## the idea of a fully operational zero...

"Michel de Montaigne, whose essays transformed Western consciousness and literature, was not capable of solving basic arithmetic problems. And most other people would not be able to do so either, if not for the invention of decimal notation by an unknown mathematician in India 1500 years ago." The Greatest Mathematical Discovery? (expanded pdf) a paper written for the US Dept. of Energy makes this assertion based in part on the work of Georges Ifrah. [via]
posted by jessamyn on Aug 26, 2010 - 44 comments

## LibraryVenture!

Mazes and Monsters? Dungeons and Dragons? Faugh! When the Earth's very history is at stake, it's time for Tomes and Talismans! Learn the Dewey Decimal System and other library skills with Ms. Bookhart, a librarian cryogenically preserved from the 1980's and revived by The Users to save the books of Future Earth from technology-destroying race of alien beings, The Wipers. 260 of the geekiest minutes ever committed to video.
posted by Ambrosia Voyeur on Jul 25, 2008 - 15 comments

## .99999...=1

No, I'm sorry, it does. There are some arguments that never end. John or Paul? "Another thing coming" or "Another think coming?" But none has the staying power of "Is 0.999999...., with the 9s repeating forever, equal to 1?" A high school math teacher takes on all doubters. Round 2. Round 3. Refutations of some popular "They're not equal" arguments. Refutations, round 2. You don't have to a mathematician to get in on the fun: .99999=1 discussed on a conspiracy theory website, an Ayn Rand website (where it is accused to violating the "law of identity"), and a World of Warcraft forum. But never, as far as I can tell, on MetaFilter.
posted by escabeche on Sep 30, 2007 - 256 comments

## 3 is an odd prime, 5 is an odd prime, 7 is an odd prime, 9 is a very odd prime...

The Prime Game is not really much of a game, but it is a neat & little-known fact about the decimal representation of prime numbers.
posted by Wolfdog on Jul 10, 2007 - 24 comments

Page: 1