March 30, 2026
Roman vs Arabic: 200‑year beef
Fibonacci's Composed Fractions
Medieval math meets modern code; commenters cry change takes centuries
TLDR: A fresh look at Fibonacci’s fraction style maps medieval math to modern steps and code. Commenters fixated on how replacing Roman numerals took 200 years, spinning jokes and warnings about slow adoption—proof that even better tools need time, trust, and people ready to switch.
Fibonacci just got the internet treatment: a deep-dive revives his medieval composed fractions—a way to write mixed units before decimals—complete with step‑by‑step recipes and even modern code to do the math. That’s neat, but the comments stole the show. One reader dropped an interactive visualiser and the thread turned into a playground for breaking numbers into elegant slices.
The spiciest take? A reminder that switching from Roman numerals to today’s digits took roughly two centuries. Cue the chorus: change is hard, gatekeepers are real, and your office’s painful software migration suddenly feels historic. Some cheered the piece for showing that “new tech” once meant better bookkeeping, not just shinier apps. Others side‑eyed the TypeScript nod with “please, not code in my history,” while math nerds happily bridged eras, arguing old notation was basically the UX of its day. Jokes flew about accountants clinging to Roman numerals like they’re legacy spreadsheet macros, and memes compared Fibonacci’s hustle to modern feature rollouts: slow, controversial, inevitable. Verdict from the crowd: the math is cool, the history cooler, and the real lesson is timeless—tools change only when people do, and that clock moves painfully slow. Also: that visualiser link became everyone’s new toy today.
Key Points
- •Fibonacci’s Liber Abaci advocated Hindu-Arabic numerals and included a composed (linked) fractions notation for mixed‑radix quantities.
- •The article derives algorithms for arithmetic with composed fractions from Fibonacci’s examples and presents them as recipes and in TypeScript.
- •Liber Abaci’s fifteen chapters span numerals, integer arithmetic, fractions, business problems, algebraic methods, roots, and geometry.
- •Fibonacci’s education included exposure to Hindu-Arabic numerals, Arabic mathematics, and Euclid’s algorithm during travels to Bugia (Béjaïa, Algeria).
- •Historians differ on Liber Abaci’s precedence and impact, but among extant works it is noted for comprehensiveness and fewer errors; the composed fractions notation has Arabic precedents.