Is this your card?” says the street magician holding up the 5 of diamonds that you had carefully shuffled into a full deck just a moment ago.

You know there’s no real magic– it’s just a clever trick, drawing your attention away from the cards while the magician skilfully tucks your card out of sight. Even if you know how they did it, it still feels like magic.

You get shown a complicated collection of geometrical shapes arranged in a pattern that makes it appear as if the whole ensemble is moving.

But you know it isn’t.

It’s just a weird quirk of the visual system that overlays the movement even though there is none. And no matter how hard you try, you can’t stop your brain from making the illusion. Even when you know it’s an illusion, you can’t stop seeing it.

Knowing that our brains have a quirky way of seeing the world is not just fun and games. The gains of science have been built on a method designed to overcome some pretty powerful cognitive biases hard-wired into how we think. Decisions based on faulty reasoning or unexamined bias can cost companies millions and cause real harm to individuals. If cognitive bias is something bad for us, how did it come to exist in the first place? Cognitive bias comes from too much of a good thing.

Take for instance the Frequency Illusion:

You need to buy a new car, so you start looking at your options and settle on a blue Fiat which you hadn’t noticed much before but the mileage is really good. All of a sudden you start to see them everywhere! Is everyone suddenly buying blue fiats? No, you’re just noticing them now.

Our brains have to cope with a huge amount of information every second. To cope with all the data and minimise the processing load, our brains edit large amounts of information out as irrelevant. This is a vital survival mechanism. We simply would not cope if there was no filter.

Think about how the sound of a ticking clock can disappear into the background and you only notice it again when the ticking stops. Your brain has stopped paying attention to the ticking because it isn’t important. But when the ticking starts again, the change may be important so you pay attention.

Blue Fiats aren’t important until they are. Once they are, you’ll start noticing them everywhere. Similarly, if you believe you are lazy, chances are your brain is going to look out for evidence of your laziness. Once you believe it, you’ll start seeing it everywhere. But you’ll probably ignore the times when you were industrious.

Cognitive bias can be bad for your mental health, but it’s also bad for business. This Psychology Today article by Jim Taylor explores how irrationality impacts companies and what can be done about it.

Two vital bulwarks against cognitive bias in work-place decision making are:

  1. Collaboration: it’s easier for me to see bias in you than to see it in me. This is why we need each other. Collaboration helps us to check each other.
  2. Data: look for information that confirms and contradicts the assumptions in the room.

And then Daniel Kahneman’s book, “Thinking, Fast and Slow” provides in-depth explanations of how our brains work and how to mitigate the effects of bias. When guarding against bias, Kahneman suggests you look out for the following:

  • Self-interest – is the idea something that directly or indirectly benefits the person punting it?

  • Overconfidence – can the idea stand on its own merits or is the person punting it trying too hard?

  • Attachment to past experience – is the person motivating this idea on the basis of inertia?

  • Falling in love – is the punter of an idea providing anything other than a glowing review?

  • Groupthink – has anyone dissented? If not, why not?

Our brains can be a problem, but the glitchy software also presents an opportunity to teams and companies that want to make collaboration, mutual accountability and vulnerability fundamental values in their work.