# The increased flexibility of Hindu-Arabic numerals

From Against the Gods: The Remarkable Story of Risk
Despite Emperor Frederick's patronage of Fibonacci's book and the book's widespread distribution throughout Europe, introduction of the Hindu-Arabic numbering system provoked intense and bitter resistance up to the early 1500s. Here, for once, we can explain the delay. Two factors were at work.

Part of the resistance stemmed from the inertial forces that opposed any change in matters hallowed by centuries of use. Learning radically new methods never finds an easy welcome.

The seocnd factor was based on more solid ground: it was easier to commit fraud with the new numbers than with the old. Turning a 0 into a 6 or a 9 was temptingly easy, and a 1 could be readily converted into a 4, 6, 7, or 9 (one reason Europeans write 7 as [a 7 with a line through it, don't know the HTML code -- EKR]). Although the new numbers had gained their first foothold in Italy, where education levels were high, Florence issued an edict in 1229 that forbade bankers from using the "infidel" symbols. As a result, many people who wanted to learn the new system had to disguise themselves as Moslems in order to do so.

The invention of printing with movable type in the middle of the fifteenth century was the catalyst that finally overcame opposition to the full use of the new numbers. Now the fraudulent alterations were no longer possible. Now the ridiculous complications of using Roman numerals became clear to everyone.

Of course, the invention of computer-based accounting made it (once again) easy to make fraudulent alterations, but by then we'd developed mathematical techniques that made it impossible to commit accounting fraud.

There is no unicode character for seven-with-a-line-through-it as distinct from seven with no line. It's merely a font glyphing thing. There are a couple dozen seven-related unicode glyphs, but none of them are "european seven".

No wonder I couldn't find it!