sciences and LEARNED books
persian medicine before avicenna
Since ancient times, the scientists were also compilers. The sum of their knowledge was recorded in large encyclopedic volumes in which the author inserted his own discoveries.
Abul-Hasan al-Tabari was a physician who specialized in diseases of skin and eyes in western Persia at the time of the Buyid dynasty about 1050 years ago. He should not be confused with the famous scholar al-Tabari who had also some interest in medicine.
On April 22 in London, Sotheby's sells a manuscript of the last two chapters, IX and X, of the medical book by Abul-Hasan al-Tabari, lot 68 estimated £ 220K. This important fragment contains about 250 leaves 19 x 16 cm with 18 lines per page in a beautiful Arabic angular script.
The book closely follows the teaching of Hippocrates whose name is mentioned in the title. The chapters of the manuscript for sale are devoted to stomach and liver, with their normal and abnormal behaviors and the treatments.
The formula 'rahmat Allah alayhi' after al-Tabari's name indicates that he was deceased, probably shortly before. This ancient manuscript written about 1000 years ago is contemporary of the early career of Ibn Sina (Avicenna) who will be the most outstanding Persian philosopher-doctor of the Middle Ages.
13th Century CE Elements and Almagest
2018 SOLD for £ 320K including premium
The exceptional clarity and irrefutable logic of the Elements by Euclid have created an everlasting masterpiece of scientific and educational literature. His personal input is certainly very important but could not be identified. Mathematike Syntaxis by Ptolemy is different because the author himself has constructed a planetary model by associating geometric considerations with the apparent motions of planets.
The achievement of antiquity would have been lost forever in medieval times if they had not interested the Arabs. These texts are translated and are the subject of many manuscripts in complete or abridged form, often with comments. Different translations are also prepared after further readings of the surviving texts. Real handwritten editions are done.
Commissioned by the Caliphs, great authors are thus reviving the ancient fundamental treatises. Euclid and Ptolemy were both reworked by al-Hajjaj, Ishaq ibn Hunayn and Thabit ibn Qurra. The book of Ptolemy takes the Arabizing title under which it is still designated now, the Almagest.
On April 25 in London, Sotheby's sells two Arabic manuscripts of the 7th century AH, estimated £ 200K each.
Lot 30 is an edited version of Euclid's Elements, with drawings of the figures and many comments. An Egyptian origin is announced as probable. The age of the paper is confirmed by carbon analysis.
Lot 31 is an abridgment of the Almagest, made in Persia and dated 671 AH corresponding to 1272 CE. The scientific reasoning with its illustrations is complete and complies with Ptolemy's approach but the text has been simplified, perhaps for pedagogical reasons. No other example of this specific abridged text is known.
On April 26 in London, Christie's sells a compilation of five treatises on astronomy and mathematics including the Almagest. This manuscript is a copy made in Anatolia in 678 AH corresponding to 1279 CE from an original text by al-Tusi who had died five years before. It is estimated £ 300K, lot 36.
Euclid at Sotheby's : SOLD for £ 320K including premium
Almagest at Sotheby's : unsold
Compendium at Christie's : unsold
1542 the book of herbs
Medicine doctor and humanist, Leonhart Fuchs works since 1533 at the University of Tübingen where he creates a garden of medical botany. He relies on the descriptions of plants by Hippocrates, Dioscorides and Galen and is the first botanist to understand the interest of realistic illustrations.
Fuchs publishes in 1542 De historia stirpium commentarii insignes, a folio 36 x 24 cm printed in Basel. This 896-page book includes no less than 508 full-sized illustrations of plants.
It is a team work : the portrait of the author in full length occupies a page and his three collaborators share together another page where their names are identified. The two painters (pictores operis) are busy drawing a potted plant. The third artist is the sculptor responsible for preparing the xylography blocks.
Of course the book was conceived to be colored. A copy of the first edition was put in color in 1552 by an artist named Hubert Cailleau who had the very good practice of signing and dating his works. Cailleau worked in Valenciennes in the tradition of the illuminators and was at that time a specialist of the illustrations of manuscript books of music and mass songs named antiphonaries and graduals.
This exceptional copy is estimated € 400K for sale by Reiss und Sohn in Königstein im Taunus on October 30, lot 592. Here is the link to the website of the auction house.
1543 The Functions of the Human Body
2012 SOLD 122 K$ including premium
Andries van Wesel, who latinized his name in Andreas Vesalius, was one of the founders of modern science and one of the scientists whose work had the greatest impact on our civilization. He is the explorer of the human body.
Born into a family of doctors, he observed the decomposed corpses on the gibbet of Brussels, in front of his home. He early appreciated that only direct observation could lead to understanding.
Not only he refuted all the errors of Galen which prevented the progress of medicine and surgery, but also he showedthe reason: in order not to defy the taboos of the Roman Empire, Galen had dissected monkeys. I give only one example among so many, but it is spectacular: analyzing breathing, Vesalius paves the way for life saving ventilation.
His drawings are plagiarized and challenged. Vesalius therefore decides that he must collect his observations andfigures in a masterly work. After four years of preparation, De Humani Corporis is published in Basel in 1543. The prints are so beautiful that they are considered to have been made by one of the best artists of that time.
Vesalius wanted to convince. One of the pages, known as Charta Parvas, includes eight figures of organs that the reader is invited to cut off for repositioning the image in the body. Many have followed these instructions, and very few copies have kept this page intact.
One of them, complete with its 663 pages in folio format 43 x 28 cm, is estimated $ 150K, for sale by Heritage in Beverly Hills on October 4. Here is the link to the catalog.
POST SALE COMMENT
The price, $ 100K before fees, $ 122K including premium, remained below the lower estimate (positioned at $ 120K on LiveAuctioneers).
1609 the man who measured the skies
2015 sold for £ 146k including premium
Kepler understood that the heliocentric model of Copernicus was not enough. The demonstration proposed by Copernicus is admirable but is indeed nothing more than a calculation.
Kepler had a poor eyesight and was not himself an astronomer. He joined the team of Tycho Brahe in Prague. Kepler used the highly accurate observations made by Brahe while opposing his planetary system that did not explain the orbit of Mars. His own work led him to demonstrate that the orbit of a planet is not circular but elliptical.
He now sees the sun as a motor that generates a greater speed when the planet is closer and compares this effect to a magnet. Newton will rely directly on Kepler's results to formulate the law of universal gravitation.
Kepler prepares from 1600 to 1606 the presentation of his first two laws. A dispute with Brahe's heirs suspends the publication until 1609. The title, Astronomia nova, shows Kepler's rightful ambition to offer a completely new approach in this domain. Astrophysics was indeed born with this book.
The printed quantity is very small : the author is an employee of the Emperor Rudolph II and the edition is done without a commercial intent. To compensate for some salary delays, Kepler obtains the right to sell a few copies.
A copy of Astronomia Nova which belonged to the Royal Institution of Great Britain is estimated £ 90K for sale by Christie's in London on December 1, lot 245.
Here are two recent results on other copies : £ 212K including premium by Sotheby's on May 20, 2014, and $ 230K including premium by Christie's on June 17, 2008.
1610 galileo watches the truth
2016 sold for £ 315k including premium
Everything remains to be done in his field and his achievements are frequent and numerous. In 1597 Galileo turns the compass into an instrument for the quantitative analysis of many geometric figures, for the purpose of military applications. He self publishes this promising invention in 1606. He replies in the following year by another book to Baldassare Capra who had accused him of plagiarism.
A copy of these scarce little books bound as a single volume is estimated £ 250K for sale by Christie's in London on July 13,lot 40.
Galileo had previously understood that meticulous observations of the sky can improve the modeling of physical phenomena. In 1604 his observation of a nova provides a first exception to Aristotle's doctrine of the immutability of the heavens, considered as an untouchable truth by the Church.
The greatest scientific advance made by Galileo comes in 1609 when a friend informs him of the realization of a longue-vue (spyglass) by Lippershey. Galileo desires to watch the sky with the method of this Dutch opticist. After a frenetic phase of trial and error, Galileo gets a satisfactory instrument.
The sky seen by Galileo with his telescope is very different from its traditional modeling. Within weeks the scientist discovers the complex texture of the Milky Way, the roughness of the surface of the Moon and the satellites of Jupiter. With this new information, astrology is suddenly losing its meaning.
He must act quickly to avoid falling again in anticipation quarrels. Galileo publishes his book Sidereus Nuncius (Sidereal Messenger) in Venice in March 1610. This is too much for the traditionalists. Galileo had been careful to hide the heliocentric hypothesis but his book definitively refutes the Ptolemaic system. Religious persecution will now begin but Galileo knows that his observations and their consequences are scientifically irrefutable.
A first issue of the Sidereus Nuncius is estimated £ 200K by Christie's in the same sale as above, lot 41.
RESULTS INCLUDING PREMIUM :
Compass (lot 40) : £ 240K
Astronomy (lot 41) : £ 315K
1613 Champlain tells his Travels
2009 SOLD 760 K$ including premium
Outstanding explorer and cartographer, strong agent of French colonization, Champlain was also a naturalist and scientist. Ethnographer, he watched the natives of North America with sympathy. The success of his endeavours is astonishing: he never ceased to travel, did not lose a single boat, and his greatest claim to fame is the founding of Quebec City.
"Les Voyages", published in Paris in 1613, is the journal of his explorations, with many illustrations and detailed maps. A copy is for sale on December 3 by Bloomsbury in New York. Its estimate at $ 250 K is reasonable if one considers that it fetched $ 360 K in a previous sale at Sotheby's in May 1999, according to information found in the catalog.
LiveAuctioneers provides the online support for the auction, and shares the description of the lot and an illustration.
POST SALE COMMENT
It is logical that this book was sold well above the price of the map sold last year by Sotheby's. At 660 K $ excl., it is an excellent result.
1638 THE METHOD OF DESCARTES
When Descartes rediscovered the optical refraction, he also understood that geometry, of which he had been one of the most famous conceivers, could not explain everything. Encouraged to seek the true nature of the world, of the individual and of himself, he endeavoured to develop a metaphysical approach to describe the phenomena of physics.
In 1637, his Discours de la Méthode has the effect of a bomb in the learned community. Becoming a universal thinker like Aristotle before him, he hopes that his metaphysical system may be strong enough to establish irrefutable laws of morality.
The great minds of his time try to understand him, and Descartes improves his system by answering their arguments.
His letter to Mersenne dated May 27, 1638 is an organized response to no less than 17 questions. Some arguments are issued for the promotion of a modern scientific demonstration, for example when he says that no one disputes the qualification of scientist commonly attributed to Archimedes although he was not a geometer.
This autograph letter of four pages in a tight writing had belonged to the Institut de France but was among the documents stolen by Libri before 1847. Considered as lost, it was recently rediscovered. It is estimated CHF 250K, for sale by Koller in Zürich on March 29.
1680 new flowers for the butterflies
She is interested in insects since childhood. She reconstitutes the cycle of metamorphosis (egg, caterpillar, pupa, butterfly) probably even before Redi publishes the decisive arguments against the spontaneous generation.
Not only the insect is not a creature of the devil, but it is useful. Curiosity towards the Far East had been maintained by De Bry, publisher of images from grand voyages. Europe seeks to imitate the silk culture with local solutions, and Maria Sibylla is one of the first scientists to study the relationship between plants and their pests.
In 1612, De Bry had published a florilegium, twice reissued by his son-in-law. This wording designated the collections of pictures of flowers used as patterns by the embroiderers. For her illustrations, Maria Sibylla Merian reuses the format developed from 1643 by Nicolas Robert in booklets of twelve images each.
From 1677 to 1683, she publishes five booklets, three on flowers and two on caterpillars. In 1680, her husband Johann Andreas Graff publishes a book gathering her 36 flower images, 30 x 19 cm, under the title Neues Blumenbuch. A complete copy colored by hand is estimated £ 200K for sale by Christie's in London on July 15, lot 150.
The three fascicules for the Blumenbuch in their first edition were sold as a single lot for £ 560K including premium by Christie's on 8 June 2011 over a lower estimate of £ 60K.
Shortly before her death in 1717, Maria Sibylla added a third booklet on the caterpillars and their metamorphoses which was immediately collected with the previous two for a Dutch edition. A copy of this book was sold for £ 193K including premium by Christie's on November 23, 2011.
1687 The Explanation of the Universal Laws
2013 SOLD 340 K£ including premium
Astronomy and mathematics are inseparable in the history of science. Showing through the accuracy of his calculations that the Ptolemaic system could not explain all the movements of the planets, Copernicus opened the way to modern science, soon followed by the physicists Galileo and Kepler.
In science, unification is stronger than diversification. Developing new techniques of algebra, Isaac Newton was able to assess that the law of gravitation is universal, meaning that it applies altogether to terrestrial and astronomical phenomena.
The Royal Society had actively supported the discoveries of Newton, known as one of the best mathematicians of his time. The Secretary Edmond Halley had directed his research and the President Samuel Pepys provided his imprimatur in 1686.
The book is printed in Latin in 1687 for the Royal Society, in quarto format 24 x 18 cm, entitled Philosophiae Naturalis Principia Mathematica.
A copy in very good condition of the first issue of the first edition in a vellum binding of that time is estimated £ 250K, for sale by Sotheby's in London on November 27. Here is the link to the catalog.
POST SALE COMMENT
This very good copy from a great issue was sold for £ 340K including premium.
1745-1752 The Anatomical Defoliations of Gautier d'Agoty
2008 SOLD 70 K€ before fees
Jacques Gautier d'Agoty was of the same generation as the French Encyclopédistes, and like them he was a man of technology and culture. He was a pupil of the German engraver Le Blon, who had invented a printing process using the three colors blue, yellow and red. Gautier d'Agoty added the black. The quadrichromy of today is based on the same colors.
His plates of anatomy are particularly important. For the texts of his books, he reused the work of a doctor of the previous century named Joseph-Guichard Duverney.
The lot 1362 from the sale of Reiss in Koenigstein of 28 and 29 October, estimated 75 K€, is a single bound volume of three anatomy books of Gautier d'Agoty, printed between 1745 and 1752, including a total of 46 of these precious prints, successively on the brain, viscera and head. Gautier endeavoured to represent the subjects in life size and color.
The prints show successively the same subject from where has been removed the upper layer visible in the foreground on the previous image. This display of a very modern logic had to be viewed as exceptional by readers in the eighteenth century, when so many scientific works were still characterized by confusion.
In leafing through dictionaries and encyclopedias of today, it is very difficult to find such well-deserved tribute that should be attributable to this pioneer. Thank you to the auction house Reiss to have revisited Gautier d'Agoty, a true follower of Vesalius.
POST SALE COMMENT
This book was sold 70 K€ before fees, just below the estimate. It is a good result.
1761-1775 the book of 26,000 plants
2016 sold for € 75K including premium
It is listed again by Ketterer Kunst to be sold in Hamburg on May 23, lot 27 estimated € 60K. The comparison of the condition makes it obvious that it is the same copy. A page is illustrated on Artdaily. I discussed this lot as follows in 2011.
The knowledge and classification of nature represent a major scientific progress of the eighteenth century. It is rightly associated with Linnaeus who developed the concepts still used today of genera and species.
Monumental editions, often spanning over many years, were illustrating with art and accuracy such systematic researches. For example, the Histoire Naturelle by Buffon, who did not follow the theories of Linnaeus, lasted from 1744 to 1804, thus ending 16 years after the death of its initiator.
In London, The Vegetable System authored by John Hill is another monument in the publishing history of that century. In 26 sections published between 1761 and 1775, the author unfolds a comprehensive description of the life and anatomy of no less than 26,000 plants. From the second volume, he uses the scientific names given to them by Linnaeus.
John Hill had been a great scientist but his personal behavior estranged him from his contemporaries and his name fell into oblivion.
1776 ENLIGHTENMENT AND WEALTH IN SCOTLAND
2013 SOLD 46 K£ BEFORE FEES
During the Enlightenment, Scotland produced very brilliant thinkers. Close to Hume, Adam Smith explores the relationship between morality and logic, for the purpose that human societies find the engine of their growth.
Considering the group as a set of positive interactions between individuals, he includes in his analysis the commercial transactions, which should bring benefit to both the seller and the buyer.
Published in 1776 in London, An inquiry into the Nature and Causes of the Wealth of Nations is the result of ten years of research by this former professor. A copy of the first edition, in two volumes 27 x 22 cm, is estimated £ 30K, for sale by Lyon and Turnbull in Edinburgh on September 4.
This work of a philosopher is highly important in the history of our societies. Smith had shown that people could trade together, each one with his own criteria and strategies, without creating damage to the whole. By this act of creationof the economic liberalism, he pushes humanism to an extreme positive but not utopian vision.
The political impact is just as important because the role of a central government is reduced. Smith's text is logical and peaceful, but it is not a coincidence that the violent pamphlet from another British, Thomas Paine, was publishedon the same year, ruining forever royalism in the future United States of North America.
POST SALE COMMENTS
Very good price, £ 46K before fees, just shy to the higher estimate, for this first edition of an outstanding text.
1802-1816 Lilies in the Royal Gardens
Introduced to Versailles, Redouté entered the service of Queen Marie-Antoinette. He will be under the Empire an official artist of Empress Joséphine and will provide the artistic training for princess Adelaïde d'Orléans.
Redouté painted on vellum several hundred watercolors showing the flowers of the gardens of Malmaison, Saint-Cloud, Versailles and Sèvres. His botanical accuracy is extreme, without error of proportions and without distortions.
Redouté prepares the engravings associated with his watercolors. To obtain the desired precision of the contrasts the plates are re-inked after each individual impression. The images are finished in watercolor guided by tiny dots engraved in the sheet.
This set of 487 images 51 x 34 cm is printed in 280 copies by Didot jeune and provided in 80 parts between 1802 and 1816. The title, Les Liliacées, is reducing compared to the content which covers all the monocotyledons.
The young duchesse de Berry belonging by her marriage to the Legitimist branch of the Bourbons will become in her turn a protector of Redouté. Before the fall of the regime she owned the original watercolors of the Roses published by Redouté after the completion of the Liliaceae.
On July 11 in London, Christie's sells a copy of Les Liliacées that had belonged to the duchesse de Berry. Bound for the duchesse in eight volumes, this set is estimated £ 350K, lot 281.
In 1985 the original watercolors of the Liliaceae bound in 16 volumes were sold in a single lot by Sotheby's for $ 5.5M including premium. This remarkable result was at that time the tenth highest price recorded in an art auction. Purchased by a bookseller for a syndicate created by him for this operation, they were distributed just after the sale among his share holders, resulting for his benefit in the dismantling that had originally been planned by the auction house.
The sun’s out, flowers are in full bloom, check out the most luxurious and spectacular botanical books ever published: Redoute’s Lilacees on #PublicView now in #London, ahead of our Valuable Books and Manuscripts sale on Wednesday https://t.co/6RPJrfnatP #ClassicWeek pic.twitter.com/cEi13xpAFP— Christie's (@ChristiesInc) July 7, 2018
1838-1844 WHEN THE INDIAN CHIEFS VISITED WASHINGTON DC
2010 SOLD 77 K$ INCLUDING PREMIUM
The genesis of one of the finest illustrated American books of the early nineteenth century is told in the catalog fromHeritage Auction Galleries.
The Indians could not ignore the central government, and vice versa. Urged by this mutual curiosity, American officials took an interesting initiative from 1824: they had painted the portraits of their most distinguished Indian visitors.
It was attempting to publish these documents. Fortunately, the lithography facilitated this type of project. From 1837 to 1843, the superintendent of Indian affairs at the War Department, Thomas L. McKenney, had engraved 120 portraits in folio format (51 x 36 cm). These images were compiled in a book in three volumes (dated 1838, 1842 and 1844) entitled "History of the Indian Tribes of North America, with Biographical Sketches and Anecdotes of the Principal Chiefs," with text by James Hall.
According to the custom of the time for the illustrated books of high quality, many copies were colored by hand. This applies to the copy for sale on February 11 in Beverly Hills. Estimated $ 100K, it is from the first edition. The first two volumes are in the second issue, the last one is in the first issue.
The original paintings were destroyed by fire in 1865.
POST SALE COMMENT
This prestigious book was sold $ 77 K including premium, far below the estimate, perhaps because the first two volumes were not from the first print. It is a very good deal for the buyer.
1843 The Bygone Cultures of North America
In 1803 Meriwether Lewis had traveled Missouri on a mission for President Jefferson who had just bought the Louisiane from Napoléon. For his second major exploration, Wied-Neuwied chooses this region. The Plains are populated by semi-nomadic tribes whose lives have already been altered by the fur trade.
Wied-Neuwied wants to compare the Indian tribes of North America to those of Brazil. He hires Karl Bodmer to illustrate his trip. In the spring of 1833, the indispensable collection of reptiles and amphibians is completed. Wied-Neuwied and Bodmer then travel up the Missouri river by steam and then by keelboat to Montana, spend the winter of 1833-1834 in Dakota and return to St. Louis in May 1834.
Wied-Neuwied is in no rush to publish his findings and the preparation of his book is extremely careful. Bodmer makes from his sketches 81 wood engravings, 61 x 46 cm including the margins, which will form a separate volume. The printing of the plates is carried out in Paris. Some copies are hand colored, generally for about thirty selected images, very rarely for the whole. Two versions exist, edited in German from 1839 to 1841 and in French from 1840 to 1843.
An English edition is prepared in 1843 with a simplified text, using copies still available from the original plate printing which are hand colored in London. The translator comments that several tribes surveyed in the work were depleted by smallpox in 1837 : the work of Wied-Neuwied and Bodmer is already the testimony of a bygone past.
A wholly colored copy of this book titled Travels in the Interior of North America is estimated $ 400K for sale by Sotheby's in New York on October 15, lot 22.
1866 peas in the garden
2016 sold for £ 240K including premium
The young man's dream for training materializes in 1851 when he studies at the University of Vienna. He is interested in the use of mathematics. This son of peasants chooses to study hybridization of animals and plants without abandoning meteorology which was the passion of his life.
His superiors do not appreciate his observations on mice mating. He now selects a plant. Peas have differentiated characters which are easy to identify. From 1854 to 1863 Gregor Mendel performs the statistical analysis of seven characteristics observed on 28,000 peas in the garden of the monastery.
The choice was suitable. The proportion of the two colors was 3 to 1 in the population of these plants but the hybridization between two different colors provides a homogeneous population in the first generation. Mendel guesses that an invisible factor makes dominant one of the colors. Recombination leads to a return to the normal proportion from the next generation.
In 1861 Mendel was a founder of the Natural History Society in Brünn. He explains his results in two lectures in 1865. The Society publishes his report in 1866 in 47 pages in its proceedings which are distributed to 134 scientific institutions. 40 offprints are provided to the author in the usual tradition for scientific communications. Mendel uses them. Only one addressee responds : he has some doubts.
Elected superior of the monastery in 1868, Mendel is now overloaded. His 1865 lectures remain the only testimony to his invention of the new science of genetics. His work will remain unnoticed until 1900 and the original versions of the report are therefore extremely rare in private hands. An offprint is estimated £ 200K for sale by Christie's in London on July 13, lot 177.
1880 discussion on the origin of man
2015 sold for $ 197K including premium
In this book, the scientist carefully avoids to comment on the application to man of the mechanism of natural selection. Theologians are not misled. Their reactions will be passionate.
Charles Kingsley is the first clergyman to openly support Darwin. He states four days before the publication of the book that the evolution of species is a dogma just as honorable as that of their simultaneous creation. Darwin waits until 1871 to publish a big scholarly book titled The Descent of Man, now displaying his arguments regarding the full application of his theory to the human species.
Darwin was evasive about his faith, not wanting to get involved into religious quarrels. He was certainly very solicited by believers of all kinds, but by his silence he was able to preserve his privacy.
In November 1880 he received a letter from an individual who asked him to take a position on the New Testament while considering that he will cheerfully welcome a similar opinion as Kingsley's. He promises to Darwin that his answer will not be published.
The scientist decides to reply, perhaps because he was annoyed by a political controversy running at that time concerning the ban on an atheist to sit in parliament. In a few words, his statement is crystal clear. He does not believe that the Bible is a divine revelation and therefore that Jesus Christ is the son of God.
The addressee fulfilled his promise and this letter unique in its kind remained secret for over a century. It is estimated $ 70K for sale by Bonhams in New York on September 21, lot 39.
1942 Alan Turing, Theoretician of Logic
2015 SOLD for $ 1.02M including premium
He was a visionary in artificial intelligence at the time when the first modern computers were developed around John von Neumann. During the war, working on the logic of algorithms, he broke the encryption of German Enigma machines previously considered as inviolable.
On April 13 in New York, Bonhams sells a highly rare notebook, lot 1. The scientific thoughts by Turing, written after 1942, are laid at the start and end of the book, while the intermediate pages were used for personal notes by his eminent student Robin Gandy after the ignominious death of Turing (who was pardoned posthumously in 2013 by Queen Elizabeth II).
Both autographs by Turing are unpublished developments. They bring a new vision on the thinking process of one of the most profound scientists of our time, who found through a method of enforcing simplifications the solutions of problems that his illustrious predecessors had just managed to define.
The first of them is a review of Peano's axioms concerning the completeness and consistency of mathematics. After Hilbert, Turing also addresses the third problem of Peano on decidability, meaning the possibility of establishing an algorithm to decide whether a mathematical proposition is true or false. This text is anticipating his involvement with Enigma but certainly helps to understand the thinking process that enabled the deciphering.
The second scientific text of the book is a study of the role of the mathematical notation. Turing appreciated that a complex formulation makes it more difficult to find the solution. His approach is based on the search for a universal language of mathematics by Leibniz. Such researches make him a precursor of computer programming.