联合国投票换掉世界地图：因为这张地图，把非洲画小了四百五十年

Let's start with a number: fourteen.

Africa's area is fourteen times that of Greenland.

But on the world map you have looked at since childhood, the two look about the same size.

On September the fourth, the UN General Assembly voted to replace that map.

A hundred and sixty-four in favour, one against, six abstentions.

This sounds like a small thing. It is not.

Let's get the problem straight first.

The earth is a sphere; a map is a flat surface.

Flatten a sphere and you are always stretching something.

This is not a matter of technology being insufficient — it is mathematically impossible.

So there is no completely correct map of the world anywhere.

Every map lies somewhere.

The question is where it chooses to lie.

The one most common in schools is called the Mercator projection.

It was made by a sixteenth-century Flemish cartographer, more than four hundred and fifty years ago.

His purpose was completely explicit: it was for navigation.

On this map, you draw a straight line at a fixed angle and a ship can simply follow it.

That property mattered enormously to sailors, so it stayed in use for centuries.

The cost is this: the closer you get to the poles, the more area gets inflated.

Greenland is blown up into something monstrous.

Africa straddles the equator, right in the stretch that gets compressed.

And so a fourteen-fold difference disappears from the picture.

The problem is where the map is hung.

It hangs on the wall of a primary school classroom.

It appears in textbooks, in the news, in weather forecasts, in the default view of the map on your phone.

A child looks at a map that draws Africa small, from age six to age sixteen.

Nobody ever tells them it is distorted.

They simply, slowly, form an intuition: Africa is roughly that big.

That intuition follows them for life, and shapes how important they judge that continent to be.

This is exactly what the people backing the change are talking about: it is a question of perception.

The proposal came from African Union member states together with the Bahamas, with Togo pushing it forward.

The alternative they recommend is the Equal Earth projection, made in 2018 by three cartographers.

What it does is preserve true relative area, at the cost of distorting shape a little.

In other words, it lies too — it has just moved the lie onto shape.

For a classroom, that is a good trade.

A student needs to know which landmass is bigger; they do not need the exact angle of a coastline.

Two things have to be said clearly, or this would not be fair.

First, the resolution has no legal force.

It merely asks schools, governments, international bodies and technology companies to switch to equal-area maps.

Nobody is compelled.

Second, the resolution states plainly that navigation at sea and in the air continues to use Mercator, for which it remains entirely suitable.

So the real issue is this: Mercator was being used somewhere it was never meant to be.

Think about it: that map on your classroom wall, which you looked at for years.

Did you ever once doubt it?