What do a trio of tiny pigs, the slogan of the French Republic and the Olympic Motto all have in common?

It’s the number three.

Over the years people have asked me if I have a weird obsession with the number three. It pops up a lot in my work. But there’s a really good reason.

Every single successful tone of voice I’ve done has been three words, with three writing techniques under it. I’ve tried other ways. They just don’t work.

For a few years, I worked on instinct, knowing that people found three things easy to remember. And because it was working so well, I kept doing it.

Then I got curious. Why is the number three so powerful and why are there patterns of three wherever you look?

There’s a really simple explanation.

Our brains are hard-wired to look for patterns. That’s because the world is a chaotic and busy place and our brain tries to help us out by looking for and finding patterns. It makes decision making and learning much easier. And research over the last few years has shown patterns are really important in how we learn language.

Three is the lowest number we can form patterns with and the ‘rule of three’ is an idea that’s been around for a long time. There’s even a Latin phrase “omne trium perfectum” which means everything that comes in threes is perfect or complete.

Early research suggested our working memories could handle quite a lot of things, up to seven. But the truth is it’s a lot lower when we’re not using clever tricks like grouping things together or repeating things so they stick in our heads. It’s why you can remember two or three things on your shopping list but you probably can’t remember a number in your mobile that you only dial occasionally.

The reality is we can probably hold around 3-5 things in our working memory, so when we’re creating tone of voice as part of a language strategy project we stick to the magic three.

Remember (!) it’s the lowest number we need for a pattern and it’s the most memorable.

Every so often I’ll accidentally test my own theory, just to check something hasn’t changed! Right now I’m working with a big bank on a language strategy project. We developed a three-word tone of voice that was sticking easily and spreading fast. And I also developed a model of empathy alongside it, how everyone should behave for a great customer experience.

The only problem was it had 5 things, and a lot of detail. And it quickly became clear people couldn’t remember all the elements. If you’re trying to change your culture, your language or quite frankly anything in your organisation, then it won’t work if people can’t remember it. So we revisited the model and aligned it with the three elements of the tone, now it’s easy to remember and so the behaviours are more likely to stick.

The next time you send something check how many elements it contains. Is your letter asking people to do six things? Is your new tone of voice so complicated it won’t stick? Would just three things make it oh so memorable?

I’d love to know if you’ve got down to your magic three, if you have then drop me a line.