- Choose a script above, or Mixed for several at once. Eight questions a round.
- Tap the answer cards. In the first two questions, tap a digit to flip it and see its value.
- Match pairs: tap a number, then its twin. A round with no slips scores a point.
- In Chinese, build numbers from character tiles: 三百四十五 is 3 × 100 + 4 × 10 + 5, or 345. The ⌫ tile takes back the last one.
- The Digit chart tab shows the digits of the script you are playing.
Where the digits come from
Our digits most likely came from India. Writers in the Middle Ages called them Indian, and Arab writers knew them as Indian from the early 800s. In 1202 Leonard of Pisa, called Fibonacci, wrote a book on them and called them the nine Indian figures. The forms that reached Italy through Spain looked much more like ours than the forms used in the eastern Arab lands did. Thai and Malayalam digits are of the same general kind as the Indian ones.
The digit shapes are the Unicode characters. The history follows David Eugene Smith and Louis Charles Karpinski, The Hindu-Arabic Numerals (1911), and Smith, History of Mathematics (1925). The menus are the ones in Menu Order.
Same Number, Many Scripts
The digits most of the world writes today came from India. Arab writers knew them as Indian figures from the early 800s, and in 1202 Leonard of Pisa, called Fibonacci, wrote a book that taught them in Europe. On the way the shapes drifted: the forms that reached Italy through Spain look like ours, while the eastern Arab forms became the digits of Arabic today. Devanagari, Bengali and Thai digits are cousins from the same family. Chinese works differently, building numbers from words: three hundred four ten five.
In Hearth Library
- Living Scripts, a collection: Learning to read the world's writing systems
- Keeping Time, a collection: How people named the months and days, fixed the year and kept a diary
Part of Ancient Numbers. An early version: the game’s content is a first draft, not yet checked by a second reader.