Ehrenfried Walther von Tschirnhaus

Ehrenfried Walther von Tschirnhaus, engraving by Martin Bernigeroth

Ehrenfried Walther von Tschirnhaus (also Tschirnhauß, incorrectly Tschirnhausen; born  April 10, 1651 in Kieslingswalde ; †  October 11, 1708 in Dresden ) was a German natural scientist (didactic, mathematician, mineralogist, philosopher, physicist, technician, volcanologist) at the beginning of the era the enlightenment .

The writings, the correspondence and the physical objects provide information about the work and the perception of his person by the learned republic of the 17th and 18th centuries in Europe. His thinking was based on Cartesianism . His works are attributed to the Early Enlightenment . Tschirnhaus saw the application and perfection of algebra as a method of ars inveniendi as a universal method for scientific knowledge. Noteworthy and controversial are the conclusions that he reached using the propagated method of knowledge.

Medicina mentis (BEIC)

The results of his research promoted the development of laboratory investigation methods, materials research, foundries and metallurgy and optical device construction. His technological innovations fertilized the further development of the Saxon manufactory .

Life

Ehrenfried Walther von Tschirnhaus was born as the seventh child, three years after the end of the Thirty Years' War in the margraviate of Upper Lusatia . His mother was Elisabeth Eleonore Freiin Achil von Stirling, his father was the electoral Saxon councilor Christoph von Tschirnhaus. After his mother's death in 1657, he was raised by stepmother Anna von Nostitz.

Kieslingswalde estate near Görlitz around 1870, Alexander Duncker collection

Tschirnhaus grew up in Upper Lusatia, which was shaped by numerous Protestant religious refugees from Bohemia and Moravia . The region, which suffered from the consequences of the war, was one of the regions with the highest population density in Saxony, despite the loss of around two thirds of its inhabitants. In 1623 this was pledged by Emperor Ferdinand II to the allied Protestant Elector Johann Georg I and in 1635 it was annexed to Electoral Saxony .

Tschirnhaus received a mathematical and scientific training from private tutors . He attended Nathanael Heer's school in Lauban and the grammar school in Görlitz . The history of the city of Görlitz, which belonged to the Upper Lusatian Six Cities Association, was influenced by the culture of the utraquist estates of Bohemia . Apparently Tschirnhaus already occupied himself with the work of Johann Heinrich Alsted , Johann Amos Comenius as a pupil and probably also knew the writings of Jakob Boehme . The works of Reformed theologians who represented the systematic thinking of the Baroque era were just as well known to the young Tschirnhaus as those of the Jesuit Athanasius Kircher .

1669–1674 studied in Leiden

In the winter of 1668 he traveled to Leiden to study, but immediately fell ill with typhus, which was currently rampant . Recovered, Tschirnhaus enrolled on June 8, 1669 at the University of Leiden to study law . However, his main interests were in mathematics , philosophy, and physics . He heard from the philosopher Arnold Geulincx and from the medic de la Boe (Sylvius), who taught William Harvey's doctrine of blood circulation. He took private mathematics lessons from Pieter van Schooten and was introduced to the teachings of René Descartes , whose enthusiastic supporter he would remain throughout his life.

From 1672 Tschirnhaus, like many of his classmates, took on the side of the Dutch governor Wilhelm III under the command of Baron von Nieuwland for one and a half years . of Orange-Nassau participated in the Dutch War prepared by France and supported by England . But he was not involved in direct combat operations. In spring 1674 he finished his studies and returned to Kieslingswalde.

1675–1676 educational trip to England and France

Tschirnhaus began his Grand Tour at the turn of the year 1674/1675 . The stations of this journey, which Tschirnhaus took to the scientific centers of Europe, shaped his later research. In the Netherlands, Tschirnhaus made contact with Baruch Spinoza, who lived in The Hague , during his studies . Equipped with a letter of recommendation from Spinoza, he traveled to London for three months in May 1675. There he visited the Secretary of the Royal Society Henry Oldenbourg . He put the self-confident Tschirnhaus in touch with Robert Boyle and John Wallis , Denis Papin and Christopher Wren . John Collins later describes Tschirnhaus to James Gregory , who, like Isaac Newton, works on the construction of mirror telescopes , as the most knowing algebraist in Europe. John Pell even refused to talk to Tschirnhaus about mathematical questions so that he would not be suspected of having copied from him.

Oldenbourg gave Tschirnhaus letters of recommendation for scientists living in Paris . Once there, he met Gottfried Wilhelm Leibniz and Christiaan Huygens , who had also studied in Leiden. Huygens had been a member of the Royal Society since 1660 . Like Newton, he worked on the construction of optical instruments and researched questions of diffraction , refraction and reflection of light, which later become part of his elementary wave theory. On Huygen's recommendation, Tschirnhaus temporarily worked as a private tutor to the French Finance Minister Colbert , the founder of the Paris Academy of Sciences . Tschirnhaus taught Colbert's son mathematics, although he had to use the Latin language, as he hardly spoke French. He came into contact with Antoine Arnauld , Nicolas Malebranche and Edme Mariotte . In September 1675 he participated in melting experiments that were carried out with a burning mirror .

At the side of Leibniz, who was sent to Paris by Johann Philipp von Schönborn , Tschirnhaus worked on problems in algebra, as well as on geometry and number theory . Tschirnhaus, however, was not willing to follow the infinitesimal calculus developed by Leibniz . He favored a descriptive method for handling geometrical-algebraic facts. This view, based on Cartesianism , which Tschirnhaus saw himself to be the perfecter, disappointed Leibniz's expectations, which he had linked to mathematical talent. In October Tschirnhaus discovered a new equation method, the Tschirnhaus transformation . In November 1676 Tschirnhaus continued his study trip. From Paris it went to the designer of the Parisian focal mirror, the physicist François Villette in Lyon . Tschirnhaus sees more burning mirrors and experiments by Villette there.

1677–1679 study trip to Italy

Kircher's model of underground fires, illustration from Mundus Subterraneus

In the wake of the Silesian Count Nimptsch , his journey from Lyon via Turin to Milan led to Manfredo Settala and his collection of instruments, which included a burning mirror with a diameter of 119 cm. After the stops in Venice and Bologna , he reached Rome in 1677 . Tschirnhaus met Giovanni Alfonso Borelli here , whom he asked about grinding techniques. Borelli was a student of Michelangelo Ricci and a friend of Evangelista Torricelli and Athanasius Kircher . The latter had published six years earlier in the Ars magna lucis et umbrae on antique burning mirrors. His work Mundus subterraneus on volcanology was about to be completed. He was also the founder of the Museum Kircherianum , the important baroque cabinet of curiosities that the Collegium Romanum used for teaching purposes. Tschirnhaus met Kircher for the first time in April 1677 and received many suggestions from him. In the spring of 1677 Tschirnhaus traveled to Naples. After studying on Vesuvius , he continued his journey via Palermo in order to conduct research on volcanology and the volcanic rock obsidian on Mount Etna and on the Aeolian Islands on Stromboli .

After a detour to Malta, Tschirnhaus traveled via Milan and Geneva back to Paris, where he arrived at the beginning of 1679. There Tschirnhaus got an insight into Huygens' completed work on wave optics, which is known today as Huygens principle . He also experienced the mode of action of a new, large Villette mirror. In late summer he traveled to Leiden and worked on the publication of Spinoza's posthumous manuscripts. Via Hanover, where he visited Leibniz, he reached Kieslingswalde in October 1679.

1679–1687 Development of the burning mirror

Spherical burning mirror by Tschirnhaus from 1686 in the Mathematisch-Physikalischer Salon in Dresden. One of his focal lens devices is in the background

From 1679 Tschirnhaus worked together with the mechanic Johann Hoffmann on the construction of burning mirrors. Tschirnhaus simplified the production of the mirrors, which were previously cast from metal alloys. By driving prefabricated sheets from copper hammers from the Ore Mountains , the inexpensive manufacture of mirror devices was possible. The copper caps were light and easy to polish afterwards. Optimized in terms of reflectivity, the concave concave mirrors were inserted into circular wooden frames. Set up on a tripod, they were easily adjustable.

Their goal was to use the profits from the sale of the instruments to finance future research and the establishment of a scientific and technical academy in Kieslingswalde. Trips to Paris made between 1681 and 1682 should also help. On the recommendation of Jean-Baptiste Colbert, Tschirnhaus was accepted into the Académie des sciences on July 22, 1682 as académicien géomètre . He dedicated the first part of the “Medicina mentis” published in 1686 to Louis XIV. In this way he hoped to receive a pension from the king as a member of the academy. Both hopes were not fulfilled.

In addition to Spinoza, Huygens and Oldenburg, Tschirnhaus maintained extensive correspondence with pioneers of the early enlightenment such as Friedrich Hoffmann , Adam Rechenberg and Otto Mencke .

Tschirnhaus married Elisabeth Eleonoren von Lest in 1682 . The marriage had five children. With the death of his father in 1684, Tschirnhaus took over the management of the estate, which, however, he left almost entirely to his wife while he devoted himself to scientific work. The appointment as chancellor of the newly founded university of the city of Halle (Saale) , which had fallen to the Electorate of Brandenburg in 1680 , turned out Tschirnhaus as well as the participation in the establishment of manufactories of the Landgrave Karl von Hessen-Kassel .

In 1687, the work on mirror devices was completed. The number of burning mirrors manufactured in Kieslingswalde is not known. The goal associated with their production of achieving economic independence was not fulfilled. The instruments were used in optical, acoustic, medical and material-technical experiments. In addition, they found their way into the art chambers of European royal courts as aesthetic and representative collector's items. The work on the solar ovens went beyond mere replica and improvement of the existing technology. His burning mirrors and glasses were essential for the following investigations into the production of porcelain, as he was able to achieve the required high temperatures of 1400 ° C with relatively little effort.

Excursus: china trade and European imitations

A suggestion for this came from my studies at the center of Dutch faience production . The porcelain that had come to Europe since the 13th century was increasingly imported from 1516 via Macau and Nagasaki to Lisbon, and in the 17th century almost exclusively via Holland. The economic success of the imports of the Vereenigde Oostindische Compagnie of an estimated 12 million pieces of Chinese porcelain from the Ming dynasty and Japanese porcelain from the Edo period was also evident for Tschirnhaus.

As a result of Marco Polo's travelogues “ Il Milione ” , attempts had been made to produce Qingbai porcelain in Europe. The surogates developed in the process were created in the process of glass - or as faience production . In the Republic of Venice , the Lattimo was made in Murano in the 15th century . This opaque glass was created by adding bone ash , leg glass or tin oxide as an opacifier and imitating porcelain. While in Faenza , which belonged to the Republic of Venice southeast of Bologna, the Bianchi di Faenza was made in the 16th century . In contrast to the leg glass, this was made of ceramic. In order to conceal the color that was different from the porcelain after the fire and to achieve a painting base suitable for decoration, it had to be coated with a tin glaze. Therefore, porcelain looked more appealing than the thicker-walled faience products.

Largest focal lens apparatus from Tschirnhaus (height 2.23 m)

1687–1692 Development of the lens apparatus

From 1687 on, Tschirnhaus concentrated on the development of larger glass burning lenses . A prerequisite for this was the production of large pieces of glass whose quality was sufficient for technical glass. The work was carried out with the assistance of the chemist Friedrich Schmied . Experience gained in grinding focal mirrors flowed into the subsequent processing of the lenses. By combining them into collective lenses , Tschirnhaus achieved an increase in the energy concentration in the focal point. Tschirnhaus also carried out mathematical investigations into the course of the light rays in focal lenses and mirrors (envelopes of the reflected rays, the so-called "catacaustics").

1692–1697 Improvement of glass casting and grinding technology

In addition to the laboratory, three glassworks and a grinding mill were available for research in Kieslingswalde. In exchange with the Leipzig university professor Martin Knorr , who comes from Wittenberg , improvements in grinding technologies could be tested and optical instruments could be produced individually. While many of the casting tests were carried out in the glassworks in Pretzsch near Wittenberg, which existed between 1692 and 1712, the grinding process in Kieslingswalde was strictly confidential.

Tschirnhaus published the results of the new glass casting method in the scientific journal Acta Eruditorum published in Leipzig in 1691 and described the effect of the burning glasses. In the same year, the casting process for the production of larger flat and mirror glasses reached technological maturity in France. Since 1687, Abraham Thewart and the mill director of the Manufactures des Glaces et des Produits Chimiques de St. Gobain, Chauny et Circy à Paris Louis-Lucas de Néhou had worked on the development of the process .

The glass quality could be improved after 1687 and made the production of optical glasses possible on a larger scale. Previous products from local smelters or the Leipzig Trade Fair were largely unsuitable due to imaging errors from impurities, color defects and their processing properties during grinding.

From 1692 Tschirnhaus entered the service of Johann Georg IV. He was appointed King. Polish Elector Saxon council and head of the electoral laboratories and succeeded the alchemist and glassmaker Johann Kunckel . He worked in the laboratory under Johann Georg II until 1677 and is considered the inventor of the gold ruby ​​glass . The appointment was based on his scientific and technical achievements and enabled the funding of further research. Even the assumption of government of Johann Georg's brother, Elector Friedrich August I , initially did not result in any major change in the status of Tschirnhaus.

In 1693 Tschirnhaus lost his wife, with whom he had five children, and a son. The attempts to melt slurried clay and loam, which began in 1693, could have already served to find porcelain. In 1694 he indicated to Leibniz the development of a new grinding machine with which very small and large Lentes Opticas for use in perspective glasses and burning glasses can be produced. He described the effect of new aggregates on glass production and the effect of lenses on enamel samples. Two trips to Leibniz in Hanover in 1694 served the purpose of finding buyers for his products. His perfected instruments gained greater fame through the experiments of the Italian scientists Giuseppe Averani and Cipriano Targioni in Florence in 1695.

Excursus: State and economic policy after 1694

The economic strength in Electoral Saxony was the result of the rich income from mining, which had been developing since the second half of the 12th century. Despite the decline in silver prices in the 17th century due to gold and silver imports from American and Japanese mines and the lower profits due to more difficult mining conditions, mining was the reason why the consequences of the Thirty Years War were faster here than in other states of the Holy Roman Empire of the German nation have been overcome. In the field of mining, a large number of handicraft and industrial branches had developed and promoted the development of the means of production and productive forces .

As a result of the relocation of trade routes in the 17th century, the wealthy southern German merchants were largely ousted by Upper German and Hanseatic merchants. In addition, a sovereignly controlled state economic development scheme based on the French model began to establish itself in Saxony. The under Johann Georg III. Reforms that had begun, such as the definition of the Leipzig mint foot in the mint treaty with Brandenburg-Prussia and the Duchy of Braunschweig-Lüneburg , were continued.

With August II., Electoral Saxony rose to the rank of kingdom in 1696 through the acquisition of the crown of the Polish-Lithuanian aristocratic republic . This gain in status was followed by the efforts of August II to organize the state in an absolutist way, following the example of France. The reforms were aimed at centralizing and standardizing the administrative structures. The establishment of a general revision board, which examined the tax administration, created the basis for tax reforms, which in 1707 led to the introduction of the general consumption tax . The promotion of a mercantilist economic policy led to the strengthening of the internal market .

The ignorance of economic interrelationships led to curbing money outflows from publishers in particular . The establishment of factories to limit exports of cheap raw materials and unprocessed semi-finished products was seen as an effective measure. The deposit bank founded in Leipzig in 1698/99 was supposed to provide part of the required free capital.

From 1696 on, Tschirnhaus sought funds from King August II to set up glassworks and a porcelain factory. During this time Tschirnhaus was commissioned with the investigation and inventory of Saxon minerals in order to visit the gemstone quarries of jasper , agate , amethysts and topazes in all places in Saxony .

1697–1700 establishment of glass factories

From 1697 the Constantin Fremel-owned hut in Pretzsch was taken over by the Electress . Tschirnhaus was entrusted with the management of the Ostrahütte in Dresden and the glassworks in Glücksburg near Wittenberg. As in Dutch and French factories, the system of piece wages was introduced, which replaced the usual time wage .

On the Friedrichstädter Ostrawiese on the Weißeritz he built a grinding and polishing mill, which he equipped with machines he had developed himself. In it the mined gemstones and from 1700 also products of the Electoral Saxon glassworks were processed. In 1706 this mill was demolished on the orders of the governor of Dresden, as a clear field of fire was needed against the advancing Swedes.

Around 1700 Tschirnhaus published another philosophical-pedagogical text for teaching in higher schools. In the Thorough Guide to Useful Sciences , Tschirnhaus again emphasized the importance of a solid education in mathematics and the natural sciences.

1701–1702 trade, lecture and research trip to Paris

Another trip in the winter of 1701 took Tschirnhaus via Holland to Paris. The trip served to sell glass, semi-precious stones and products from the blue color factories of Saxon manufacturers. Tschirnhaus visited faience factories in Delft , whose products were called porceleyne . He made his way to Paris via Manufacture Saint-Cloud Saint-Cloud . The manufacture was founded by Claude Reverend in 1666 and was run by Henri Charles Trou in 1701 . Around 1670 Pierre I. Chicaneau succeeded in producing soft- paste porcelain (frit porcelain) and from 1670 this was used to decorate the Trianon de Porcelaine in Versailles.

Tschirnhaus attended the Académie des Sciences in Paris . Since 1699 it was located in the Louvre as the Académie royale . Due to the financial difficulties after the failed wars of reunion, this institution founded by Colbert was also the subject of administrative reforms. In January 1702, Tschirnhaus publicly justified his scientific work here for the last time.

As in the second edition of Medicina mentis in 1695 , in which he used the study of volcanism as an example to illustrate his method of knowledge, the presentation of the topic of the generatio curvarum per focus in the lecture served to clarify the aspects of his method of the ars inveniendi . For Tschirnhaus, the method had to be distinguished by its clarity and ease of use. The method proposed by Tschirnhaus as an alternative, however, lagged behind the infinitesimal calculus developed by Leibnitz in terms of its universality . On February 5, 1702 Tschirnhaus returned to Electoral Saxony. Four days later he married Elisabeth von der Schulenburg zu Mühlbach.

Excursus: Political and economic situation after 1700

After 1702 the situation in Saxony deteriorated dramatically. The Great Northern War begun by August II against Sweden to reorganize the balance of power in the Baltic Sea region got completely out of hand.

From 1702 the Swedes occupied Polish territory and after the conquest of Thorn the military position of Electoral Saxony was hopeless. Due to the devastating consequences of the war, the Polish nobility split and the Confederation of Warsaw elected Stanislas Leszczynski as the new Polish king in 1704 . Charles XII. secured the choice. After the Saxon-Polish army was destroyed near Frauenstadt on February 3, 1706 , the Swedish army occupied Electoral Saxony. Thereupon the Secret Council signed the peace treaty with Sweden in the Altranstadt Peace . Deprived of all means, August II recognized the contract on December 31, 1706.

To avert the immediate insolvency, Peter I transferred 13,000 rubles to his ally in 1705. The destruction and looting ruined Tschirnhaus and the de facto bankruptcy of Saxony made the reforms begun in 1694 and further research difficult.

1701–1708 porcelain research

1701–1703 The College Contubernium and again glass

Johann Friedrich Böttger had fled from Berlin to Wittenberg in 1701 and was brought to Dresden by August II after an extradition request from King Friedrich I in Prussia . After August II founded the Kollegium Contubernium , the alchemist worked on the production of gold under the supervision of Michael Nehmitz. Tschirnhaus probably first met Böttger, who was inspired by Johann Kunckel, in March 1702.

Apparently Tschirnhaus was also not yet aware of the production of porcelain at this time. To Wilhelm Homberg he was only able to confirm the long-known composition and reports published again in Amsterdam in 1665 by the Dutch ambassador to Madagascar and representatives of the Verenigde Oostindische Compagnie Joan Nieuhof . He had sent Leibniz a requested sample of the porcelain mentioned to him on October 12, 1694.

Apparently Tschirnhaus used the furnaces of the Dresdner Glas Fabrique Neuostra both for the production of glass and for the research and development of new ceramic materials. The glass melting furnaces were not suitable for the production of porcelain because of their lower temperatures. In 1704, the opaque red-brown marbled Tschirnhaus glass was developed here, which was manufactured in larger quantities after 1713 and has color parallels to lacquer work .

1704–1705 Faience and stoneware production

In 1703 Böttger fled to Austria. The subsequent extradition was followed by imprisonment on the Königstein . In 1704 Tschirnhaus and Gottfried Pabst von Ohain were entrusted with the supervision of Böttger's work in Dresden. These were continued in 1705 at the Albrechtsburg in Meißen. The experiments served to invent the porcelain. In 1705 further ceramic products were imitated. The production of brick-red stoneware , jasper porcelain , which became known as Böttger stoneware , was imitated in Delft after 1678 by Ary Jausz de Milde based on the model of Chinese tea stoneware, the Yixing ware. Due to this development, the first faience manufacture for Delft faience products was established in Dresden in 1706 .

1705–1707 porcelain

From this point on, the research continued in three separate laboratories. Böttger stayed in Meißen, while Tschirnhaus worked in the so-called Dresdner Goldhaus , the laboratory for gold production set up for Böttger in the Residenzschloss, and Ohain in the Pragerschen Vorwerk in Freiberg .

One of the results of this work was the improvement of the furnace technology under the direction of Berggrate Gottfried Pabst von Ohain . Tschirnhaus had already started to gradually improve it in its own glassworks in Kieslingswalde in the 1690s. In addition to economic operation, a long service life was essential for technical application. In addition, furnaces that were used for porcelain production had to generate and withstand higher temperatures and enable a uniform and controlled firing process with continuous loading. From 1706, the Freiberg smelters and miners David Köhler, Samuel Stöltzel , Johann Georg Schubert and Paul Wildenstein were involved in this development. The Freiberg stove builders Balthasar Görbig and Andreas Hoppe contributed further knowledge .

This was another step towards the development of the first European hard porcelain . Due to the occupation of Electoral Saxony and the siege of Dresden by Swedish troops, Böttger von Meißen was again taken to Königstein Fortress for a year. After the departure of Charles XII. In the autumn of 1707, the experiments in the vaults of the northern fortifications of Dresden, the Jungfernbastei , were continued in a newly established laboratory. At the end of December 1707, Böttger and Bey Hülffe von Tschirnhaus succeeded for the first time in producing a vessel made of hard- paste porcelain. In the same year, Sophie, Tschirnhaus's second wife, died. By this time the two children who had emerged from the marriage had already died.

In addition to the material composition, knowledge of the sintering process and its safe control was a prerequisite for the production of porcelain. Only then could one think of serial production. August II appointed Tschirnhaus secret councilor and director of the manufactory to be founded and decreed that "we have had 2561 thalers paid out to Herr von Tschirnhausen" . Von Tschirnhaus asked, however, to be allowed to use this title only after production had started.

On October 11, 1708, Ehrenfried Walther von Tschirnhaus died of the consequences of the dysentery in the Fürstenberg House in Dresden. He was buried four days later in the Kieslingswalde church. The funeral ceremony took place on December 28, 1708. Bernard le Bovier de Fontenelle wrote the obituary of the Académie des Sciences and the brother Georg Albrecht von Tschirnhaus erected a plaque on the grave in 1709. In 1710, the Meissen porcelain factory started operations.

The memorial plaque of Ehrenfried Walther von Tschirnhaus had the following wording:

“To the noble and noble man Mr. Ehrenfried Walther von Tschirnhaus hereditary lord on Kieslingswalde and Stoltzenberg, Royal Polish and Electoral Saxon Council, member of the Royal Academy of Paris, the prince of philosophers, natural scientist and mathematician of his time, who six times Belgium for the sake of higher studies , four times through France, one time England, Italy, Sicily and Malta in twelve years of inquisitive travels, discovered the art of finding the truth and taking care of one's health, and was the first to invent extremely large glass lenses to support optics, as well as jaspamethyst and jasper ponyx cut his own machines and what the present will marvel at, the future will admire, who was the first European to invent the method of making transparent porcelain of any color, so that it surpassed the tableware of the Indians in shine and hardness, the knight who, through his services to the Court, the non-profit sciences and the fatherland themselves acquired an immortal name, born on April 10, 1651, died on October 11, 1708, his only, deeply sad brother, Georg Albrecht von Tschirnhaus, heir to Oberschönfeld and Hartlieb, set this monument in piety to the sorely missed brother. "

plant

Attempt to found an academy

The first suggestions for founding an academy are based on the exchange with Spinoza during his studies in Holland. Together with Leibniz, he fought for the establishment of an Academy of Sciences in Saxony. In contrast to Leibniz, who tried to bring all societities together in an academy with a universal orientation, Tschirnhaus favored the mathematical and natural science disciplines. On his estate in Kieslingswalde , Tschirnhaus had a group of employees that was to become the nucleus of the academy. Among them was the Danish mathematician Georg Mohr from 1695 to 1697 .

The founding of a Saxon academy based on the models of the Royal Society founded in London in 1660 and the Académie des sciences de l'Institut de France founded in Paris in 1666 failed. The reasons for this were financial difficulties in the wake of the Great Northern War. Leibnitz, however, succeeded in founding the Electoral Brandenburg Society of Sciences in Berlin in 1700 . This also meant that Tschirnhaus's suggestions fell on fertile ground.

The ars inveniendi as the method of philosophy

As a student of Cartesian rationalism, Tschirnhaus saw the structural science of mathematics and, in it, the branch of general algebra as a means and method of ars inveniendi . In this art of discovery , Tschirnhaus believed to have recognized the true philosophy and through it he promised himself universal gain in knowledge for the other areas of natural science . Already Francis Bacon , the pioneer of empiricism had it in similar form in Novum Organum formulated. Tschirnhaus was looking for a continuation of the rationalism founded by Descartes. It found its way in the synthesis of Bacon's empiricism and Descartes' rationalism .

Tschirnhaus's weakness lay in the imbalance in the valuation of both. The overestimation of the mathematically applied method of knowledge without sufficient empirical knowledge of the causality of all individual factors was the reason that Tschirnhaus repeatedly came to conclusions which he assumed to have found universal solutions in them. Examples of this are the Tschirnhaus transformation , as well as the explanations on the cause of volcanism. Both were not found to be universally generalizable, but were only partially true as a special case or false as a shortened conclusion.

His philosophy was geared towards inventing, which is also reflected in the title of his main work Medicina Mentis, sive Artis Inveniendi praecepta generalia . While avoiding the term philosophy , which he replaced by Medicina , Tschirnhaus combined a philosophy as a practice, the main aim of which should be to serve as an applied science .

The positions he set out in it referred to rules already formulated by Descartes and it can be disputed whether the method, which was written down after 1682 and published in 1686/1687, was developed from his own practical testing or at that time was only a claim by Tschirnhaus.

From the third rule of self-realization of thinking as proprio Marte , everyone on their own initiative, with their own strength and will - without blind repetition of common places ( Loci Communes ), in which Tschirnhaus clearly distinguishes himself from the method of the humanists of the early modern age, he derives his fourth rule.

He insisted on the didactic principle of clarity and a method aimed at simplification. This basic idea also determined the book Thorough Guide to Useful Sciences [...] published in 1700 , which he published at the instigation of Christian Weise and the pietistic educators Philipp Jacob Spener and August Hermann Francke . He was also very popular with Leibniz, whose simpler method of calculus prevailed over Isaac Newton's .

For a long time Tschirnhaus was wrongly not counted among the first line of philosophers of the late Baroque. The exchange between Spinoza, Leibniz, Johann Christoph Sturm and Christian Wolff , in particular, was influenced by his approaches. It was not until the beginning of the 20th century that his philosophical and methodological work was again the subject of research and was treated anew in the writings of Johannes Maria Verweyen and Ernst Cassirer on cognitive problems or on logic by Wilhelm Risse .

mathematics

Acta Eruditorum , 1690

In Paris Tschirnhaus worked with Leibniz, who shortly before had developed the infinitesimal calculus , on problems of geometry and number theory. Shortly afterwards Tschirnhaus discovered a way of solving cubic equations and believed that he had found a universal way to solve equations of the nth degree. This becomes the equation of the nth degree

${\displaystyle \qquad a_{n}x^{n}+a_{n-1}x^{n-1}+\cdots +a_{1}x+a_{0}=0}$

by transformation ( Tschirnhaus transformation ) to a new variable y of the general form

${\displaystyle \qquad y=b_{n-1}x^{n-1}+b_{n-2}x^{n-2}+\cdots +b_{1}x+b_{0}}$

with coefficients

${\displaystyle b_{n-1},b_{n-2},b_{n-3},\ldots ,b_{1},b_{0}\,}$

brought to an equation of the nth degree in y, in which up to three of the next higher power terms can be eliminated by suitable choice . For example, the general equation of the fifth degree can always refer to an equation of the form ${\displaystyle b_{i}}$

${\displaystyle \qquad y^{5}+c_{1}y+c_{0}=0}$

to be brought. Tschirnhaus originally said, wrongly, that every equation of the nth degree corresponds to an equation of the form

${\displaystyle \qquad y^{n}-c=0}$

to be able to transform (which also worked with the cubic equation), and published this despite warnings from Leibniz in the Acta Eruditorum of 1683. Nevertheless, this contribution by Tschirnhaus is one of the most important advances in algebra since the Renaissance.

The Tschirnhausen cube was named after him in 1900. Tschirnhausen was also one of those who in 1697 solved Johann Bernoulli's task to solve the brachistochron problem . The quadratrix Tschirnhaus can serve to square the circle.

optics

The burning mirrors and glasses developed by Tschirnhaus exceeded the previous ones in terms of precision, size and effect. Whether and to what extent his mathematical calculations contributed to the technical improvement in the manufacture of solar furnaces cannot yet be said. He was one of the first to be able to cast and grind lenses with a diameter of about one meter, for which he had his own grinding shop operated by a water mill in his home town of Kieslingswalde. Some of the instruments have been preserved in various museums such as the Mathematical-Physical Salon in the Zwinger in Dresden, the Deutsches Museum in Munich and the Astronomical-Physical Cabinet of the Hessen Kassel Museum Landscape.

Fonts

His main work was the Medicina Mentis (methodology and epistemology). The work, written from 1682 and published in Amsterdam in 1686/87, was sharply attacked by Christian Thomasius due to its close proximity to Spinoza. Further scientific treatises were published in the Leipzig "Acta eruditorum" and in the memoires of the Paris Academy.

• Traité de l'art de polir les verres . After 1676.
• Medicina mentis et corporis . 1st part dedicated to Louis XIV. Amsterdam 1686.
• Medicina mentis . Amsterdam 1687.
• Medicina mentis et corporis . Translation into Dutch by Ameldonck Block, Amsterdam 1687.
• Medicina mentis . Translation into Dutch by A. Block, Amsterdam, 1687. New German translation Barth, Leipzig 1963 by Haussleiter (with biography)
• Medicina Mentis, Sive Artis Inveniedi Praecepta Generalia . J. Thomas Fritsch, Leipzig 1695.
• Medicina Corporis Seu Cogitationes Admodum Probabiles de Conservanda Sanitate . J. Thomas Fritsch, Leipzig 1695, reprint (with Medicina Mentis 1695) Olms, Hildesheim 1964.
  

  Medicina corporis Amsterdam 1686
• Entretiens sur la pluralité des mondes . Collaboration in the publication of the first German edition of the work published by Bernard Le Bovier de Fontenelle in 1686. 1698.
• Faithful court master on academies and trips . Edited by Wolfgang Bernhard von Tschirnhaus. Hanover 1727 ( digitized and full text in the German text archive )

A facsimile edition of the Thorough Guide to Useful Sciences , 4th ed. Frankfurt and Leipzig 1729, appeared in 1967 by Frommann, Stuttgart-Bad Cannstatt (ed. And introduction by E. Winter).

A complete edition of his writings has been published by the Saxon Academy of Sciences since 2000 (editor: E. Knobloch, edited by: Mathias Ullmann ).

reception

At the end of his studies, Tschirnhaus was already working on problems that should serve glass and porcelain production. The construction of instruments served systematic experiments with earths and silicates at high temperatures. The effects achieved in this way were ultimately not sufficient for the high temperatures of the melting processes. Nevertheless, these works show his part in the solution of the arcanum of porcelain manufacture . In addition to the services of other scientists and technicians from different fields, the inventory of Saxon minerals, the possibility of generating high temperatures with burning mirrors and glasses and Tschirnhaus's experience in the technological field of glass production were one of the prerequisites for the invention of porcelain and its production in the operational form the manufactory.

It is disputed whether Tschirnhaus or Johann Friedrich Böttger was the inventor of hard-paste porcelain . Regarding the two opinions Tschirnhaus or Böttger? subsequently a third established itself; Tschirnhaus and Böttger . In addition to the material composition and the reliable mastery of the sintering process , furnace technology was a prerequisite for the production of porcelain. In addition, colors and glazes had to be found in order to produce pieces that could hold their own in competition with the soft-paste porcelain imported from China and Japan . The comparison with the Manufacture royale de porcelaine de Sèvres shows the difficulties in finding the colors necessary for decoration. Only after these tasks had been solved could the economical production of hard porcelain begin in the form of a manufactory. Tschirnhaus played a major role in the invention of porcelain thanks to his many years of research, but his death in the early phase of porcelain research pushed Böttger into the background in the judgment of posterity.

literature

swell

• HStA Dresden, Loc. 489, Acta Allerhand projects and suggestions concerning ao 1702 seqq., Quoted from [1], 71 project and memorial from Tschirnhaus to King August, for the purpose of founding a porcelain factory.
• HStA Dresden, Loc. 1341, decree of November 30, 1707.
• HStA Dresden, Loc. 2097, No. 49, July 14, 1708,
• HStA Dresden, Loc. 976 (Letter from Böttger of October 14, 1708)
• HStA Dresden, Loc. 379/381

Literature on Tschirnhaus

• Ehrenfried Walter von Tschirnhaus (1651–1708) - Experiments with the solar fire . Catalog for the special exhibition in the Mathematisch-Physikalischer Salon in the Dresden Zwinger from April 11 to July 29, 2001. Dresden State Art Collections. ISBN 3-932264-23-1
• Carl Gerhardt (Ed.): Leibniz - Mathematical Works. Volume 4. Hanover 1859 (correspondence with Varignon, Grandi, Wallis, Zendrini, Hermann, Tschirnhaus), reprint Hildesheim, Olms 1971
• Ulrich G. Leinsle:  Ehrenfried Walther von Tschirnhaus. In: Biographisch-Bibliographisches Kirchenlexikon (BBKL). Volume 12, Bautz, Herzberg 1997, ISBN 3-88309-068-9 , Sp. 660-665.
• Otto Liebmann :  Tschirnhaus, Walter von . In: Allgemeine Deutsche Biographie (ADB). Volume 38, Duncker & Humblot, Leipzig 1894, pp. 722-724.
• Peter Georg Mohrenthal: Life description of the world-famous Ehrenfried Walther von Tschirnhaus in the same message of his writings and rare inventions . In: Curiosa Saxonica , third repository sample 38 u. 39. Verlag PG Mohrenthal, Dresden 1731, pp. 18 and 4
• Günter Mühlpfordt: Ehrenfried Walther von Tschirnhaus (1651–1708) - on his 300th birthday on October 11, 2008. Leipziger Universitätsverlag, Leipzig 2008, ISBN 978-3-86583-275-7 ( preview in Google book search)
• Johannes Verweyen, Ehrenfried Walter von Tschirnhaus as a philosopher. A philosophical-historical treatise . Hanstein, Bonn 1905
• Eduard Winter, Nikolai Figurovskij (Ed.): Ehrenfried Walther von Tschirnhaus and the Early Enlightenment in Central and Eastern Europe. Lectures in honor of the 250th anniversary of death (October 11, 1708). Sources and studies on the history of Eastern Europe; Volume 7. Akademie-Verlag, Berlin 1960, p. 69. (quoted from: Royal Resolution on Böttger's Invoices , 1708, H.St.A. Dresden).
• Siegfried Wollgast: EW von Tschirnhaus and the German Early Enlightenment . Meeting reports of the Saxon Academy of Sciences, Volume 128. 1988
• Rudolph Zaunick: EW von Tschirnhaus . Hellerau Verlag, Dresden 2001
• Hans-Joachim Böttcher: Ehrenfried Walther von Tschirnhaus - the admired, fought and hushed genius . Dresden 2014. ISBN 978-3-941757-42-4

Literature on the invention of porcelain

• Rudolf Forberger : From Böttger's artistically designed hard-paste porcelain to technical porcelain in the 19th century . Meeting reports of the Saxon Academy of Sciences in Leipzig. Philosophical-historical class, Volume 125, Issue 4. Akademie-Verlag, Berlin 1985.
• Royal Library of Hanover, correspondence between Leibniz and Tschirnhaus, sheet 103-107, February 27, 1694, quoted from C. Reinhardt: Tschirnhaus oder Böttger? A documented history of the invention of Meissen porcelain . In: New Lusatian Magazine . Volume 88, 1912, p. 19
• Günter Meier: Porcelain from the Meissen manufactory . Henschelverlag, Berlin 1991, p. 175.
• Curt Reinhardt: Tschirnhausen's research laboratory for porcelain in Dresden . In: New Lusatian Magazine. Volume 105, 1929, pp. 142, 149. (Th. Hempel: Böttger . In: Johann Samuelansch , Johann Gottfried Gruber (Ed.): General Encyclopedia of Sciences and Arts . 11th part, Leipzig 1823, p. 289– 293, quoted from Curt Reinhardt)
• Otto Walcha; Helmut Reibig (ed.): Meissner porcelain. From the beginning to the present. Verlag der Kunst, Dresden 1973.

Other literature used

• Carlo M. Cipolla: The Diffusion of Innovations in Early Modern Europe . In: Comparative Studies in Society and History. Volume 14, No. 1, January 1972, pp. 46-52. Society for Comparative Studies in Society and History Published by Cambridge University Press.
• Norbert Elias : The courtly society . Studies on the sociology of royalty and the court aristocracy with an introduction: sociology and history . Luchterhand, Neuwied / Berlin 1969
• Rudolf Forberger: The manufacture in Saxony from the end of the 16th to the beginning of the 19th century . German Academy of Sciences in Berlin, writings of the Institute for History. Series I: General and German History. Volume 3. Akademie-Verlag, Berlin 1958.

Web links

Commons : Ehrenfried Walther von Tschirnhaus  - album with pictures, videos and audio files

• Ehrenfried Walther von Tschirnhaus in the Mathematics Genealogy Project (English)

General

• Website of the Tschirnhausgesellschaft .
• Pictures from Sławnikowice - Kieslingswalde in the Lower Silesian Voivodeship .
• Spektrum .de: Ehrenfried Walter Graf von Tschirnhaus (1651–1708) April 1, 2016

literature

• Literature by and about Ehrenfried Walther von Tschirnhaus in the catalog of the German National Library
• Literature by and about Ehrenfried Walther von Tschirnhaus in the Saxon Bibliography
• Publications by and about Ehrenfried Walther von Tschirnhaus in VD 17 .

volcanology

• Gunter E. Grimm: reasoning and writing strategy. On the volcanism discourse in the work of Ehrenfried Walther von Tschirnhaus . (PDF; 154 kB)

Individual evidence

1. ↑ Forberger, 1985, pp. 13-16.
2. ↑ see the website John Collins and James Gregory discuss Tschirnhaus of the University of St. Andrews , accessed December 21, 2015
3. ↑ Eike Christian Hirsch: The famous Herr Leibniz . Becksche Reihe, p. 80. The often very critical Pell, however, had publicly exposed the young inexperienced Leibniz during his visit in 1673.
4. ↑ The Museum of Manfredo Settal - Settalas Museum in Milan
5. ^ Adolf Hantzsch: The mirror loop near Dresden ; Dresden 1883; ( Digitized version ) page 40