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Background of the Scientific Revolution. Three Traditions provide the context for scientific revolution:. Practical inventions Magic and astrology University education These begin to come together in the 1400s. Practical Inventors.
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Three Traditions provide the context for scientific revolution: • Practical inventions • Magic and astrology • University education These begin to come together in the 1400s
Practical Inventors • Architects of fortifications, mills, windmills, municipal buildings. • Craftsmen who made swords, and craftsmen who designed artillery. • Clockmakers. • Shipwrights as well as artisans who made instruments for ships. • Printers who tinkered with presses • Lens grinders who made eye glasses All these men (and occasionally women) measured, calculated, observed, experimented to make it easier to do some aspect of daily work.
Miniature of Richard of Wallingford, 14th century Abbot of St. Albans, mathematician and inventor of a mechanical astronomical clock, is shown in this miniature seated at his desk measuring with a pair of compasses.
A Printing Press, was a machine that took a good deal of practical ingenuity From University of Texas Gutenberg exhibition • http://www.hrc.utexas.edu/exhibitions/permanent/gutenberg/html/4.html
This Vermeer sketch belies the complicated mechanism inside a nine ton windmill. • Vermeer sketch of a windmill.
Town Hall clock in Esslingen, Germany • This Astronomical clock completed about 1592. It has movable figures (eagle, the goddesses of Justice and Temperance and figures of the planets)
Leonardo da Vinci • Machine for Storming Walls --1480 drawing
Vasa. a warship that was built for Gustavus Adolphus of Sweden from 1626 to 1628. Unfortunately, It sank on its maiden voyage.
Quadrant This instrument, shaped like a quarter of a circle, measured the angle from the vertical - not horizontal - and the line of sight to the body. It was suspended from a ring and had a weighted line hanging down, which crossed one of the angle numbers marked on the ring. Columbus used one, but after trying it, it's hard to imagine how it was held stable! The astrolabe is an instrument that provides a picture of how the sky looks at the observer's latitude and time. It has moveable parts that allow it to be set for specific dates and times, and interchangeable templates that allow latitude to be set.
The illustration is from Liber Chronicarum1493 in which the same wood cut illustrations were used multiple times to depict various different people. The 14th century eyeglasses above are a reproduction.
Magic, Astrology, Alchemy • Every medieval prince or king had a “Magus”, who helped him make decisions by consulting the stars. • Their forecasts needed to be carefully worded, or they needed a good deal of luck.
The magus sometimes advised on herbal remedies based on astrology. • The English astrologer, Richard Ball wrote: “...it is also necessary, that the Planet governing the Herb you gather, be ruler of the Day (as well as Hour) as for Example: Suppose you gather Herbs governed by Moon, Monday being assigned to her government, that Day is most proper to gather her herbs in, having regard to the Hour she rules the same Day which is every Monday at Sun Rise: the like you may observe of all the Herbs, governed by the Planets...so that an ingenious Man cannot be to seek in gathering, compounding or applying his medicines according to the Nature of the Distemper and Parts afflicted.” • Astro-Physical Compendium 1697
This sixteenth century immigrant to Europe from Africa is thought by some to have been a magus. • Portrait of an African Man by Jan Mostaert (ca. 1520-1530) • Source: Rijksmuseum Amsterdam, Netherlands
The Contribution of Astrology and Alchemy. • Though both their areas of knowledge are discredited today, they are nonetheless important. Practitioners had a sense that there was a vast system that bound all nature together. They experimented and observed. Kepler, for example, was an astrologist, and Isaac Newton was an alchemist. • The idea that there were secrets to be learned by combining substances or that observing the stars would yield valuable information was a critical precondition for the scientific revolution.
Alchemists were popular subjects for painters Jan van der Straet The Alchemist's Workshop (1570)
Pieter Brueghel the Elder- painted this slightly more critical scene in1525
Medieval and Renaissance Universities were communities of scholars
Universities began to develop in western Europe in the 13th century, most notably at Paris, France, and Bologna, Italy. • Instruction in medieval universities often took the form of lectures, with teachers, who were called masters, reading aloud from a text while students followed along.
This map is not easy to read, but just a glance shows you that by the 16th century there were a substantial number of Universities. • From the Historical Atlas by William R. Shepherd, 1923
Sometimes, rarely, women were allowed to sit in on lectures.
The “Liberal Arts” were not very liberal • During the early Renaissance students copied or read the astronomy of Ptolemy, physics from Aristotle, anatomy from Galen---all about 1000 years old. • These texts were thought to hold the truth. The study of physics meant elaborating on Aristotle, and without printing that was pretty tedious. • Despite their limitations, these universities were centers of knowledge and scholarship—and argument and logic.
Until the 1400s these Three Traditions operated independently. • The artisan worked on improving something needed for daily work…. • The magus worked for a prince or other important helping him to make decisions with the help of the stars, but his observations or calculations were not applied more widely… • Many universities kept teaching what they had always taught, sometimes adding more mathematics….. • In the 16th and 17th centuries they begin to come together
Paracelsus • An early 16th century figure who brought at least two of these traditions into some sort of synthesis. He had a university degree in medicine, but was also steeped in alchemy and magic . • As a result he developed metal cures ---including using mercury for syphilis, which turned out to be effective in small doses. • He famously burned the works of Galen in a public square in Basil. ‘Give heed to those who find something new!” he said.
But others would come along – especially in the 17th century—who would do more combining…. • Copernicus • Kepler • Galileo • William Harvey • And the idol of the l8th century, • Isaac Newton • And many others who would change the way in which Europe understood the world.
New Ideas in Astronomy If you’d been a university student in 1450 you would have been taught Ptolemy’s model of the universe. Ptolemy wrote in the first centery AD, so these ideas were over 1000 years old, though they were much newer to Europe.
The assumption was that the planets and the sun must move in perfect circles. The only way to make the observations work with that assumption was to assume that there were also epicycles.
Copernicus • After many years of study concluded that observations and math worked much better if one began with the assumption that the earth moved around the sun. This challenged ideas that had become part of the cosmos that Catholic theologians believed in.
This new Heliocentric model:partly explained the retrograde motion of the planets The Heliocentric model:–partly explained the retrograde motion of the planets–could not predict their exact locations, but ephemerides based on Copernicus (Prutenic Tables) were much more accurate then those based on Ptolemaic system (Alfonsine Tables).
Johannes Kepler • Came to work in the observatory of a Danish astonomer, Tycho Brahe
Elliptical Orbits! • Kepler figured out the next step: the circles were what was causing the problem. The Ellipse worked!
Galileo • Made observations with a telescope, which he constructed using new magnifying lenses. He got into trouble when he was accused of promulgating the Copernican theory as fact. • The Trial of Galileo
Galileo showed that the moon was anything but a perfect sphere. He also saw Jupiter had moons.
But it was in the Dialogue of Two World Systems that Galileo got into trouble
