1.
Adolph Quetelet
–
Lambert Adolphe Jacques Quetelet ForMemRS was a Belgian astronomer, mathematician, statistician and sociologist. He founded and directed the Brussels Observatory and was influential in introducing statistical methods to the social sciences and his name is sometimes spelled with an accent as Quételet. He developed the body mass index scale, Adolphe was born in Ghent, the son of François-Augustin-Jacques-Henri Quetelet, a Frenchman and Anne Françoise Vandervelde, a Flemish woman. His father, François, was born at Ham, Picardy, in that capacity, he traveled with his employer on the Continent, particularly spending time in Italy. At about 31, he settled in Ghent and was employed by the city, francois died when Adolphe was only seven years old. Adolphe studied at the Ghent lycée, where he started teaching mathematics in 1815 at the age of 19, in 1819 he moved to the Athenaeum in Brussels and in the same year he completed his dissertation. Quetelet received a doctorate in mathematics in 1819 from the University of Ghent, shortly thereafter, the young man set out to convince government officials and private donors to build an astronomical observatory in Brussels, he succeeded in 1828. He became a member of the Royal Academy in 1820 and he lectured at the museum for sciences and letters and at the Belgian Military School. In 1825 he became correspondent of the Royal Institute of the Netherlands, from 1841 to 1851 he was supernumerair associate in the Institute, and when it became Royal Netherlands Academy of Arts and Sciences he became foreign member. In 1850, he was elected a member of the Royal Swedish Academy of Sciences. Quetelet also founded several statistical journals and societies, and was interested in creating international cooperation among statisticians. In 1855 Quetelet suffered from apoplexy, which diminished but did not end his scientific activity and he died in Brussels on 17 February 1874, and is buried in the Brussels Cemetery. His scientific research encompassed a range of different scientific disciplines, meteorology, astronomy, mathematics, statistics, demography, sociology, criminology. He made significant contributions to development, but he also wrote several monographs directed to the general public. Quetelet was a liberal and an anticlerical, but not an atheist or materialist nor a socialist, the new science of probability and statistics was mainly used in astronomy at the time, where it was essential to account for measurement errors around means. This was done using the method of least squares, Quetelet was among the first to apply statistics to social science, planning what he called social physics. He was keenly aware of the complexity of social phenomena. His goal was to understand the statistical laws underlying such phenomena as crime rates and he wanted to explain the values of these variables by other social factors

Adolph Quetelet
–
Adolphe Quetelet

2.
Romanus Adrianus
–
Adriaan van Roomen, also known as Adrianus Romanus, was a Flemish mathematician. Van Roomen was born in Leuven, the son of Adriaan Van Roomen and he became a professor, and then travelled extensively in Europe. After studying at the Jesuit College in Cologne, Roomen studied medicine at Leuven, Roomen was professor of mathematics and medicine at Louvain from 1586 to 1592, he then went to Würzburg where again he was professor of medicine and became Mathematician to the Chapter. He met Kepler, and discussed with François Viète two questions about equations and tangencies and he then spent some time in Italy, particularly with Clavius in Rome in 1585. He was ordained a priest in 1604, after 1610 he tutored mathematics in Poland. He worked in algebra, trigonometry and geometry, and on the expansion of π. His publication of 1595, Parvum theatrum urbium, contained Latin verse on the cities of Italy and he solved the Problem of Apollonius using a new method that involved intersecting hyperbolas. The Adriaan van Roomen affair Zamojski Academy Ideae mathematicae pars prima, digital Parvvm Theatrvm Vrbivm siue Vrbivm Praecipvarvm Totivs Orbis Brevis & methodica Descriptio. Digital OConnor, John J. Robertson, Edmund F. Adriaan van Roomen, MacTutor History of Mathematics archive, media related to Adriaan van Roomen at Wikimedia Commons

Romanus Adrianus
–
Adriaan van Roomen

3.
Adriaen Anthonisz
–
Adriaan Anthonisz was a Dutch mathematician, surveyor, cartographer, and military engineer who specialized in the design of fortifications. From 1582, he served as burgomaster of Alkmaar in the Netherlands. In 1585 Anthonisz discovered that the ratio of a circumference to its diameter, later called pi. His son Adriaan Metius later published his fathers results, and the value 355/113 is traditionally referred to as Metius number and he is regarded as one of the first military engineers to apply the principles of the Dutch fortification system. Some of his accomplishments included mapping the Berger lake and expanding and fortifying Naarden and Muiden. Adriaan fathered two sons, and named them both Metius and they each became prominent members of society. Adriaan Metius was a Dutch geometer and astronomer, jacob Metius worked as an instrument-maker and a specialist in grinding lenses and is often credited as the inventor of the telescope

Adriaen Anthonisz
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Statue of Adriaen Anthonisz by John Bier (nl)

4.
Arcamedies
–
Archimedes of Syracuse was a Greek mathematician, physicist, engineer, inventor, and astronomer. Although few details of his life are known, he is regarded as one of the scientists in classical antiquity. He was also one of the first to apply mathematics to physical phenomena, founding hydrostatics and statics and he is credited with designing innovative machines, such as his screw pump, compound pulleys, and defensive war machines to protect his native Syracuse from invasion. Archimedes died during the Siege of Syracuse when he was killed by a Roman soldier despite orders that he should not be harmed. Cicero describes visiting the tomb of Archimedes, which was surmounted by a sphere and a cylinder, unlike his inventions, the mathematical writings of Archimedes were little known in antiquity. Archimedes was born c.287 BC in the city of Syracuse, Sicily, at that time a self-governing colony in Magna Graecia. The date of birth is based on a statement by the Byzantine Greek historian John Tzetzes that Archimedes lived for 75 years, in The Sand Reckoner, Archimedes gives his fathers name as Phidias, an astronomer about whom nothing is known. Plutarch wrote in his Parallel Lives that Archimedes was related to King Hiero II, a biography of Archimedes was written by his friend Heracleides but this work has been lost, leaving the details of his life obscure. It is unknown, for instance, whether he married or had children. During his youth, Archimedes may have studied in Alexandria, Egypt and he referred to Conon of Samos as his friend, while two of his works have introductions addressed to Eratosthenes. Archimedes died c.212 BC during the Second Punic War, according to the popular account given by Plutarch, Archimedes was contemplating a mathematical diagram when the city was captured. A Roman soldier commanded him to come and meet General Marcellus but he declined, the soldier was enraged by this, and killed Archimedes with his sword. Plutarch also gives an account of the death of Archimedes which suggests that he may have been killed while attempting to surrender to a Roman soldier. According to this story, Archimedes was carrying mathematical instruments, and was killed because the thought that they were valuable items. General Marcellus was reportedly angered by the death of Archimedes, as he considered him a valuable asset and had ordered that he not be harmed. Marcellus called Archimedes a geometrical Briareus, the last words attributed to Archimedes are Do not disturb my circles, a reference to the circles in the mathematical drawing that he was supposedly studying when disturbed by the Roman soldier. This quote is given in Latin as Noli turbare circulos meos. The phrase is given in Katharevousa Greek as μὴ μου τοὺς κύκλους τάραττε

Arcamedies
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Archimedes Thoughtful by

Fetti (1620)

Arcamedies
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Cicero Discovering the Tomb of Archimedes by

Benjamin West (1805)

Arcamedies
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Artistic interpretation of Archimedes' mirror used to burn Roman ships. Painting by

Giulio Parigi.

Arcamedies
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A sphere has 2/3 the volume and surface area of its circumscribing cylinder including its bases. A

sphere and

cylinder were placed on the tomb of Archimedes at his request. (see also:

Equiareal map)

5.
C. Huyghens
–
Christiaan Huygens, FRS was a prominent Dutch mathematician and scientist. He is known particularly as an astronomer, physicist, probabilist and horologist, Huygens was a leading scientist of his time. His work included early telescopic studies of the rings of Saturn and the discovery of its moon Titan and he published major studies of mechanics and optics, and pioneered work on games of chance. Christiaan Huygens was born on 14 April 1629 in The Hague, into a rich and influential Dutch family, Christiaan was named after his paternal grandfather. His mother was Suzanna van Baerle and she died in 1637, shortly after the birth of Huygens sister. The couple had five children, Constantijn, Christiaan, Lodewijk, Philips, Constantijn Huygens was a diplomat and advisor to the House of Orange, and also a poet and musician. His friends included Galileo Galilei, Marin Mersenne and René Descartes, Huygens was educated at home until turning sixteen years old. He liked to play with miniatures of mills and other machines and his father gave him a liberal education, he studied languages and music, history and geography, mathematics, logic and rhetoric, but also dancing, fencing and horse riding. In 1644 Huygens had as his mathematical tutor Jan Jansz de Jonge Stampioen, Descartes was impressed by his skills in geometry. His father sent Huygens to study law and mathematics at the University of Leiden, Frans van Schooten was an academic at Leiden from 1646, and also a private tutor to Huygens and his elder brother, replacing Stampioen on the advice of Descartes. Van Schooten brought his mathematical education up to date, in introducing him to the work of Fermat on differential geometry. Constantijn Huygens was closely involved in the new College, which lasted only to 1669, Christiaan Huygens lived at the home of the jurist Johann Henryk Dauber, and had mathematics classes with the English lecturer John Pell. He completed his studies in August 1649 and he then had a stint as a diplomat on a mission with Henry, Duke of Nassau. It took him to Bentheim, then Flensburg and he took off for Denmark, visited Copenhagen and Helsingør, and hoped to cross the Øresund to visit Descartes in Stockholm. While his father Constantijn had wished his son Christiaan to be a diplomat, in political terms, the First Stadtholderless Period that began in 1650 meant that the House of Orange was not in power, removing Constantijns influence. Further, he realised that his son had no interest in such a career, Huygens generally wrote in French or Latin. While still a student at Leiden he began a correspondence with the intelligencer Mersenne. Mersenne wrote to Constantijn on his sons talent for mathematics, the letters show the early interests of Huygens in mathematics

C. Huyghens
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Christiaan Huygens by

Bernard Vaillant,

Museum Hofwijck,

Voorburg
C. Huyghens
–
Correspondance

C. Huyghens
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The

catenary in a manuscript of Huygens.

C. Huyghens
–
Christiaan Huygens, relief by

Jean-Jacques Clérion, around 1670?

6.
Bernoulli, Daniel
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Daniel Bernoulli FRS was a Swiss mathematician and physicist and was one of the many prominent mathematicians in the Bernoulli family. He is particularly remembered for his applications of mathematics to mechanics, especially fluid mechanics, Daniel Bernoulli was born in Groningen, in the Netherlands, into a family of distinguished mathematicians. The Bernoulli family came originally from Antwerp, at time in the Spanish Netherlands. After a brief period in Frankfurt the family moved to Basel, Daniel was the son of Johann Bernoulli, nephew of Jacob Bernoulli. He had two brothers, Niklaus and Johann II, Daniel Bernoulli was described by W. W. Rouse Ball as by far the ablest of the younger Bernoullis. He is said to have had a bad relationship with his father, Johann Bernoulli also plagiarized some key ideas from Daniels book Hydrodynamica in his own book Hydraulica which he backdated to before Hydrodynamica. Despite Daniels attempts at reconciliation, his father carried the grudge until his death, around schooling age, his father, Johann, encouraged him to study business, there being poor rewards awaiting a mathematician. However, Daniel refused, because he wanted to study mathematics and he later gave in to his fathers wish and studied business. His father then asked him to study in medicine, and Daniel agreed under the condition that his father would teach him mathematics privately, Daniel studied medicine at Basel, Heidelberg, and Strasbourg, and earned a PhD in anatomy and botany in 1721. He was a contemporary and close friend of Leonhard Euler and he went to St. Petersburg in 1724 as professor of mathematics, but was very unhappy there, and a temporary illness in 1733 gave him an excuse for leaving St. Petersberg. He returned to the University of Basel, where he held the chairs of medicine, metaphysics. In May,1750 he was elected a Fellow of the Royal Society and his earliest mathematical work was the Exercitationes, published in 1724 with the help of Goldbach. Two years later he pointed out for the first time the frequent desirability of resolving a compound motion into motions of translation and motion of rotation, together Bernoulli and Euler tried to discover more about the flow of fluids. In particular, they wanted to know about the relationship between the speed at which blood flows and its pressure, soon physicians all over Europe were measuring patients blood pressure by sticking point-ended glass tubes directly into their arteries. It was not until about 170 years later, in 1896 that an Italian doctor discovered a less painful method which is still in use today. However, Bernoullis method of measuring pressure is used today in modern aircraft to measure the speed of the air passing the plane. Taking his discoveries further, Daniel Bernoulli now returned to his work on Conservation of Energy. It was known that a moving body exchanges its kinetic energy for energy when it gains height

Bernoulli, Daniel
–
Daniel Bernoulli

7.
Dirk jan struik
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Dirk Jan Struik was a Dutch mathematician and Marxian theoretician who spent most of his life in the United States. Dirk Jan Struik was born in 1894 in Rotterdam, Netherlands, as a teachers son and it was in this school that he was first introduced to left-wing politics by some of his teachers. In 1912 Struik entered University of Leiden, where he showed great interest in mathematics and physics, influenced by the eminent professors Paul Ehrenfest and Hendrik Lorentz. In 1917 he worked as a high school teacher for a while. It was during this period that he developed his doctoral dissertation, in 1922 Struik obtained his doctorate in mathematics from University of Leiden. He was appointed to a position at University of Utrecht in 1923. The same year he married Ruth Ramler, a Czech mathematician with a doctorate from the Charles University of Prague, in 1924, funded by a Rockefeller fellowship, Struik traveled to Rome to collaborate with the Italian mathematician Tullio Levi-Civita. It was in Rome that Struik first developed a keen interest in the history of mathematics, in 1925, thanks to an extension of his fellowship, Struik went to Göttingen to work with Richard Courant compiling Felix Kleins lectures on the history of 19th-century mathematics. He also started researching Renaissance mathematics at this time, in 1926 Struik was offered positions both at the Moscow State University and the Massachusetts Institute of Technology. He decided to accept the latter, where he spent the rest of his academic career and he collaborated with Norbert Wiener on differential geometry, while continuing his research on the history of mathematics. He was made professor at MIT in 1940. Having joined the Communist Party of the Netherlands in 1919, he remained a Party member his entire life and it is therefore not surprising that Dirk suffered persecution during the McCarthyite era. He was accused of being a Soviet spy, a charge he vehemently denied, invoking the First and Fifth Amendments of the U. S. Constitution, he refused to answer any of the 200 questions put forward to him during the HUAC hearing. He was suspended from teaching for five years by MIT in the 1950s and he retired from MIT in 1960. Aside from purely academic work, Struik also helped found the Journal of Science and Society and he is the only one to mention Allvar Gullstrand. Struik died October 21,2000,21 days after celebrating his 106th birthday, D. J. Struik, editor, A source book in mathematics, 1200–1800. D. J. Struik, A concise history of mathematics, obituaries G. Alberts, and W. T. van Est, Dirk Jan Struik, Levensberichten en herdenkingen, pp. 107–114. Mathematician Professor Dirk Struik dies at 106, Dirk Jan Struiks Biography Dirk Jan Struik at the Mathematics Genealogy Project Works by or about Dirk Jan Struik in libraries

Dirk jan struik
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Dirk Jan Struik

8.
Franciscus van Schooten
–
Franciscus van Schooten was a Dutch mathematician who is most known for popularizing the analytic geometry of René Descartes. Van Schootens father was a professor of mathematics at the University of Leiden, having Christiaan Huygens, Johann van Waveren Hudde, Van Schooten met Descartes in 1632 and read his Géométrie while it was still unpublished. Finding it hard to understand, he went to France to study the works of important mathematicians of his time, such as François Viète. When Frans van Schooten returned to his home in Leiden in 1646, he inherited his fathers position and one of his most important pupils, Huygens. Over the next decade he enlisted the aid of other mathematicians of the time, de Beaune, Hudde, Heuraet, de Witt and this edition and its extensive commentaries was far more influential than the 1649 edition. It was this edition that Gottfried Leibniz and Isaac Newton knew, Van Schooten was one of the first to suggest, in exercises published in 1657, that these ideas be extended to three-dimensional space. Van Schootens efforts also made Leiden the centre of the community for a short period in the middle of the seventeenth century. Some Contemporaries of Descartes, Fermat, Pascal and Huygens, Van Schooten, robertson, Edmund F. Frans van Schooten, MacTutor History of Mathematics archive, University of St Andrews. An e-textbook developed from Frans van Schooten 1646 by dbook

Franciscus van Schooten
–
Frans van Schooten

Franciscus van Schooten
–
Exercitationum mathematicarum libri, 1656-1657

9.
J. Tits
–
Jacques Tits is a Belgium-born French mathematician who works on group theory and incidence geometry, and who introduced Tits buildings, the Tits alternative, and the Tits group. Tits was born in Uccle to Léon Tits, a professor, Jacques attended the Athénée of Uccle and the Free University of Brussels. His thesis advisor was Paul Libois, and Tits graduated with his doctorate in 1950 with the dissertation Généralisation des groupes projectifs basés sur la notion de transitivité. His academic career includes professorships at the Free University of Brussels, the University of Bonn and he changed his citizenship to French in 1974 in order to teach at the Collège de France, which at that point required French citizenship. Because Belgian nationality law did not allow dual nationality at the time and he has been a member of the French Academy of Sciences since then. Tits received the Wolf Prize in Mathematics in 1993, the Cantor Medal from the Deutsche Mathematiker-Vereinigung in 1996, and the German distinction Pour le Mérite. In 2008 he was awarded the Abel Prize, along with John Griggs Thompson, “for their profound achievements in algebra and he is a member of the Norwegian Academy of Science and Letters. He became a member of the Royal Netherlands Academy of Arts. He introduced the theory of buildings, which are structures on which groups act. The related theory of pairs is a tool in the theory of groups of Lie type. Of particular importance is his classification of all buildings of spherical type. In the rank-2 case spherical building are generalized n-gons, and in joint work with Richard Weiss he classified these when they admit a group of symmetries. In collaboration with François Bruhat he developed the theory of affine buildings, the Tits group and the Tits–Koecher construction are named after him. Buildings of spherical type and finite BN-pairs, lecture Notes in Mathematics, Vol.386. MR0470099 Tits, Jacques, Weiss, Richard M. Moufang polygons, MR1938841 J. Tits, Oeuvres - Collected Works,4 vol. J. Tits, Résumés des cours au Collège de France, Jacques Tits at the Mathematics Genealogy Project OConnor, John J. Robertson, Edmund F. Jacques Tits, MacTutor History of Mathematics archive, University of St Andrews. Biography at the Abel Prize site List of publications at the Université libre de Bruxelles

J. Tits
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Jacques Tits in May 2008

10.
Jean Bourgain
–
Jean, Baron Bourgain is a Belgian mathematician. He is currently an editor for the Annals of Mathematics, from 2012–2014, he was appointed a visiting scholar at UC Berkeley. Bourgain received his Ph. D. from the Vrije Universiteit Brussel in 1977 and he has been recognised by a number of awards, most notably the Fields Medal in 1994. In 2000 Bourgain connected the Kakeya problem to arithmetic combinatorics, in 2009 Bourgain was elected a foreign member of the Royal Swedish Academy of Sciences. In 2010, he received the Shaw Prize in Mathematics, in 2012, he and Terence Tao received the Crafoord Prize in Mathematics from the Royal Swedish Academy of Sciences. In 2016, he received the 2017 Breakthrough Prize in Mathematics, mathSciNet, Items authored by Bourgain, Jean. OConnor, John J. Robertson, Edmund F, Jean Bourgain, MacTutor History of Mathematics archive, University of St Andrews

Jean Bourgain
–
Jean Bourgain

11.
Johann Bernoulli
–
Johann Bernoulli was a Swiss mathematician and was one of the many prominent mathematicians in the Bernoulli family. He is known for his contributions to calculus and educating Leonhard Euler in the pupils youth. Johann was born in Basel, the son of Nicolaus Bernoulli, an apothecary, however, Johann Bernoulli did not enjoy medicine either and began studying mathematics on the side with his older brother Jacob. Throughout Johann Bernoulli’s education at Basel University the Bernoulli brothers worked together spending much of their time studying the newly discovered infinitesimal calculus and they were among the first mathematicians to not only study and understand calculus but to apply it to various problems. After graduating from Basel University Johann Bernoulli moved to teach differential equations, later, in 1694, he married Dorothea Falkner and soon after accepted a position as the professor of mathematics at the University of Groningen. At the request of Johann Bernoulli’s father-in-law, Johann Bernoulli began the voyage back to his town of Basel in 1705. Just after setting out on the journey he learned of his brother’s death to tuberculosis, Johann Bernoulli had planned on becoming the professor of Greek at Basel University upon returning but instead was able to take over as professor of mathematics, his older brother’s former position. As a student of Leibniz’s calculus, Johann Bernoulli sided with him in 1713 in the Newton–Leibniz debate over who deserved credit for the discovery of calculus, Johann Bernoulli defended Leibniz by showing that he had solved certain problems with his methods that Newton had failed to solve. Johann Bernoulli also promoted Descartes’ vortex theory over Newton’s theory of gravitation and this ultimately delayed acceptance of Newton’s theory in continental Europe. In consequence he was disqualified for the prize, which was won by Maclaurin, however, Bernoullis paper was subsequently accepted in 1726 when the Académie considered papers regarding elastic bodies, for which the prize was awarded to Pierre Mazière. Bernoulli received a mention in both competitions. Although Jacob and Johann worked together before Johann graduated from Basel University, shortly after this, Johann was jealous of Jacobs position and the two often attempted to outdo each other. After Jacobs death Johanns jealousy shifted toward his own talented son, in 1738 the father–son duo nearly simultaneously published separate works on hydrodynamics. Johann Bernoulli attempted to take precedence over his son by purposely predating his work two prior to his son’s. Johann married Dorothea Falkner, daughter of an Alderman of Basel and he was the father of Nicolaus II Bernoulli, Daniel Bernoulli and Johann II Bernoulli and uncle of Nicolaus I Bernoulli. The Bernoulli brothers often worked on the problems, but not without friction. In 1697 Jacob offered a reward for its solution, a protracted, bitter dispute then arose when Jacob challenged the solution and proposed his own. The dispute marked the origin of a new discipline, the calculus of variations, Bernoulli was hired by Guillaume de lHôpital for tutoring in mathematics

Johann Bernoulli
–
Johann Bernoulli (portrait by

Johann Rudolf Huber, circa 1740)

12.
Johan de Wit
–
As a republican he opposed the House of Orange. He was also strongly liberal, preferring lesser power to the central government, however, his negligence of the Dutch land army proved disastrous when the Dutch Republic suffered numerous early defeats in the Rampjaar. The rioters were never prosecuted, and historians have argued that William of Orange may have incited them, Johan de Witt was a member of the old Dutch patrician family De Witt. Johan and Cornelis both attended the Latin school in Dordrecht, which imbued both brothers with the values of the Roman Republic, after having attended the Latin school in Dordrecht, he studied at the University of Leiden, where he excelled at mathematics and law. He received his doctorate from the University of Angers in 1645 and he practiced law as an attorney in The Hague as an associate with the firm of Frans van Schooten. In 1650 he was appointed leader of the deputation of Dordrecht to the States of Holland, in December 1650, De Witt became the pensionary of Dordrecht. Once during the year 1652 in the city of Flushing, Johan De Witt found himself faced with a mob of angry demonstrators of sailors, however, even at the young age of 27 years, it was Johans coolheadedness that calmed the situation. Many people older than Johan began to see greatness in Johan dating from that experience, Johan de Witt married on 16 February 1655 Wendela Bicker, the daughter of Jan Bicker, an influential patrician from Amsterdam, and Agneta de Graeff van Polsbroek. Jan Bicker served as mayor of Amsterdam in 1653, De Witt became a relative to the strong republican-minded brothers Cornelis and Andries de Graeff, and to Andries Bicker. Heer van Zuid- en Noord-Linschoten, Snelrewaard and IJsselveere, married to Wilhelmina de Witt and he was secretary of the city of Dordrecht After De Witts death, his brother in law Pieter de Graeff became a guardian over his children. In 1653, the States of Holland elected De Witt councilor pensionary, the raadpensionaris of Holland was often referred to as the Grand Pensionary by foreigners as he represented the preponderant province in the Union of the Dutch Republic. He was a servant who lead the States of province by his experience, tenure, familiarity with the issues and he was in no manner equivalent to a modern Prime Minister. · Representing the province of Holland, Johan De Witt tended to identify with the interests of the shipping and trading interests in the United Provinces. These interests were largely concentrated in the province of Holland, not surprisingly, Johan de Witt also held views of toleration of religious beliefs. De Witts power base was the merchant class into which he was born. This class broadly coincided politically with the States faction, stressing Protestant religious moderation, William II of Orange was a prime example of this tendency among the leaders of the House of Orange to support Calvinism. William II was elected Stadholder in 1647 and continued to serve until his death in November,1650, eight days after his death, William IIs wife delivered a male heir--William III of Orange. Many citizens of the United Provinces urged the election of the infant William III as stadholder under a regency until he came of age, however, the Provinces, under the dominance of the province of Holland did not fill the office of Stadholder

Johan de Wit
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Johan de Witt

Johan de Wit
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Wendela Bicker (1659), by Adriaen Hanneman

Johan de Wit
–
Statue of Johan and Cornelis de Witt in Dordrecht

Johan de Wit

13.
Joan Hudde
–
Johannes Hudde was a burgomaster of Amsterdam between 1672 –1703, a mathematician and governor of the Dutch East India Company. He also promoted hygiene in and around the water supply. Huddes stones were stones that were used to mark the summer high water level at several points in the city. They later were the foundation for the NAP, the now Europe-wide system for measuring water levels, Hudde studied law at the University of Leiden, but turned to mathematics under the influence of his teacher Frans van Schooten. From 1654 to 1663 he worked under van Schooten and with his fellow students Johan de Witt, each of the students added to the work. Huddes contribution consisted of a study on maxima and minima and a theory of equations, Hudde corresponded with Baruch Spinoza and Christiaan Huygens, Johann Bernoulli, Isaac Newton and Leibniz. Newton and Leibniz mention Hudde many times and used some of his ideas in their own work on infinitesimal calculus, huddes rules OConnor, John J. Robertson, Edmund F. Johannes Hudde, MacTutor History of Mathematics archive, University of St Andrews

Joan Hudde
–
Johannes van Waveren Hudde

14.
Brouwerian
–
He was the founder of the mathematical philosophy of intuitionism. Early in his career, Brouwer proved a number of theorems that were in the field of topology. The main results were his fixed point theorem, the invariance of degree. The most popular of the three among mathematicians is the first one called the Brouwer Fixed Point Theorem and it is a simple corollary to the second, about the topological invariance of degree, and this one is the most popular among algebraic topologists. The third is perhaps the hardest, in 1912, at age 31, he was elected a member of the Royal Netherlands Academy of Arts and Sciences. As a variety of mathematics, intuitionism is essentially a philosophy of the foundations of mathematics. It is sometimes and rather simplistically characterized by saying that its adherents refuse to use the law of excluded middle in mathematical reasoning, Brouwer was a member of the Significs group. It formed part of the history of semiotics—the study of symbols—around Victoria. The original meaning of his intuitionism probably can not be completely disentangled from the milieu of that group. In 1905, at the age of 24, Brouwer expressed his philosophy of life in a short tract Life, Art, arthur Schopenhauer had a formative influence on Brouwer, not least because he insisted that all concepts be fundamentally based on sense intuitions. All interwoven with some kind of pessimism and mystical attitude to life which is not mathematics and it was then that Brouwer felt free to return to his revolutionary project which he was now calling intuitionism. He was combative for a young man and he was involved in a very public and eventually demeaning controversy in the later 1920s with Hilbert over editorial policy at Mathematische Annalen, at that time a leading learned journal. He became relatively isolated, the development of intuitionism at its source was taken up by his student Arend Heyting and he was killed in 1966 at the age of 85, struck by a vehicle while crossing the street in front of his house. Jean van Heijenoort,1967 3rd printing 1976 with corrections, A Source Book in Mathematical Logic, harvard University Press, Cambridge MA, ISBN 0-674-32449-8 pbk. The original papers are prefaced with valuable commentary, L. E. J. Brouwer, On the significance of the principle of excluded middle in mathematics, especially in function theory. With two Addenda and corrigenda, 334-45, a. N. Kolmogorov, On the principle of excluded middle, pp. 414–437. Kolmogorov supports most of Brouwers results but disputes a few, he discusses the ramifications of intuitionism with respect to transfinite judgements, L. E. J. Brouwer, On the domains of definition of functions. Brouwers intuitionistic treatment of the continuum, with an extended commentary, david Hilbert, The foundations of mathematics, 464-801927

Brouwerian
–
L. E. J. Brouwer

15.
Dick de Bruijn
–
Born in The Hague, De Bruijn received his MA in Mathematics at the Leiden University in 1941. He received his PhD in 1943 from Vrije Universiteit Amsterdam with a thesis entitled Over modulaire vormen van meer veranderlijken advised by Jurjen Ferdinand Koksma, De Bruijn started his academic career as at the University of Amsterdam, where he was Professor of Mathematics from 1952 to 1960. In 1960 he moved to the Technical University Eindhoven where he was Professor of Mathematics until his retirement in 1984, in 1957 he was appointed member of the Royal Netherlands Academy of Arts and Sciences. He was Knighted with the Order of the Netherlands Lion, De Bruijn covered many areas of mathematics. He wrote one of the books in advanced asymptotic analysis. In the late sixties, he designed the Automath language for representing mathematical proofs, shortly before his death, he had been working on models for the human brain. Over modulaire vormen van meer veranderlijken 1958, asymptotic Methods in Analysis, North-Holland, Amsterdam. Articles, a selection, de Bruijn, Nicolaas Govert, in Proceedings of the Section of Sciences, Vol.49, No. Koninklijke Nederlandse Akademie v. Wetenschappen. de Bruijn, Nicolaas Govert, the mathematical language AUTOMATH, its usage, and some of its extensions. Springer Berlin Heidelberg,1970. de Bruijn, Nicolaas Govert, lambda calculus notation with nameless dummies, a tool for automatic formula manipulation, with application to the Church-Rosser theorem. Moser–de Bruijn sequence Nicolaas Govert de Bruijns obituary Bruijn N. G. de at win. tue. nl

Dick de Bruijn
–
Nicolaas Govert de Bruijn

16.
Pierre Deligne
–
Pierre René, Viscount Deligne is a Belgian mathematician. He is known for work on the Weil conjectures, leading to a proof in 1973. He is the winner of the 2013 Abel Prize,2008 Wolf Prize and he was born in Etterbeek, attended school at Athénée Adolphe Max and studied at the Université libre de Bruxelles. In 1968, he worked with Jean-Pierre Serre, their work led to important results on the l-adic representations attached to modular forms. Delignes also focused on topics in Hodge theory and he introduced weights and tested them on objects in complex geometry. He also collaborated with David Mumford on a new description of the spaces for curves. Their work came to be seen as an introduction to one form of the theory of algebraic stacks, perhaps Delignes most famous contribution was his proof of the third and last of the Weil conjectures. This proof completed a programme initiated and largely developed by Alexander Grothendieck, as a corollary he proved the celebrated Ramanujan–Petersson conjecture for modular forms of weight greater than one, weight one was proved in his work with Serre. From 1970 until 1984, when he moved to the Institute for Advanced Study in Princeton, during this time he did much important work outside of his work on algebraic geometry. He received a Fields Medal in 1978 and this idea allows one to get around the lack of knowledge of the Hodge conjecture, for some applications. All this is part of the yoga of weights, uniting Hodge theory, the Shimura variety theory is related, by the idea that such varieties should parametrize not just good families of Hodge structures, but actual motives. This theory is not yet a finished product – and more recent trends have used K-theory approaches and he was awarded the Fields Medal in 1978, the Crafoord Prize in 1988, the Balzan Prize in 2004, the Wolf Prize in 2008, and the Abel Prize in 2013. In 2006 he was ennobled by the Belgian king as viscount, in 2009, Deligne was elected a foreign member of the Royal Swedish Academy of Sciences. He is a member of the Norwegian Academy of Science and Letters, Quantum fields and strings, a course for mathematicians. Material from the Special Year on Quantum Field Theory held at the Institute for Advanced Study, Princeton, NJ, edited by Pierre Deligne, Pavel Etingof, Daniel S. Freed, Lisa C. Jeffrey, David Kazhdan, John W. Morgan, David R. Morrison, american Mathematical Society, Providence, RI, Institute for Advanced Study, Princeton, NJ,1999. Vol.1, xxii+723 pp. Vol.2, pp. i--xxiv, Deligne wrote multiple hand-written letters to other mathematicians in the 1970s. These include Delignes letter to Piatetskii-Shapiro and it was proved by Kontsevich–Soibelman, McClure–Smith and others

Pierre Deligne
–
Pierre Deligne, March 2005

17.
Adequacy Principle
–
René Descartes was a French philosopher, mathematician, and scientist. Dubbed the father of western philosophy, much of subsequent Western philosophy is a response to his writings. A native of the Kingdom of France, he spent about 20 years of his life in the Dutch Republic, descartess Meditations on First Philosophy continues to be a standard text at most university philosophy departments. He is credited as the father of geometry, the bridge between algebra and geometry, used in the discovery of infinitesimal calculus and analysis. Descartes was also one of the key figures in the scientific revolution, Descartes refused to accept the authority of previous philosophers. He frequently set his views apart from those of his predecessors and his best known philosophical statement is Cogito ergo sum, found in part IV of Discourse on the Method and §7 of part I of Principles of Philosophy. Many elements of his philosophy have precedents in late Aristotelianism, the revived Stoicism of the 16th century, in his theology, he insists on the absolute freedom of Gods act of creation. Leibniz, Spinoza and Descartes were all well-versed in mathematics as well as philosophy, Descartes was born in La Haye en Touraine, France, on 31 March 1596. When he was one old, his mother Jeanne Brochard died after trying to give birth to another child who also died. His father Joachim was a member of the Parlement of Brittany at Rennes, rené lived with his grandmother and with his great-uncle. Although the Descartes family was Roman Catholic, the Poitou region was controlled by the Protestant Huguenots, in 1607, late because of his fragile health, he entered the Jesuit Collège Royal Henry-Le-Grand at La Flèche where he was introduced to mathematics and physics, including Galileos work. From there he moved to Paris, in his book Discourse on the Method, Descartes recalls, I entirely abandoned the study of letters. Descartes, therefore, received encouragement in Breda to advance his knowledge of mathematics. In this way, he acquainted with Isaac Beeckman, principal of a Dordrecht school. Together they worked on free fall, catenary, conic section, both believed that it was necessary to create a method that thoroughly linked mathematics and physics. While in the service of Duke Maximilian of Bavaria since 1619, Descartes was present at the Battle of the White Mountain outside Prague and he visited the labs of Tycho Brahe in Prague and Johannes Kepler in Regensburg. According to Adrien Baillet, on the night of 10–11 November 1619, while stationed in Neuburg an der Donau, while within, he had three visions and believed that a divine spirit revealed to him a new philosophy. Upon exiting, he had formulated analytical geometry and the idea of applying the method to philosophy

Adequacy Principle
–
Portrait after

Frans Hals, 1648

Adequacy Principle
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The house where he was born in

La Haye en Touraine
Adequacy Principle
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Graduation registry for Descartes at the

Collège Royal Henry-Le-Grand,

La Flèche, 1616

18.
Seven Netherlands
–
It preceded the Batavian Republic, the Kingdom of Holland, the United Kingdom of the Netherlands, and ultimately the modern Kingdom of the Netherlands. Alternative names include the United Provinces, Seven Provinces, Federated Dutch Provinces, most of the Low Countries had come under the rule of the House of Burgundy and subsequently the House of Habsburg. In 1549 Holy Roman Emperor Charles V issued the Pragmatic Sanction, Charles was succeeded by his son, King Philip II of Spain. This was the start of the Eighty Years War, in 1579 a number of the northern provinces of the Low Countries signed the Union of Utrecht, in which they promised to support each other in their defence against the Spanish army. This was followed in 1581 by the Act of Abjuration, the declaration of independence of the provinces from Philip II. In 1582 the United Provinces invited Francis, Duke of Anjou to lead them, but after an attempt to take Antwerp in 1583. After the assassination of William of Orange, both Henry III of France and Elizabeth I of England declined the offer of sovereignty, however, the latter agreed to turn the United Provinces into a protectorate of England, and sent the Earl of Leicester as governor-general. This was unsuccessful and in 1588 the provinces became a confederacy, the Union of Utrecht is regarded as the foundation of the Republic of the Seven United Provinces, which was not recognized by the Spanish Empire until the Peace of Westphalia in 1648. During the Anglo-French war, the territory was divided into groups, the Patriots, who were pro-French and pro-American and the Orangists. The Republic of the United Provinces faced a series of revolutions in 1783–1787. During this period, republican forces occupied several major Dutch cities, initially on the defence, the Orangist forces received aid from Prussian troops and retook the Netherlands in 1787. After the French Republic became the French Empire under Napoleon, the Batavian Republic was replaced by the Napoleonic Kingdom of Holland, the Netherlands regained independence from France in 1813. In the Anglo-Dutch Treaty of 1814 the names United Provinces of the Netherlands, on 16 March 1815, the son of stadtholder William V crowned himself King William I of the Netherlands. Between 1815 and 1890 the King of the Netherlands was also in a union the Grand Duke of the sovereign Grand Duchy of Luxembourg. After Belgium gained its independence in 1830, the state became known as the Kingdom of the Netherlands. The County of Holland was the wealthiest and most urbanized region in the world, the free trade spirit of the time received a strong augmentation through the development of a modern, effective stock market in the Low Countries. The Netherlands has the oldest stock exchange in the world, founded in 1602 by the Dutch East India Company, while Rotterdam has the oldest bourse in the Netherlands, the worlds first stock exchange, that of the Dutch East-India Company, went public in six different cities. Later, a court ruled that the company had to reside legally in a city so Amsterdam is recognized as the oldest such institution based on modern trading principles

Seven Netherlands
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Dutch East-India trading ship 1600

Seven Netherlands
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Flag
Seven Netherlands
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Onrust Island near

Batavia, 1699

Seven Netherlands
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Courtyard of the Amsterdam Stock Exchange, 1653

19.
Universiteit groningen
–
The University of Groningen is a public research university in the city of Groningen in the Netherlands. The university was founded in 1614 and is one of the oldest universities in the Netherlands as well as one of its largest, since its inception more than 200,000 students have graduated. It is a member of the distinguished international Coimbra Group of European universities, in April 2013, according to the results of the International Student Barometer, the University of Groningen, for the third time in a row, has been voted the best university of the Netherlands. In 2014 the university celebrated its 400th anniversary, the University of Groningen has ten faculties, nine graduate schools,27 research centres and institutes, and more than 175 degree programmes. There were four faculties – Theology, Law, Medicine, the coat of arms of the university was confirmed by the States of the City and County of Groningen in 1615. It consists of the arms, charged with an open book inscribed with the abbreviated words VER/BVM/DNI LV/CER/NA. The shield is surmounted by a crown of five leaves. The first 75 years of its existence were very fruitful for the University with about 100 students enrolling every year, on average two to three hundred students were registered with the University at any one time during this period. Opportunities and threats followed on each other’s heels during the nineteenth century, in 1815, at the same time as Leiden and Utrecht, the University gained recognition as a national college of higher education, but this was followed by discussions about closure. The situation improved markedly when a new university building, the Academiegebouw, was constructed in 1850. This made the fire completely destroyed this building in 1906 even more poignant. In the meantime, the Higher Education Act of 1876 had radically improved the position of the University, teaching now took place in Dutch as well as in Latin and the University was given a research as well as an educational duty. This laid the foundations for the present research university, the University of Groningen developed apace during the first decades of the twentieth century. The number of faculties and courses grew steadily while the number of students showed an explosive growth, when the University celebrated its first 300 years in 1914 there were 611 registered students, this had already grown to 1000 by 1924. After a drop back during the Depression, and in particular during the Second World War, in 2016 the Dutch chemist Ben Feringa, who worked most of his career at the university, won the Nobel prize for his work on molecular motors. Other strong research groups are in, Nanoscience, Physics, Molecular Biology, Microbiology, Medical Sciences, Neurosciences, Sociology, Philosophy, Theology, Archaeology and Arts. Every year more than 5,000 research publications go to print, the University of Groningen is a member of the so-called Excellence Group of the best universities in Europe. The Excellence Group has 56 members, which is 1.3 percent of the approximately 4,500 European institutions of higher education, the University of Groningen belongs to the top 100 large comprehensive research universities in the world

Universiteit groningen
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Front of the main building ('Academiegebouw') of the University of Groningen

Universiteit groningen
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University of Groningen

Universiteit groningen
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The Senate room in the Academy Building

Universiteit groningen
–
Bernoulliborg

20.
Epitaph of Stevinus
–
Simon Stevin, sometimes called Stevinus, was a Flemish/Dutch/Netherlandish mathematician, physicist and engineer. He was active in a great areas of science and engineering. Very little is known with certainty about Stevins life and what we know is mostly inferred from other recorded facts, the exact birth date and the date and place of his death are uncertain. It is assumed he was born in Bruges since he enrolled at Leiden University under the name Simon Stevinus Brugensis and his name is usually written as Stevin, but some documents regarding his father use the spelling Stevijn. This is a normal spelling shift in 16th century Dutch and he was born around the year 1548 to unmarried parents, Anthonis Stevin and Catelyne van der Poort. His father is believed to have been a son of a mayor of Veurne. While Simons father was not mentioned in the book of burghers, many other Stevins were later mentioned in the Poorterboeken. Simon Stevins mother Cathelijne was the daughter of a family from Ypres. Her father Hubert was a poorter of Bruges, Simons mother Cathelijne later married Joost Sayon who was involved in the carpet and silk trade and a member of the schuttersgilde Sint-Sebastiaan. Through her marriage Cathelijne became a member of a family of Calvinists and it is believed that Stevin grew up in a relatively affluent environment and enjoyed a good education. He was likely educated at a Latin school in his hometown, Stevin left Bruges in 1571 apparently without a particular destination. Stevin was most likely a Calvinist since a Catholic would likely not have risen to the position of trust he later occupied with Maurice, Prince of Orange and it is assumed that he left Bruges to escape the religious persecution of Protestants by the Spanish rulers. Based on references in his work Wisconstighe Ghedaechtenissen, it has been inferred that he must have moved first to Antwerp where he began his career as a merchants clerk. Some biographers mention that he travelled to Prussia, Poland, Denmark, Norway and Sweden and other parts of Northern Europe and it is possible that he completed these travels over a longer period of time. In 1577 Simon Stevin returned to Bruges and was appointed city clerk by the aldermen of Bruges and he worked in the office of Jan de Brune of the Brugse Vrije, the castellany of Bruges. Why he had returned to Bruges in 1577 is not clear and it may have been related to the political events of that period. Bruges was the scene of religious conflict. Catholics and Calvinists alternately controlled the government of the city and they usually opposed each other but would occasionally collaborate in order to counteract the dictates of King Philip II of Spain

Epitaph of Stevinus
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Simon Stevin

Epitaph of Stevinus
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Statue of Simon Stevin by

Eugène Simonis, on the Simon Stevinplein (nl) in

Bruges
Epitaph of Stevinus
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Statue of Stevin (detail)

Epitaph of Stevinus
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Statue (detail):

Inclined plane diagram
21.
T. J. Stieltjes
–
Thomas Joannes Stieltjes was a Dutch mathematician. He was born in Zwolle and died in Toulouse, France and he was a pioneer in the field of moment problems and contributed to the study of continued fractions. The Thomas Stieltjes Institute for Mathematics at the University of Leiden, dissolved in 2011, was named after him, Stieltjes was born in Zwolle on 29 December 1856. His father was a engineer and politician. Stieltjes Sr. was responsible for the construction of various harbours around Rotterdam, Stieltjes Jr. went to university at the Polytechnical School in Delft in 1873. Instead of attending lectures, he spent his student years reading the works of Gauss, there were 2 further failures, and his father despaired. His father was friends with H. G. van de Sande Bakhuyzen, soon afterwards, Stieltjes began a correspondence with Charles Hermite which lasted for the rest of his life. Stieltjes originally wrote to Hermite concerning celestial mechanics, but the subject turned to mathematics. The director of Leiden Observatory, van de Sande-Bakhuyzen, responded quickly to Stieltjes request on 1 January 1883 to stop his work to allow him to work more on mathematical topics. In 1883, he also married Elizabeth Intveld in May and she also encouraged him to move from astronomy to mathematics. And in September, Stieltjes was asked to substitute at University of Delft for F J van den Berg, from then until December of that year, he lectured on analytical geometry and on descriptive geometry. He resigned his post at the observatory at the end of that year, in 1884, Stieltjes applied for a chair in Groningen. He was initially accepted, but in the end turned down by the Department of Education, in 1884, Hermite and professor David Bierens de Haan arranged for an honorary doctorate to be granted to Stieltjes by Leiden University, enabling him to become a professor. In 1885, he was appointed as member of the Royal Dutch Academy of Sciences, in 1889, he was appointed professor of differential and integral calculus at Toulouse University. Stieltjes worked on almost all branches of analysis, continued fractions and number theory and his work is also seen as important as a first step towards the theory of Hilbert spaces. Other important contributions to mathematics that he made involved discontinuous functions and divergent series, differential equations, interpolation, Stieltjes work on continued fractions earned him the Ormoy Prize of the Académie des Sciences. Robertson, Edmund F. Thomas Joannes Stieltjes, MacTutor History of Mathematics archive, Thomas Joannes Stieltjes at the Mathematics Genealogy Project Œuvres complètes de Thomas Jan Stieltjes, pub. par les soins de la Société mathématique dAmsterdam

T. J. Stieltjes
–
Thomas Joannes Stieltjes

22.
Basic theories of science
–
Science is a systematic enterprise that builds and organizes knowledge in the form of testable explanations and predictions about the universe. The formal sciences are often excluded as they do not depend on empirical observations, disciplines which use science, like engineering and medicine, may also be considered to be applied sciences. However, during the Islamic Golden Age foundations for the method were laid by Ibn al-Haytham in his Book of Optics. In the 17th and 18th centuries, scientists increasingly sought to formulate knowledge in terms of physical laws, over the course of the 19th century, the word science became increasingly associated with the scientific method itself as a disciplined way to study the natural world. It was during this time that scientific disciplines such as biology, chemistry, Science in a broad sense existed before the modern era and in many historical civilizations. Modern science is distinct in its approach and successful in its results, Science in its original sense was a word for a type of knowledge rather than a specialized word for the pursuit of such knowledge. In particular, it was the type of knowledge which people can communicate to each other, for example, knowledge about the working of natural things was gathered long before recorded history and led to the development of complex abstract thought. This is shown by the construction of calendars, techniques for making poisonous plants edible. For this reason, it is claimed these men were the first philosophers in the strict sense and they were mainly speculators or theorists, particularly interested in astronomy. In contrast, trying to use knowledge of nature to imitate nature was seen by scientists as a more appropriate interest for lower class artisans. A clear-cut distinction between formal and empirical science was made by the pre-Socratic philosopher Parmenides, although his work Peri Physeos is a poem, it may be viewed as an epistemological essay on method in natural science. Parmenides ἐὸν may refer to a system or calculus which can describe nature more precisely than natural languages. Physis may be identical to ἐὸν and he criticized the older type of study of physics as too purely speculative and lacking in self-criticism. He was particularly concerned that some of the early physicists treated nature as if it could be assumed that it had no intelligent order, explaining things merely in terms of motion and matter. The study of things had been the realm of mythology and tradition, however. Aristotle later created a less controversial systematic programme of Socratic philosophy which was teleological and he rejected many of the conclusions of earlier scientists. For example, in his physics, the sun goes around the earth, each thing has a formal cause and final cause and a role in the rational cosmic order. Motion and change is described as the actualization of potentials already in things, while the Socratics insisted that philosophy should be used to consider the practical question of the best way to live for a human being, they did not argue for any other types of applied science

Basic theories of science
–

Maize, known in some English-speaking countries as corn, is a large

grain plant domesticated by

indigenous peoples in

Mesoamerica in

prehistoric times.

Basic theories of science
–
The scale of the universe mapped to the branches of science and the hierarchy of science.

Basic theories of science
–

Aristotle, 384 BC – 322 BC, - one of the early figures in the development of the

scientific method.

Basic theories of science
–

Galen (129—c.216) noted the optic chiasm is X-shaped. (Engraving from

Vesalius, 1543)

23.
Commons.wikimedia.org
–
Wikimedia Commons is an online repository of free-use images, sound, and other media files. It is a project of the Wikimedia Foundation, the repository contains over 38 million media files. In July 2013, the number of edits on Commons reached 100,000,000, the project was proposed by Erik Möller in March 2004 and launched on September 7,2004. The expression educational is to be according to its broad meaning of providing knowledge. Wikimedia Commons itself does not allow fair use or uploads under non-free licenses, for this reason, Wikimedia Commons always hosts freely licensed media and deletes copyright violations. The default language for Commons is English, but registered users can customize their interface to use any other user interface translations. Many content pages, in particular policy pages and portals, have also translated into various languages. Files on Wikimedia Commons are categorized using MediaWikis category system, in addition, they are often collected on individual topical gallery pages. While the project was proposed to also contain free text files. In 2012, BuzzFeed described Wikimedia Commons as littered with dicks, in 2010, Wikipedia co-founder Larry Sanger reported Wikimedia Commons to the FBI for hosting sexualized images of children known as lolicon. Wales responded to the backlash from the Commons community by voluntarily relinquishing some site privileges, over time, additional functionality has been developed to interface Wikimedia Commons with the other Wikimedia projects. Specialized uploading tools and scripts such as Commonist have been created to simplify the process of uploading large numbers of files. In order to free content photos uploaded to Flickr, users can participate in a defunct collaborative external review process. The site has three mechanisms for recognizing quality works, one is known as Featured pictures, where works are nominated and other community members vote to accept or reject the nomination. This process began in November 2004, another process known as Quality images began in June 2006, and has a simpler nomination process comparable to Featured pictures. Quality images only accepts works created by Wikimedia users, whereas Featured pictures additionally accepts nominations of works by third parties such as NASA, the three mentioned processes select a slight part from the total number of files. However, Commons collects files of all quality levels, from the most professional level across simple documental, files with specific defects can be tagged for improvement and warning or even proposed for deletion but there exists no process of systematic rating of all files. The site held its inaugural Picture of the Year competition, for 2006, all images that were made a Featured picture during 2006 were eligible, and voted on by eligible Wikimedia users during two rounds of voting

Commons.wikimedia.org

Commons.wikimedia.org
–
Wikimedia Commons

Commons.wikimedia.org

Commons.wikimedia.org

24.
Change (mathematics)
–
Mathematics is the study of topics such as quantity, structure, space, and change. There is a range of views among mathematicians and philosophers as to the exact scope, Mathematicians seek out patterns and use them to formulate new conjectures. Mathematicians resolve the truth or falsity of conjectures by mathematical proof, when mathematical structures are good models of real phenomena, then mathematical reasoning can provide insight or predictions about nature. Through the use of abstraction and logic, mathematics developed from counting, calculation, measurement, practical mathematics has been a human activity from as far back as written records exist. The research required to solve mathematical problems can take years or even centuries of sustained inquiry, rigorous arguments first appeared in Greek mathematics, most notably in Euclids Elements. Galileo Galilei said, The universe cannot be read until we have learned the language and it is written in mathematical language, and the letters are triangles, circles and other geometrical figures, without which means it is humanly impossible to comprehend a single word. Without these, one is wandering about in a dark labyrinth, carl Friedrich Gauss referred to mathematics as the Queen of the Sciences. Benjamin Peirce called mathematics the science that draws necessary conclusions, David Hilbert said of mathematics, We are not speaking here of arbitrariness in any sense. Mathematics is not like a game whose tasks are determined by arbitrarily stipulated rules, rather, it is a conceptual system possessing internal necessity that can only be so and by no means otherwise. Albert Einstein stated that as far as the laws of mathematics refer to reality, they are not certain, Mathematics is essential in many fields, including natural science, engineering, medicine, finance and the social sciences. Applied mathematics has led to entirely new mathematical disciplines, such as statistics, Mathematicians also engage in pure mathematics, or mathematics for its own sake, without having any application in mind. There is no clear line separating pure and applied mathematics, the history of mathematics can be seen as an ever-increasing series of abstractions. The earliest uses of mathematics were in trading, land measurement, painting and weaving patterns, in Babylonian mathematics elementary arithmetic first appears in the archaeological record. Numeracy pre-dated writing and numeral systems have many and diverse. Between 600 and 300 BC the Ancient Greeks began a study of mathematics in its own right with Greek mathematics. Mathematics has since been extended, and there has been a fruitful interaction between mathematics and science, to the benefit of both. Mathematical discoveries continue to be made today, the overwhelming majority of works in this ocean contain new mathematical theorems and their proofs. The word máthēma is derived from μανθάνω, while the modern Greek equivalent is μαθαίνω, in Greece, the word for mathematics came to have the narrower and more technical meaning mathematical study even in Classical times

Change (mathematics)
–

Euclid (holding

calipers), Greek mathematician, 3rd century BC, as imagined by

Raphael in this detail from

The School of Athens.

Change (mathematics)
–
Greek mathematician

Pythagoras (c. 570 – c. 495 BC), commonly credited with discovering the

Pythagorean theorem
Change (mathematics)
–

Leonardo Fibonacci, the

Italian mathematician who established the Hindu–Arabic numeral system to the Western World

Change (mathematics)
–

Carl Friedrich Gauss, known as the prince of mathematicians