De Thiende

De Thiende, published in 1585 in the Dutch language by Simon Stevin, is remembered for extending positional notation to the use of decimals to represent fractions.

Stevin also produced a French language version, and according to Sarton, "As the Flemish and French texts were both written by the author, edited by him, and published at almost the same time in the same printing shop, they have practically the same standing as original sources of STEVIN’s thought.

"[1]: 162 The Princeton Companion to Mathematics provides the following estimation of Stevin's contribution to positional notation:[2] The importance of Stevin's book De Thiende was expressed in The Princeton Companion to Mathematics:[2] The idea of extending the decimal place-value system to include fractions was discovered by several mathematicians.

The most influential of these was Simon Stevin, a Flemish mathematician and engineer who popularized the system in a booklet called De Thiende ("The tenth"), first published in 1585.

The cover page, in fact, announces that the book is for astrologers, surveyors, measurers of tapestries.On the dedication, Sarton wrote, "The dedication 'To astrologers, landmeasurers, measurers of tapestry and wine casks, and steriometricians in general, mint-masters and merchants all, SIMON STEVIN, greetings' has such a queer ring that I wonder whether the author did not make it with his tongue in his cheek.