Zero: The Biography of a Dangerous Idea by Charles Seife

A book group of mine read Zero once, at the suggestion of a member who was into microhistories. Boy, did everyone hate it but me, because it has math in it. However, Zero don't require you to be good at math, just to like it (and history). And you can skip the mathy parts if you want.

After I read the book I liked to buttonhole my friends and family and tell them the things I read about in Zero. For example, our counting system is based on groups of 10s - that's probably because after you count to ten on your fingers, you start over. Somebody who lived in what is now France must have counted in groups of twenty, since quatre-vingts, 80, is literally "four twenties". And our time system is based on units of 60, because the Babylonians did that for astronomical reasons.

Anyway, getting back to the main character of the book, zero didn't exist for a long time because you didn't need it to count. Instead zero developed as a placeholder, because people got tired of making 10 hash marks instead of writing "10".

And that's where things get "dangerous". The ancient Greeks didn't like to use zero, because its existence implies both the infinite and the void, "two ideas that were poisonous to Western doctrine" (page 39) or Greek philosophy at least. (Infinity is what you get when you divide numbers by zero).

If you know any math-and-history lovers out there, please check this book out for them.