Back to Blog Listing

You don't know how much you don't know

How well do you understand a toilet flush? Your kettle? The fridge?

You pull a lever and water runs. You flick a switch and water boils. You open a door and it’s cold. We get these things; we use them every day. Right?

Rozenblit and Keil would tell you you’re wrong

In 2002, they asked participants in their study to rate their understanding of everyday items like those ones. Most people rated themselves pretty high – seven out of sevens all round.

I’m sure you can see what’s coming. Rozenblit and Keil then asked the participants to write an explanation of each item. The group uhhmed and ahhed, then went back to their scores and unanimously marked themselves down. Way down.

This is called the Illusion of Explanatory Depth

It says that we significantly overestimate our knowledge of specialist subjects. And it goes beyond household objects. They ran the experiment on the economy, scientific concepts, religion. Again and again, people believed they understood the area well, but found themselves unable to explain it.

Twin the Illusion of Explanatory Depth with its partner bias, the Curse of Knowledge, and you start seeing how specialist fields – medicine, tech, law, finance – are known for their complexity. We underestimate what we don’t know, and we can’t explain what we do know. So what do we do? We rely on linguistic crutches.

We use these crutches like get out of jail free cards

Just last week, I was explaining the Flesch Kincaid readability score to someone. I use this score every day. I’ve probably explained it hundreds of times before. If you asked me to rate my understanding of it, I’d almost certainly give myself full marks. Heck, you could probably call me a readability ‘subject matter expert’ - oh, the glamour.

So I trotted out my usual spiel: ‘it takes your text, analyses the number of long words and sentences you’re using and spits out a number. The higher the number, the easier your writing is to read.’

‘So what’s the specific formula it uses?’ The other person asked. ‘Is that number a percentage of the whole piece? And why does the score correlate inversely?’

Reader, I was stumped.

Luckily, my brain jumped to attention: ‘oh, yeah. That’s just the algorithm. It works all that out.’

Does Flesch Kincaid use an algorithm? Nope. Do I really understand what an algorithm is? Probably not. I was challenged on a subject I thought was my specialism. I didn’t understand it as deeply as I thought I did, so my brain skimmed over it and answered with a crutch: algorithm. The shame.

And it’s not just me (I promise)

If you’re trying to explain how a cloud network works, you might use crutches like ‘economies of scale’ or ‘agile working’. If you’re tasting wine, you might mumble something about ‘legs’ or ‘tannins’. If you’re trying to build a happy office, you might throw in ‘employer brand’ or ‘culture change’. In this information age, we have a surface level knowledge of so many subjects, our brains have developed these crutch words as short-cuts through topics too complex to deeply grasp.

So what are yours?