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Simon Stevin (1548/49 – 1620) was a Flemish mathematician and engineer. He was active in a great many areas of science and engineering, both theoretical and practical. He also translated various mathematical terms into Dutch, making it one of the few European languages in which the word for mathematics, wiskunde ("the art of what is certain"), was not derived from Greek (via Latin).

Biography

Stevin was born in Bruges, Flanders (now Belgium) in the year 1548, to Antheunis Stevin and Cathelyne van der Poort. Very little has been recorded about his life. Even the exact date of birth and the date and place of his death (The Hague or Leiden) are uncertain. It is known that he left a widow with two children; and one or two hints scattered throughout his works inform us that he began life as a merchant's clerk in Antwerp, that he travelled in Poland, Denmark and other parts of northern Europe. After his travels, he became advisor and tutor of Prince Maurice of Nassau, who asked his advice on many occasions, and made him a public officer — at first director of the so-called "waterstaet" (the government authority for public works), and later quartermaster-general.

In Bruges there is a Simon Stevin Square which contains his statue by Eugen Simonis, which includes his inclined plane diagram.

Statue of Stevin (detail)

Statue(detail):Inclined plane diagram

Discoveries and inventions

His claims to fame are varied. His contemporaries were most struck by his invention of a so-called land yacht, a carriage with sails, of which a little model had been preserved in Scheveningen until 1802. The carriage itself had been lost long before. Around the year 1600 Stevin, with Prince Maurice of Orange and twenty-six others, made use of it on the beach between Scheveningen and Petten. The carriage was propelled solely by the force of wind, and acquired a speed which exceeded that of horses.

Philosophy of science

Stevin developed a theory about a bygone age of wisdom, for which even Hugo Grotius gave him great credit. Stevin's goal was to bring about a second age of wisdom, in which mankind would have recovered all of its earlier knowledge. He had deduced that the language spoken in this age would have had to be Dutch, because, as he had showed empirically, in that language, more concepts could be indicated with monosyllabic words than in any of the (European) languages he had compared it with. This was one of the reasons why he wrote all of his works in Dutch and left translations to others. The other reason was that he wanted his works to be practically useful to people who had not mastered the common scientific language of the time, Latin.

Geometry and physics
Stevin's proof of the law of the equilibrium on an inclined plane

Stevin was the first to show how to model regular and semiregular polyhedra by delineating their frames in a plane. He also distinguished stable from unstable equilibria.

Stevin proved the law of the equilibrium on an inclined plane, using an ingenious and intuitive diagram showing a rope containing evenly spaced beads draped over an inclined plane (see the illustration on the side). Physicist Richard Feynman mentions with reverence in his Lectures on Physics that with the diagram, Stevin elegantly proves the law of conservation of energy. Feynman further imagines that the diagram is inscribed on Stevin's tombstone. In reality there is no such grave, although Stevin's statue in Bruges does bear the diagram.

He demonstrated the resolution of forces before Pierre Varignon, which had not been remarked previously, even though it is a simple consequence of the law of their composition.

Stevin discovered the hydrostatic paradox, which states that the downward pressure of a liquid is independent of the shape of the vessel, and depends only on its height and base.

He also gave the measure for the pressure on any given portion of the side of a vessel.

He was the first to explain the tides using the attraction of the moon.

In 1586, he demonstrated that two objects of different weight fall down with exactly the same acceleration.[1]

Music theory

Stevin was the first author in the West (1585, simultaneously with, and independently of, Zhu Zaiyu in China) to give a mathematically accurate specification for equal temperament. He appears to have been inspired by the writings of the Italian lutenist and musical theorist Vincenzo Galilei (father of Galileo Galilei), a onetime pupil of Gioseffo Zarlino.

Bookkeeping

Bookkeeping by double entry may have been known to Stevin, as he was a clerk in Antwerp in his younger years, either practically or through the medium of the works of Italian authors such as Luca Pacioli and Gerolamo Cardano. However, Stevin was the first to recommend the use of impersonal accounts in the national household. He brought it into practice for Prince Maurice, and recommended it to the French statesman Sully.

It was Stevin who persuaded merchants to make it a rule to summarize accounts at the end of every year in a chapter entitled Coopmansbouckhouding op de Italiaensche wyse (Dutch: "Commercial Book-keeping in the Italian Way") of his Wisconstighe ghedachtenissen (Dutch: "Mathematical memoirs", Leiden, 1605-08). Although the balance sheet he required every enterprise to prepare every year was based on entries of the ledger, it was prepared separately from the major books of account.[2]

Decimal fractions

Stevin wrote a 36-page booklet called De Thiende ('the art of tenths'), first published in Dutch in 1585 and translated into French as Disme. The full title of the English translation was Decimal arithmetic: Teaching how to perform all computations whatsoever by whole numbers without fractions, by the four principles of common arithmetic: namely, addition, subtraction, multiplication, and division. The concepts referred to in the booklet included unit fractions and Egyptian fractions.

Decimal fractions had been employed for the extraction of square roots centuries before his time by Islamic mathematicians such as Al-Kashi[3][4] but nobody established their daily use before Stevin. He felt that this innovation was so significant, that he declared the universal introduction of decimal coinage, measures and weights to be merely a question of time.

His notation is rather unwieldy. The point separating the integers from the decimal fractions seems to be the invention of Bartholomaeus Pitiscus, in whose trigonometrical tables (1612) it occurs and it was accepted by John Napier in his logarithmic papers (1614 and 1619).
Stevin-decimal notation.png

Stevin printed little circles around the exponents of the different powers of one-tenth. That Stevin intended these encircled numerals to denote mere exponents is clear from the fact that he employed the very same symbol for powers of algebraic quantities. He didn't avoid fractional exponents; only negative exponents don't appear in his work.

Stevin wrote on other scientific subjects—for instance optics, geography, astronomy—and a number of his writings were translated into Latin by W. Snellius (Willebrord Snell). There are two complete editions in French of his works, both printed in Leiden, one in 1608, the other in 1634.

According to van der Waerden (1985, p. 69), Stevin's "general notion of a real number was accepted, tacitly or explicitly, by all later scientists".

Neologisms

Stevin thought the Dutch language to be excellent for scientific writing, and he translated many of the mathematical terms to Dutch. As a result, Dutch is one of the few Western European languages that have a lot of mathematical terms that do not stem from Latin. This includes the very name Wiskunde (Mathematics).

His eye for the importance of having the scientific language be the same as the language of the craftsmen may show from the dedication of his book De Thiende ('The Disme' or 'The Tenth'): 'Simon Stevin wishes the stargazers, surveyors, carpet measurers, body measurers in general, coin measurers and tradespeople good luck.' Further on in the same pamphlet, he writes: "[this text] teaches us all calculations that are needed by the people without using fractions. One can reduce all operations to adding, subtracting, multiplying and dividing with integers."

Some of the words he invented evolved: 'aftrekken' (subtract) and 'delen' (divide) stayed the same, but over time 'menigvuldigen' became 'vermenigvuldigen' (multiply, the added 'ver' has no meaning). 'Vergaderen' became 'optellen' (add).

Another example is the Dutch word for diameter: 'middellijn', lit.: line through the middle.

The word 'zomenigmaal' (quotient lit. 'that many times') has become the perhaps less poetic 'quotiënt' in modern day Dutch.

Other terms did not make it into modern day mathematical Dutch, like 'teerling' (die, although still being used in the meaning as die), instead of cube. His books were bestsellers.

Publications

Amongst others, he published:

* Tafelen van Interest (Tables of interest) in 1582;
* Problemata geometrica in 1583;
* De Thiende (La Theinde, The tenth) in 1585 in which decimals were introduced in Europe;
* La pratique d'arithmétique in 1585;
* L'arithmétique in 1585 in which he presented a uniform treatment for solving algebraic equations;
* De Beghinselen der Weeghconst in 1586, accompanied by De Weeghdaet;
* De Beghinselen des Waterwichts (Principles on the weight of water) in 1586 on the subject of hydrostatics;
* Vita Politica. Named Burgherlick leven (Civil life) in 1590;
* De Stercktenbouwing (The construction of fortifications) published in 1594;
* De Havenvinding (Position finding) published in 1599;
* De Hemelloop in 1608 in which he voiced support for the Copernican theory.
* Wiskonstighe Ghedachtenissen (Mathematical Memoirs, Latin: Hypomnemata Mathematica). This included earlier works like De Driehouckhandel (Trigonometry), De Meetdaet (Practice of measuring), and De Deursichtighe (Perspective);
* Castrametatio, dat is legermeting and Nieuwe Maniere van Stercktebou door Spilsluysen (New ways of building of sluices) published in 1617;
* De Spiegheling der Singconst (Theory of the art of singing).

Trivia

The study association of mechanical engineering at the Technische Universiteit Eindhoven, W.S.V. Simon Stevin is named after Simon Stevin. In Stevin's memory, the association has called its bar "De Weeghconst" and owns a self-built fleet of land yachts.

Stevin, cited as Stevinus, is one of the favorite authors, if not the favorite author, of Uncle Toby Shandy in Laurence Sterne's The Life and Opinions of Tristram Shandy Gentleman.

External links

* O'Connor, John J.; Robertson, Edmund F., "Simon Stevin", MacTutor History of Mathematics archive, University of St Andrews, http://www-history.mcs.st-andrews.ac.uk/Biographies/Stevin.html .
* "Simon Stevin". Catholic Encyclopedia. New York: Robert Appleton Company. 1913. http://en.wikisource.org/wiki/Catholic_Encyclopedia_(1913)/Simon_Stevin.
* [2] contains an HTML version (including hyperlinks to explanations) of De Thiende and its translations into English, French and Swedish, and scans of these books
* [3] contains a lot more information about Simon Stevin
* [4] is the text of the Catholic Encyclopedia about Stevin. The author can hardly conceal his admiration, and for the rest the article is mostly a bibliography of Stevin's work.
* [5] is a short essay on Simon Stevin by S. Abbas Raza at 3 Quarks Daily
* [6] is an Internet bibliography regarding Simon Stevin.
* [7] treats Stevin's use of the rule of false position.
* http://www.newadvent.org/cathen/14293b.htm
* MathPages - Wonder En Is Gheen Wonder
* http://www.knaw.nl/publicaties/pdf/961083.pdf link to unpublished treatise of Simon Stevin on architecture, town planning and civil engineering - C. van den Heuvel. De Huysbou.

References

1. ^ Galileo Galilei: The Falling Bodies Experiment
2. ^ Takatera, Sadao: Early experiences of the British balance sheet, Kyoto Universtity Economic Review, Vol. 83, October 1962, p.37-38 [1]
3. ^ St Andrews School of Mathematics
4. ^ Flegg, Graham (2002). Numbers: Their History and Meaning. Dover Publications. p. 76. ISBN 0486421651, 9780486421650.

* Wikisource-logo.svg "Stevinus, Simon". Encyclopædia Britannica (11th ed.). 1911.