How Does The Four Color Map Theorem - Numberphile Work?

The Four Color Map Theorem says that you only need four colors to color any map so no two touching areas have the same color.

Imagine you're playing with a coloring book, not just any coloring book, but one where every page is a map of different countries. You want to color each country, and if two countries share a border (like a line), they can’t be the same color. But here's the fun part: no matter how complicated or twisted that map looks, you’ll never need more than four colors.

Like Coloring with Friends

Think of it like coloring with your friends. Each friend picks a color and colors their country. If two countries are next to each other, they can’t pick the same color, but there’s always another color ready for them. And even if the map is super messy or has lots of little islands, you’ll still only need four different colors in total.

The Secret Behind It All

Mathematicians spent a long time trying to prove this, and finally did! They showed that no matter how weird your map is, four colors are enough. It’s like having a small box with just four crayons, and you know it’ll always be enough for any map you try to color.

Take the quiz →

Examples

  1. A child colors a map with four crayons, making sure no two neighboring countries have the same color.
  2. A simple drawing of continents on paper shows how just four colors can prevent matching colors next to each other.
  3. A teacher uses colored pencils to show that any map needs only up to four different colors.

Ask a question

See also

Discussion

Recent activity