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  • Hi I'm John Green and this is Crash Course European History.

  • Okay so look: It has been bleak so far.

  • We've had the Black Death, the 116 Years' War, a series of religious wars that culminated

  • with a 30 Years War that killed 20% of Central Europe.

  • We've had the little ice age and witch murdering mania and the Atlantic slave trade but now,

  • now we get to turn our attention to the scientific revolution, which profoundly reshaped our

  • understanding of the universe and ourselves.

  • At last, we are going to make real, undeniable progress.

  • What's that?

  • Oh, Stan tells me that many of these scientists were persecuted for sciencing.

  • Great.

  • But that doesn't stop humans from developing the central insight that reshapes human history.

  • It's about to get really heliocentric around here...

  • [Intro] Before we get into the scientific revolution,

  • I just want to make one broad comment that might be obvious if you've watched previous

  • videos in this series: For most of human history, people did not expect to live healthier or

  • more prosperous lives than previous generations.

  • Sometimes life got better, and sometimes it got worse.

  • It's true that human populations were increasing and that life expectancy was increasing gradually,

  • but the idea that it is normal for human life to get better over time is very new.

  • Today, most European countries have high life expectancy, low maternal mortality, and low

  • rates of absolute poverty.

  • But there have been about 10,000 generations of humans, and we are perhaps the 10th generation

  • who could reliably expect disease burden and child mortality and poverty to steadily decrease

  • in our lifetimes.

  • Well, I'm part of the 10th.

  • You're probably part of the 11th.

  • But regardless, we owe much of this change to the Scientific Revolution.

  • So, like the Reformation, the Scientific Revolution was another break with religious teachings.

  • The Catholic Church taught that the earth was the center of the universe and had been

  • so since the Creation.

  • The sun, moon, and planets traveled around the earth in perfectly circular orbits like

  • the rings of an onion.

  • And beyond the onion was the realm of the divine, whose light pierced through in the

  • form of stars.

  • All this perfect motion was the work of God Himself.

  • And any other understanding of the universe was thus a challenge to God's eternal perfection

  • as described in the scriptures.

  • But, like good Renaissance people, the new astronomers, mathematicians, and their colleagues

  • in other fields declared that old theories needed to be reexamined.

  • The first problem was that the perfect orbits of the planets, and moon, and sun did not

  • fit with observation, causing astronomers to resort to ancient Ptolemaic explanations

  • (basically that planets followed their own circular paths, which also revolved around

  • the Earth).

  • Just before his death in 1543, Polish-born Nicholas Copernicus, a well-connected doctor

  • of canon law and researcher in mathematics, and astronomy, and classical literature, published

  • On the Revolution of the Celestial Spheres.

  • He noted problems with classical astronomical theory and determined that the universe was

  • heliocentric”—that is, the sun, rather than the earth, was at the center.

  • The Catholic Church's reaction to this was negative: the Italian monk Giordano Bruno,

  • for instance, was burned at the stake in 1600 for teaching Copernicus's heliocentric findings.

  • But even earlier than that, in 1572, Danish astronomer Tycho Brahe spotted a new star

  • and in 1577 a new comet, further confirmation that the universe was not immutably and perfectly

  • created.

  • Then, Johannes Kepler's laws of planetary motion announced early in the seventeenth

  • century that the orbits of the planets were ellipticalnot perfectly circular.

  • The solar system was a solar system, and it wasn't an onion.

  • Something other than divine will was keeping the planets apart and in motion.

  • Let's go to the Thought Bubble.

  • By this time, the observations of Galileo Galilei were bringing matters to a head.

  • Galileo was obsessed with science, especially its mathematical features and the

  • calculations at the base of Copernicus's heliocentric theory.

  • Galileo's father had wanted him to become a doctor but mathematics drew him in.

  • It's the oldest story in the world.

  • He invented many tools like an early thermometer and his own telescope, which he used to dramatically

  • improve human understanding of the universe -he was the first person to observe the moons

  • of Jupiter, and the first to understand that the Milky Way was a collection of stars.

  • The telescope also showed irregular spots on the sun, a further sign of heavenly imperfections

  • that went against the beliefs espoused by the Catholic Church.

  • Despite Galileo's prestige as a mathematician, his work on the nature of the universe went

  • too far for the Church.

  • In 1615, Galileo went to Rome to teach the clergy about the heliocentric universe and

  • convince them of its accuracy.

  • In 1616, it was condemned as heretical and Galileo promised not to teach that the earth

  • moved.

  • But, in 1632, he published Dialogue Concerning the Two Chief World Systems in which he described

  • the Ptolemaic system on which the Church based its earth-centered astronomical teachings

  • and the Copernican system.

  • In 1636, the Roman Inquisition found him guilty of heresy and forced him to recant in order

  • to avoid execution.

  • And so Galileo recanted.

  • In 1992, after a 13 year investigation, the Catholic Church finally publicly acknowledged

  • that the judgment against him had been wrong."

  • Thanks Thought Bubble.

  • Centuries later, Albert Einstein would write, “All knowledge of reality starts from experience

  • and ends in it.

  • Because Galileo saw this, and particularly because he drummed it into the scientific

  • world, he is the father of modern physics--indeed, of modern science altogether.”

  • We talk about this at length of course in our history of science series, but for our

  • purposes here it's important to understand that Galileo and other scientists used experimentation

  • and mathematical calculation to confirm or refute hypotheses--and that scientific method

  • was genuinely revolutionary.

  • The scientific approach also spread to other fields of inquiry.

  • Ancient medical theories began to unravel, as English medical doctor William Harvey pronounced

  • the heart to be a pump based on dissections he'd performed.

  • He called the heart “a piece of Machinerythat worked according to natural laws.

  • But it's important to note that even as mechanical theories took hold, prominentnew

  • scientists continued to believed in unseen forces at work in the universe.

  • For example, astrology, positing that the planets and stars influenced people and events,

  • sought to map those influences.

  • Some scientists found it credible --and they pursued all kinds of mystical,

  • and occult, and alchemical investigations.

  • Any revolution needs good propagandists, and people were advertising that thenew

  • scientific values and practices were amazing while also pointing out that the ancient and

  • traditional ones were full of errors.

  • English politician Francis Bacon was foremost among these science propagandists, chiding

  • everyone who was using the old paradigms and models of the universecalling them worthless

  • ancients.

  • Bacon, like others at the time, created his own careful observations, and experiments,

  • and sought to use reason.

  • There was, he said, a scientific method to be followed.

  • One needn't rely on past accounts that were copies of copies of copies--one should ask

  • their own questions, and do their own experiments to find the answer to those questions, experiments

  • that other people could then replicate to confirm--or refute--the findings.

  • And this became the basis for the new scientific method as Bacon laid it out in The Advancement

  • of Learning.

  • His process of reaching the truth and drawing conclusions from specific, reliable facts

  • or evidence is called inductive reasoning.

  • And a collection of reliable, verified evidence was essential, according to Bacon, notold

  • wives' fablesor, as another new scientist put it, notmaunderings of a babbling hag”—words

  • that were part of the discourse of witches who were being tried and murdered at the time.

  • And then there was French philosopher René Descartes who moved speculation about the

  • new science to a still different methodological register by looking at the mind.

  • Descartes noted that reasonthinkingwas made for verification, so thinking on one's

  • own was crucial.

  • Because, otherwise there were so many facts that one could essentially become skeptical

  • about whether truth actually existed.

  • Like imagine a world where there are facts, but there are alsoalternatefacts,

  • and you have to choose between your set of facts before you reach a conclusion.

  • That would be unlivable!

  • So Descartes set out to prove the one thing he felt he could be sure of.

  • His own existence.

  • And in doing so, he prioritized his own power of thinking: “I think therefore I am.”

  • But he also prioritized doubt, which is central to the scientific method--Descartes also wrote,

  • We cannot doubt of our existence while we doubt.”

  • In short, our ability to conceive of doubt about whether we exist, is proof that we exist.

  • By privileging the role that thought, and with it questioning, play in discovering truth,

  • Descartes had developed deductive reasoning: that is, faith in the rational power of the

  • mind to generate specific truths from its own theories or power of thinking.

  • (By the way in addition to a Crash Course in the history of science, we also have a

  • crash course in philosophy, where you can learn more about Descartes.)

  • Okay, let's turn our attention to Isaac Newton, who synthesized new methodology and

  • his own findings in his universal laws of motion.

  • Newton was a scientist with a reputation for following every lead, Newton practiced alchemythat

  • is the quest for secret formulae and practices, especially an entity called the philosopher's

  • stone that could turn lead or other base metals into gold.

  • Which by the way would be an inflationary disaster, but fortunately it's impossible.

  • But I think that's important to note because it reminds us that not every lead being followed

  • by scientists--then or now--results in big discoveries, but part of the glory of science

  • is learning what doesn't work.

  • Also, it reminds us that in the 17th century, many of the smartest people in the world believed

  • in alchemy, a nice opportunity to reflect on what false promises contemporary humans

  • might believe.

  • At any rate, while studying alchemy, he also pulled together the findings of his predecessors

  • into mathematical laws for the functioning of the universe.

  • He quantified the major constructs of mass, inertia, force, velocity and acceleration

  • and produced the law of gravitation.

  • And he encapsulated all his findings in his Principia Mathematica in 1687.

  • For Newton, the universe was indeed a fantastic, regular, and all encompassing machine, yet

  • it was a machine still tinged with the mysteries that he continued to decipher, and to be fair

  • that we are still deciphering today.

  • By the early decades of the seventeenth century, contact with the wider world led to other

  • kinds of scientific investigations.

  • Adventurers brought back to Europe new species of plants, and textiles, minerals, animal

  • life that sparked wonder and scientific probing.

  • One of the first to venture out was Portuguese doctor Garcia da Orta.

  • He traveled first to Goa, India, studying plants like aloe, cannabis, coconut, and ginger.

  • In 1563, he published Conversations on the Simples, Drugs and Medicinal Substances of

  • India, which advanced the use of plants as medicine.

  • Local people were key to major plant discoveries: Dr. da Orta, for instance, learned from healers

  • in South Asia, while in the 1620s local people in Lima cured a Jesuit priest with malaria

  • by giving him the medicine they used--quina-quina.

  • Eventually this healing bark was turned into quinine, a malaria medication that allowed

  • Europeans to expand their empires more deeply into Africa and South America.

  • In the cases of both Doctor da Orta and the Jesuits in Peru, European advances, like others

  • that would follow, depended on gathering up scientific and medical knowledge from other

  • people.

  • Within Europe, scientific networks developed around heliocentrism and also around other

  • new ideas just as they had in the Renaissance.

  • Like Erasmus and his correspondents, Galileo and scientists across Europe wrote one another

  • and published books about their findings.

  • The Royal Society of London had itsrepublic of letters.”

  • And communication like that became pivotal both to verification and to convince as much

  • of the public as possible that these new scientific discoveries were valid.

  • Amid warfare, the little ice age, and famine, these scientists were corresponding about

  • comets, windmills, pumps, and blood vessels.

  • Theories about vision and atomism passed around in letters, reached as far as the Ottoman

  • Empire and Japan.

  • Governments also got in on the Scientific Revolution, giving scientists like Galileo

  • stipends to support their work, and labeling themCourt Mathematicians,” which added

  • prestige both to the scientist and the royal court itself.

  • Louis XIV of France started one of the most prestigious scientific academiesthe royal

  • Academy of Sciencesin 1666.

  • And Theaters of anatomy, where dissections and other physiological demonstrations occurred,

  • also received official sponsorship.

  • Oh, did the globe open at last?

  • Is Yorick in there?

  • Alas, poor Yorick...I didn't know eyebrows were a skeletal feature.

  • For the first, like, 98 percent of history, we knew so little about how all of this works.

  • Look, I'm never going to be a ventriloquist, OK?

  • Stan, this isn't a real skull, is it?

  • Ugh!

  • We will examine the mounting power of the state next week beyond its sponsorship of

  • science.

  • For the moment, let's reflect on the ways in which so-called new scientists during the

  • sixteenth and seventeenth centuries bravely took religious scriptures out of the workings

  • of astronomy and the heavens.

  • Instead of a divine hand at work, by the time of Newton, universal laws for the operation

  • of the solar system and physical bodies had been established.

  • Although most people believed in God, many of them earnestly so, they also followed a

  • developing scientific method and additionally established faith in their own rational powers.

  • This way of looking at the world would prove so important that less than 350 years after

  • Galileo became the first person to observe the moon's cratered surface, human beings

  • would step foot on that surface.

  • Thanks for watching.

  • I'll see you next time.

Hi I'm John Green and this is Crash Course European History.

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科学革命。クラッシュ・コース ヨーロッパの歴史 #12 (Scientific Revolution: Crash Course European History #12)

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    林宜悉 に公開 2021 年 01 月 14 日
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