How did zero reach Europe?

That time, that place

He was a Pisan merchant's son. When his father took a trading post in the North African port of Bejaia, the boy grew up there and learned the calculating methods the Arab merchants used.

Why this question

Europe then used Roman numerals. Addition can be managed; multiplication and division essentially cannot.

So calculation was the work of specialists with counting boards. The trouble is that once you move the beads, the process is gone. When the answer is wrong there is no way to trace where it went wrong.

What was found

The numerals that came from India through the Arab world give each place its own value, and include zero. So you can multiply in aligned columns on paper, and the working stays on the page — meaning an error can be found and corrected.

In the Liber Abaci, Fibonacci introduced the system and filled it with real commercial problems: currency exchange, interest, dividing profit among partners, ratios in alloys. The multiplying rabbits were one exercise among many.

Merchants took it up first. Governments and universities held out for a long time. In 1299 Florence forbade the numerals in bank ledgers, on the grounds that a stroke could be added to alter them.

Terms on this card

Place-value notation