Once upon a time, Luca Pacioli wrote a math book. It was just a little survey and should have been treated like ordinary books of the time and read and then disappeared into historical archives and forgotten. A few brief chapters on practical mathematics made this one special.
The time was 1494. Columbus had discovered America just two years before. The author was a Franciscan monk.
The chapter on practical mathematics addressed mathematics in business. He said that the successful merchant needs three things: sufficient cash or credit, an accounting system that can tell him how he’s doing, and good bookkeeper to operate it. His accounting system consisted of journals and ledgers. It rested on the invention of double-entry bookkeeping. Debits were on the left side because that’s what “debit” meant, “the left”. The numbers on the right were named “credits”.
If everything was done right, then the bookkeeper could do a trial balance (“summa summarium”). Add up all the debits and then add up all the credits, he said. If everything had been done right, the totals should match. If not, “that would indicate a mistake in your Ledger, which mistake you will have to look for diligently with the industry and intelligence God gave you.” He wrote.
Experience
Before computers came along Jack had never got a trial balance right the first time. Many hours were spent looking for the mistakes, though not necessarily with the reverent attitude that Father Pacioli advised!
Double-entry bookkeeping was so simple and met the needs of business so well that it caught on immediately.
In 1850 14 accountants offered services to the public in New York City, 4 in Philadelphia, and 1 in Chicago. The British Isles was the superpower of world commerc ...