and whenever possible. Not only will you reconnect with your natural cat-like playfulness, you'll bring playfulness to your engagement with other people.

At a time of great uncertainty, we could all benefit from exercising curiosity. And who knows? You might discover a new-found sense of brilliance in other people when you do.

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