I was about to go for a swim in a Stockholm lake when I passed a middle-age couple getting out of the water.

“Is the water cold?” I asked them.

“Twenty-two,” the man responded.

Twenty-two? Twenty-two?! That's a number, not an answer. And how was he so precise, anyway? How did he know it wasn't 23 or 21? There was no thermometer in the water, I made sure to check later.

So why did he decide to refer to the water temperature in degrees Celsius? In my experience, “Is the water cold?” has always been a yes/no question with the option of a little elaboration if the mood permits.

Could it be an homage to Anders Celsius, the founder of the measurement, and one of Sweden's favourite sons?

But referring to water temperatures is just the tip of the iceberg. Allow me to provide a few more examples of Swedes and their fixation with numbers before we try and figure out why they do it.

Swedes describe houses in numbers, in square metres to be precise. It would be nothing strange to hear a Swede say “I got a new apartment, a 56 on Södermalm” (except for the fact that finding any accommodation in Stockholm is a small miracle in itself).

Swedish people often are extremely precise when giving directions, too. I've lost count (!) of the times I've heard an insanely detailed figure from a helpful Swede. “Turn left in 1,300 metres” or “I saw you yesterday, you were 1.5 metres in front of me”. Both of these I've heard recently.

And let’s not forget the Holy Grail of numbers in Sweden – the personal number (personnummer) – which gives Swedes and foreigners alike a unique identity. This ten digit number is the password to a smooth life in Sweden. I don't think I'll ever forget when I'd first arrived here and my girlfriend checked into the dentist by typing her magic number into a machine, and her name was mysteriously called ten minutes later.

But these aren't the most amazing of the mathematical mannerisms. My favourite Swedish habit is how they use week numbers. Yes, in Sweden, they actually refer to the weeks using digits. And regularly. I recently walked into a restaurant and asked if it was too late in the day for brunch and was confused by the answer.

“Brunch is off the menu until week 33,” the waitress responded.

Week 33? I didn't even know at the time what week we were in, let alone when I could expect my brunch. Swedes specifically use week numbers for planning (“I'm heading to Spain in week 34”) but are always aware of the week number they’re in.

In an attempt to prove this, on Friday (or – if you're a Swede – in week 32), I tested Stockholmers to see if they could tell me what week number we were in. See for yourself (below).

So now that we know how they love their numbers, let's think about why. This is the real question, and I've got three theories, ordered numerically for any Swedes still reading.

1. Imagination

If you were to ask French author Antoine de Saint-Exupéry, he might have said that the Swedes, like the grown-ups in The Little Prince, are using numbers due to a lack of imagination.

“Grown-ups love numbers,” he wrote. “If you tell grown-ups, 'I saw a beautiful red brick house, with geraniums at the windows and doves on the roof…,' they won’t be able to imagine such a house. You have to tell them, 'I saw a house worth a hundred francs.' Then they exclaim, 'What a pretty house!'”

A 56 on Södermalm probably sounds very attractive indeed.

2. The need to be correct

If you use a number rather than a description, you can be exactly right. If the water is 22C, the bather will know exactly what they're in for. You can't leap out of the water and say “But you said it was 22!”

3. Efficiency

Using numbers rules out confusion. There are more than 9 million unique personal numbers in Sweden. There are also over 250,000 people with the surname Andersson. Introducing yourself as Johan Andersson at the Tax Office would cause hysteria. Referring to people by number makes sense, right? You do the maths.

Personally, I think it's an efficiency thing. The Swedes may sound like robots sometimes, but they are an efficient bunch. And while it may cut short the odd conversation, when you get used to it, you'll always know what you're in for before diving in the water.

Oh, and for the record, a lake at 22 is not cold at all – it's quite refreshing. And I'm never going to refer to it by number.

Oliver Gee

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