Rome Through the Middle Ages

1. Rome Through the Middle Ages

2. Beginning in the Roman Era, circa 30 BCE – 475 AD • Celestial Problems to be solved • Daily motion of fixed stars • Motion of the planets against the stars • Aristotle: • All celestial motion is constant • All celestial motion is circular

3. Ptolemy’s Problems, circa 100AD • Changes in planetary brightness • How stars can move so fast and not fall apart • Which is closer to Earth, Venus or Mercury • Can these phenomena be put into a coherent system?

4. Ptolemy’s epicycles, deferents, and equants were an attempt to solve these problems • But to account for retrograde motion, Ptolemy had to have non-constant motion, violating Aristotle’s physics

5. Ptolemy’s Estimates of the Distances from the Sun* to the Planets in Earth radii *Adapted to represent a Sun-centered universe

6. These problems were not resolved for almost 1500 years • Not many Roman astronomers • Most work done up until 1500 was: • more accurate mapping of the sky with instruments • preserving and translating the knowledge of the Greeks, difficult because much was lost during the Dark Ages

7. Remember: • The Museum at Alexandria contained over 400,000 scrolls • Center of learning for hundreds of years • Burned by zealots in 415 AD • Librarian and Philosopher Hypatia killed by zealots for heresy

8. The Preservers • Boethius (480-524) • Roman of noble birth (but after the fall of the Western Empire) • preserved knowledge of logic and mathematics • translated Aristotle's Logic; Pythagoras; Euclid • Cassiodorus (488-575) • Roman statesman and scholar • wrote commentaries on liberal arts (Quadrivium) • supported making copies of secular works

9. The Irish • The only European region to accept Christianity peacefully • St. Patrick • No violent martyrdom available: Green martyrdom (hermitage) • Gregarious Irish failed at being hermits, so became industrious scribes • Agnostic about what they scribed • Found the continental self-censorship of pagan Greek, Roman, and Hebrew texts silly Skellig Michael

10. Monastary Schools • Acolytes came from all over Europe to study and copy with the Irish • Became experts in ancient languages without prejudice • “Irish miniscule” became the accepted font for European scribes • Modern books are portrait style because Irish sheepskin came in that shape (2 facing pages) • Bede himself noted the industriousness of the Irish in his journal

11. Bede (BEE-dee) (673-735 *the 6940 day cycle when the solar and lunar cycles sync up • English monk, Jarrow, England • By the 7th century only monks were literate • Complied 5 volume history of England from Caesar to 8th C. • made methodical study of tides and published tables • 250 book collection—biggest in England • influenced by Pliny's Natural History • In his Divisions of Time he combined the Greek *Metonic calendar with the Roman leap year to accurately predict Easter many years in advance.

12. Charlemagne (Charles the Great) Grandson of Charles the Hammer Martel who had protected France from the Moors Crowned Holy Roman Emperor in 800AD Empire* included France, the Netherlands, Germany, Poland, Austria, and most of Italy Died 814, the year Viking berserkers invaded Europe and destroyed a lot of the progress towards literacy *Modern names

13. Charlemagne’s schools served a similar purpose to monastery schools, but were directed to include instruction in secular as well as sacred subjects -- reading, writing, speaking, mathematics, natural philosophy • These schools were unable to meet the growing needs of an increasingly secular society • Especially after the Vikings arrived • Some failed, but others like Paris began to assume the modern form of a university

14. The Rediscoverers • Dissemination of Greek Knowledge • The Bactrians: • For centuries after the dissolution of Alexander's empire, Greek culture continued to influence the people of Bactria. Cities like Bactra and Merv were crossroads on the Silk Road that helped introduce new commodities and technologies from the East, such as paper and paper-making circa 750 AD. • Traders traveling the Silk road would return ancient knowledge to the West

16. The Nestorians • Leaders in the early Christian Church* gathered in what they called "ecumenical councils“, meetings at which bishops from all of Christendom could consider, discuss and hopefully come to concurrence on disputed or unclear points of scripture and church doctrine. • At the third council, held in Ephesus in 431 AD, delegates condemned the bishop of Constantinople, Nestorius (381-451), as a heretic for questioning Mary's status as Mother of God… *Eastern Empire: Western Empire in chaos

17. …Nestorius and his followers were exiled to Persia and settled in Edessa.  • Religious conflicts in Edessa prompted the Nestorians to move further east in 457. • Academies modeled after the ancient one in Alexandria were founded in Antioch and Nisibis. • When Islam arrived in the 7th century this Greek tradition would be rediscovered

18. India • Alexander's empire had extended to the Indus River valley, itself a thriving civilization, and communication and trade continued over the centuries via land and sea • Astronomical records from Alexandria found their way to observatories like those in Pataliputra (Patna today) and Ujjain (oo-JEN)

19. Really Nothing Indian astronomers added their own observations to those extant but replaced the Babylonian sexigesimal system with a decimal system that included a symbol for "nothing" to help keep track of place values.  This symbol was called sunya, the Hindi word meaning "the void."  When this was translated into Arabic, scholars used the word sifr, meaning "empty."  Italians transliterated this word as zefirum, zefiro, and zefro, which eventually became zero.

20. Islam

21. In conquering the lands from India to the Atlantic, the Islamic empire fostered a blooming of Greek knowledge and thought • Some of this rediscovered academia found its way west through trade or conquest of the Iberian Peninsula, Al Andalus • When Toledo was conquered by Christians in 1085 this ancient knowledge found its way to Europe

22. Islamic Contributors • Al-Khwarizmic. 800-847 Baghdad • Mathematician; the word algorithm comes from his name • wrote a zij, a publication based on the Handy Tables of Ptolemy • Alhazen 1000 Cairo • Configuration of the World was a realization of the Ptolemaic model later referenced by Georg Peurbach • treatise on optics became widely circulated in Europe, led in part to the invention of spectacles ~ 1300 • Averroes 1126-1198 Cordova (Al Andalus) • philosopher • translated Aristotle , became known as The Commentator • compiled works of Galen • predicted the existence of a new world beyond the Atlantic Ocean

23. New Name for an Old Book • In the 9th C. the Arabs find Ptolemy’s “h Mathematics Syntaxia”, The Mathematical Compilation in Constantanople • Renamed “al Majiasti”, The Greatest Compilation • AKA The Almagest • By the 12th C it is translated into Latin for the King of Sicily

24. Some Words with Arabic Roots

25. Arabic Named Stars

26. Islamic Observing • Observing the sky was permitted as knowing the time was necessary for the five daily prayers • Despite the Koran’s admonition that “No one but God shall know the future”, astrology flourished both privately and at court • Instruments to measure the sky were at first portable but later too big to move around • Bigger images to follow, but you can see some here

27. Two Islamic Observatories • 1120, Cairo • Caliph’s vizier begins construction of large observatory • Murdered the following year • Instruments completed by 1125 • New vizier killed for communicating with Saturn • 1571 Istanbul • Built by Sultan for Astronomer Taqi al-Din • Contemporaneous with Tycho’sHven observatory • Failed to make good predictions about war or health, so it was destroyed in 1580

28. The *Ulugh Beg Sextant • 13th C. Samarkand, Central Asia • A 60° arc of stone with a 40 m radius, aimed at the ecliptic • Observers could measure star positions with a very high precision, aided the compilation of 1,012 stars and the most important catalog of the Middle Ages *provincial governor

29. Still a problem…

30. Europeans • The Crusades • A way to occupy idle knights and heal the Great Schism • 3 main attempts to wrest Jerusalem from Islam, numerous lesser ones • Monastery schools’ goals: • standardizing and preserving Christian dogma • scriptoria • inspired in part by the Irish

32. Changes in Attitude • Ancient wisdom preserved in monasteries • As the Dark Ages* (500-900 AD) gave rise to the High Middle Ages, academic learning flourished *Petrarch in the 1330s said of those who had come before him"amidst the errors there shone forth men of genius, no less keen were their eyes, although they were surrounded by darkness and dense gloom”

34. Thomas Aquinas By the 12th C much ‘new’ knowledge had found its way to Europe, challenging traditional and religious teaching Aquinas successfully merged Aristotle and Christian doctrine, linking the two until the time of Newton

35. Universities • The schools set up by Charlemagne provided the model for greater academic institutions • Added to the quadrivium: • Geometry • Arithmetic • Music • Astronomy • Was the trivium • Grammar • Rhetoric • Logic • The Seven Liberal Arts • Oxford / Cambridge began as monasteries • Scholasticism: arguing conflict down to agreement

36. Many universities were a product of the guild system (High and Late Middle Ages) • Paris: guild of masters • Bologna: guild of students • Different Views of a Scholar’s Job • Greatest happiness comes from contemplation of knowledge already derived (accept what the teacher says), OR • “By doubting we come to inquiry; by inquiring we perceive the truth” (challenge what the teacher says), OR • “You will find more in forests than in books. Woods and stones will teach you more than any master” (find out for yourself) • This last will grow into what we generally call The Scientific Method

37. Medicine Derived from Galen, Hellenistic Greek Health/illness connected to Astrology

38. Technological Advances • Glass mirrors ~ 1190 • “Dry” compass ~ 1250 • Convex lenses / Spectacles ~ 1280 • Mechanical Clocks • Prague Astronomical Clock • 1410, still works today • Mechanism essential for 19th C. equatorial drives

39. Roger Bacon • 1214-1294 Somerset, England • AKA Doctor Mirabilis (wonderful teacher) • Wrote several important works on astronomy, astrology, alchemy, and the calendar • One of the few who advocated experimentation

40. Sacrobosco • AKA John Halifax? John Holywood? – 1256, Yorkshire, England • Educated at Oxford • Taught mathematics at University of Paris • First European to write about Ptolemy's system (On the Sphereof the Worlds); first edition flawed in that it doesn’t explain the motions in the sky Sphæra Mundi

41. Sphæra Mundi • One of the first astronomy books printed; the principal elementary textbook on astronomy for 400 years • 25 editions of Sphæra Mundi printed between 1472-1500, and 40 more by 1650 • 1508 edition: Prime Mover (as in S-P-A philosophy)

42. Alphonsine Tables • Commissioned by King Alphonso X of Toledo in 1252 • Used observations by Islamic astronomers as well as new work by local scholars • Georg Peurbach relied on these tables for his new Theory of the Planets, printed in 1474

43. Georg Peurbach • 1423-1461 Austria • *Began the task of translating the Almagest directly from Greek into Latin • Known as the Epitome of Ptolemy • systematized and clarified Ptolemy's Almagest • used by Christopher Columbus and Nicholas Copernicus • didn't improve the predictive power of Ptolemy's system • didn't resolve problems with calendar • prompted Copernicus to conclude that something was fundamentally wrong with Ptolemy's system *Finished by his student, Johannes Müller

44. Others • Johannes Gutenberg (c.1397-1468) introduced movable type around 1450 • Also prompted the development of optical industry • Because paper was in short supply so they printed small • Poeticonastronomicon(1488) popular, not scholarly text • Pryncycples of Astronomye. Andrew Boord, 1542 • A doctor • Book for doctors on when to apply certain medicines and medications

45. The Medieval Universe Divine Comedy1306-1321 The Nuremberg Chronicle 1493

46. Instruments • Sextant • Astrolabe • Quadrant • Cross staff • Compendium • All pre-telescope era!

47. Sextant

48. Astrolabe

49. Quadrant

50. Cross staff