"A person should not go to sleep at night until the debits equal the credits"

Luca Pacioli: The Father of Accounting

In 1494, the first book on double-entry accounting was published. The author was an Italian friar, Luca Pacioli. His impact on accounting was so great that five centuries later, accountants from around the world gathered in the Italian village of San Sepulcro to celebrate the anniversary of the book's publication.The first accounting book actually was one of five sections in Pacioli's mathematics book titled "Everything about Arithmetic, Geometry, and Proportions." This section on accounting served as the world's only accounting textbook until well into the 16th century.

Since Pacioli was a Franciscan friar, he might be referred to simply as Friar Luca. While Friar Luca is often called the "Father of Accounting," he did not invent the system. Instead, he simply described a method used by merchants in Venice during the Italian Renaissance period. His system included most of the accounting cycle as we know it today. For example, he described the use journals and ledgers, and he warned that a person should not go to sleep at night until the debits equalled the credits! His ledger included assets (including receivables and inventories), liabilities, capital, income, and expense accounts. Friar Luca demonstrated year-end closing entries and proposed that a trial balance be used to prove a balanced ledger. Also, his treatise alludes to a wide range of topics from accounting ethics to cost accounting.

Pacioli was about 49 years old in 1494 - just two years after Columbus discovered America - when he returned to Venice for the publication of his fifth book, Summa de Arithmetica, Geometria, Proportioni et Proportionalita (Everything About Arithmetic, Geometry and Proportion). It was written as a digest and guide to existing mathematical knowledge, and bookkeeping was only one of five topics covered. The Summa's 36 short chapters on bookkeeping, entitled De Computis et Scripturis (Of Reckonings and Writings) were added "in order that the subjects of the most gracious Duke of Urbino may have complete instructions in the conduct of business," and to "give the trader without delay information as to his assets and liabilities" (All quotes from the translation by J.B. Geijsbeek, Ancient Double Entry Bookkeeping: Lucas Pacioli's Treatise, 1914).

Numerous tiny details of bookkeeping technique set forth by Pacioli were followed in texts and the profession for at least the next four centuries, as accounting historian Henry Rand Hatfield put it, "persisting like buttons on our coat sleeves, long after their significance had disappeared." Perhaps the best proof that Pacioli's work was considered potentially significant even at the time of publication was the very fact that it was printed on November 10, 1494. Guttenberg had just a quarter-century earlier invented metal type, and it was still an extremely expensive proposition to print a book.[...]

Follow the link above for references. I'm just about to complete an online course about using the Double-entry bookkeeping system, and I think the system is brilliant. So I found this history interesting. More historical facts from Wikipedia:

[...] The earliest extant accounting records that follow the modern double-entry form are those of Amatino Manucci, a Florentine merchant at the end of the 13th century.[1] Another old extant evidence of full double-entry bookkeeping is the Farolfi ledger of 1299-1300. Giovanino Farolfi & Company were a firm of Florentine merchants whose head office was in Nîmes who also acted as moneylenders to the Archbishop of Arles, their most important customer.[2] Some sources suggest that Giovanni di Bicci de' Medici introduced this method for the Medici bank in the 14th century.

However, the oldest discovered record of a complete double-entry system is the Messari (Italian: Treasurer's) accounts of the Republic of Genoa in 1340. The Messari accounts contain debits and credits journalised in a bilateral form, and contains balances carried forward from the preceding year, and therefore enjoy general recognition as a double-entry system.[3] By the end of the 15th century, the bankers and merchants of Florence, Genoa, Venice and Lübeck used this system widely.

Luca Pacioli, a Franciscan friar and collaborator of Leonardo da Vinci, first codified the system in his mathematics textbook Summa de arithmetica, geometria, proportioni et proportionalità published in Venice in 1494.[4] Pacioli is often called the "father of accounting" because he was the first to publish a detailed description of the double-entry system, thus enabling others to study and use it.[5][6] There is however controversy among scholars lately that Benedetto Cotrugli wrote the first manual on a double-entry bookkeeping system in his 1458 treatise Della mercatura e del mercante perfetto.[7][8][9][9][1 [...]

So perhaps it was the Florentine Merchants who invented the system? Well whoever it was, I'm a fan!

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