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Hi I'm John Green and this is Crash Course European History.
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Okay so look: It has been bleak so far.
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We've had the Black Death, the 116 Years' War, a series of religious wars that culminated
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with a 30 Years War that killed 20% of Central Europe.
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We've had the little ice age and witch murdering mania and the Atlantic slave trade but now,
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now we get to turn our attention to the scientific revolution, which profoundly reshaped our
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understanding of the universe and ourselves.
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At last, we are going to make real, undeniable progress.
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What's that?
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Oh, Stan tells me that many of these scientists were persecuted for sciencing.
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Great.
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But that doesn't stop humans from developing the central insight that reshapes human history.
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It's about to get really heliocentric around here...
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[Intro] Before we get into the scientific revolution,
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I just want to make one broad comment that might be obvious if you've watched previous
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videos in this series: For most of human history, people did not expect to live healthier or
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more prosperous lives than previous generations.
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Sometimes life got better, and sometimes it got worse.
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It's true that human populations were increasing and that life expectancy was increasing gradually,
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but the idea that it is normal for human life to get better over time is very new.
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Today, most European countries have high life expectancy, low maternal mortality, and low
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rates of absolute poverty.
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But there have been about 10,000 generations of humans, and we are perhaps the 10th generation
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who could reliably expect disease burden and child mortality and poverty to steadily decrease
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in our lifetimes.
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Well, I'm part of the 10th.
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You're probably part of the 11th.
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But regardless, we owe much of this change to the Scientific Revolution.
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So, like the Reformation, the Scientific Revolution was another break with religious teachings.
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The Catholic Church taught that the earth was the center of the universe and had been
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so since the Creation.
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The sun, moon, and planets traveled around the earth in perfectly circular orbits like
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the rings of an onion.
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And beyond the onion was the realm of the divine, whose light pierced through in the
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form of stars.
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All this perfect motion was the work of God Himself.
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And any other understanding of the universe was thus a challenge to God's eternal perfection
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as described in the scriptures.
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But, like good Renaissance people, the new astronomers, mathematicians, and their colleagues
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in other fields declared that old theories needed to be reexamined.
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The first problem was that the perfect orbits of the planets, and moon, and sun did not
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fit with observation, causing astronomers to resort to ancient Ptolemaic explanations
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(basically that planets followed their own circular paths, which also revolved around
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the Earth).
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Just before his death in 1543, Polish-born Nicholas Copernicus, a well-connected doctor
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of canon law and researcher in mathematics, and astronomy, and classical literature, published
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On the Revolution of the Celestial Spheres.
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He noted problems with classical astronomical theory and determined that the universe was
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“heliocentric”—that is, the sun, rather than the earth, was at the center.
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The Catholic Church's reaction to this was negative: the Italian monk Giordano Bruno,
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for instance, was burned at the stake in 1600 for teaching Copernicus's heliocentric findings.
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But even earlier than that, in 1572, Danish astronomer Tycho Brahe spotted a new star
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and in 1577 a new comet, further confirmation that the universe was not immutably and perfectly
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created.
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Then, Johannes Kepler's laws of planetary motion announced early in the seventeenth
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century that the orbits of the planets were elliptical—not perfectly circular.
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The solar system was a solar system, and it wasn't an onion.
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Something other than divine will was keeping the planets apart and in motion.
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Let's go to the Thought Bubble.
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By this time, the observations of Galileo Galilei were bringing matters to a head.
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Galileo was obsessed with science, especially its mathematical features and the
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calculations at the base of Copernicus's heliocentric theory.
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Galileo's father had wanted him to become a doctor but mathematics drew him in.
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It's the oldest story in the world.
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He invented many tools like an early thermometer and his own telescope, which he used to dramatically
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improve human understanding of the universe -he was the first person to observe the moons
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of Jupiter, and the first to understand that the Milky Way was a collection of stars.
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The telescope also showed irregular spots on the sun, a further sign of heavenly imperfections
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that went against the beliefs espoused by the Catholic Church.
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Despite Galileo's prestige as a mathematician, his work on the nature of the universe went
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too far for the Church.
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In 1615, Galileo went to Rome to teach the clergy about the heliocentric universe and
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convince them of its accuracy.
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In 1616, it was condemned as heretical and Galileo promised not to teach that the earth
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moved.
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But, in 1632, he published Dialogue Concerning the Two Chief World Systems in which he described
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the Ptolemaic system on which the Church based its earth-centered astronomical teachings
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and the Copernican system.
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In 1636, the Roman Inquisition found him guilty of heresy and forced him to recant in order
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to avoid execution.
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And so Galileo recanted.
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In 1992, after a 13 year investigation, the Catholic Church finally publicly acknowledged
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that the judgment against him had been wrong."
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Thanks Thought Bubble.
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Centuries later, Albert Einstein would write, “All knowledge of reality starts from experience
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and ends in it.
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… Because Galileo saw this, and particularly because he drummed it into the scientific
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world, he is the father of modern physics--indeed, of modern science altogether.”
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We talk about this at length of course in our history of science series, but for our
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purposes here it's important to understand that Galileo and other scientists used experimentation
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and mathematical calculation to confirm or refute hypotheses--and that scientific method
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was genuinely revolutionary.
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The scientific approach also spread to other fields of inquiry.
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Ancient medical theories began to unravel, as English medical doctor William Harvey pronounced
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the heart to be a pump based on dissections he'd performed.
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He called the heart “a piece of Machinery” that worked according to natural laws.
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But it's important to note that even as mechanical theories took hold, prominent “new”
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scientists continued to believed in unseen forces at work in the universe.
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For example, astrology, positing that the planets and stars influenced people and events,
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sought to map those influences.
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Some scientists found it credible --and they pursued all kinds of mystical,
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and occult, and alchemical investigations.
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Any revolution needs good propagandists, and people were advertising that the “new”
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scientific values and practices were amazing while also pointing out that the ancient and
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traditional ones were full of errors.
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English politician Francis Bacon was foremost among these science propagandists, chiding
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everyone who was using the old paradigms and models of the universe—calling them worthless
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ancients.
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Bacon, like others at the time, created his own careful observations, and experiments,
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and sought to use reason.
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There was, he said, a scientific method to be followed.
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One needn't rely on past accounts that were copies of copies of copies--one should ask
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their own questions, and do their own experiments to find the answer to those questions, experiments
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that other people could then replicate to confirm--or refute--the findings.
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And this became the basis for the new scientific method as Bacon laid it out in The Advancement
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of Learning.
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His process of reaching the truth and drawing conclusions from specific, reliable facts
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or evidence is called inductive reasoning.
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And a collection of reliable, verified evidence was essential, according to Bacon, not “old
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wives' fables” or, as another new scientist put it, not “maunderings of a babbling hag”—words
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that were part of the discourse of witches who were being tried and murdered at the time.
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And then there was French philosopher René Descartes who moved speculation about the
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new science to a still different methodological register by looking at the mind.
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Descartes noted that reason—thinking—was made for verification, so thinking on one's
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own was crucial.
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Because, otherwise there were so many facts that one could essentially become skeptical
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about whether truth actually existed.
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Like imagine a world where there are facts, but there are also “alternate” facts,
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and you have to choose between your set of facts before you reach a conclusion.
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That would be unlivable!
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So Descartes set out to prove the one thing he felt he could be sure of.
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His own existence.
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And in doing so, he prioritized his own power of thinking: “I think therefore I am.”
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But he also prioritized doubt, which is central to the scientific method--Descartes also wrote,
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“We cannot doubt of our existence while we doubt.”
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In short, our ability to conceive of doubt about whether we exist, is proof that we exist.
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By privileging the role that thought, and with it questioning, play in discovering truth,
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Descartes had developed deductive reasoning: that is, faith in the rational power of the
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mind to generate specific truths from its own theories or power of thinking.
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(By the way in addition to a Crash Course in the history of science, we also have a
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crash course in philosophy, where you can learn more about Descartes.)
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Okay, let's turn our attention to Isaac Newton, who synthesized new methodology and
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his own findings in his universal laws of motion.
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Newton was a scientist with a reputation for following every lead, Newton practiced alchemy—that
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is the quest for secret formulae and practices, especially an entity called the philosopher's
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stone that could turn lead or other base metals into gold.
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Which by the way would be an inflationary disaster, but fortunately it's impossible.
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But I think that's important to note because it reminds us that not every lead being followed
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by scientists--then or now--results in big discoveries, but part of the glory of science
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is learning what doesn't work.
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Also, it reminds us that in the 17th century, many of the smartest people in the world believed
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in alchemy, a nice opportunity to reflect on what false promises contemporary humans
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might believe.
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At any rate, while studying alchemy, he also pulled together the findings of his predecessors
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into mathematical laws for the functioning of the universe.
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He quantified the major constructs of mass, inertia, force, velocity and acceleration
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and produced the law of gravitation.
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And he encapsulated all his findings in his Principia Mathematica in 1687.
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For Newton, the universe was indeed a fantastic, regular, and all encompassing machine, yet
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it was a machine still tinged with the mysteries that he continued to decipher, and to be fair
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that we are still deciphering today.
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By the early decades of the seventeenth century, contact with the wider world led to other
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kinds of scientific investigations.
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Adventurers brought back to Europe new species of plants, and textiles, minerals, animal
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life that sparked wonder and scientific probing.
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One of the first to venture out was Portuguese doctor Garcia da Orta.
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He traveled first to Goa, India, studying plants like aloe, cannabis, coconut, and ginger.
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In 1563, he published Conversations on the Simples, Drugs and Medicinal Substances of
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India, which advanced the use of plants as medicine.
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Local people were key to major plant discoveries: Dr. da Orta, for instance, learned from healers
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in South Asia, while in the 1620s local people in Lima cured a Jesuit priest with malaria
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by giving him the medicine they used--quina-quina.
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Eventually this healing bark was turned into quinine, a malaria medication that allowed
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Europeans to expand their empires more deeply into Africa and South America.
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In the cases of both Doctor da Orta and the Jesuits in Peru, European advances, like others
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that would follow, depended on gathering up scientific and medical knowledge from other
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people.
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Within Europe, scientific networks developed around heliocentrism and also around other
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new ideas just as they had in the Renaissance.
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Like Erasmus and his correspondents, Galileo and scientists across Europe wrote one another
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and published books about their findings.
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The Royal Society of London had its “republic of letters.”
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And communication like that became pivotal both to verification and to convince as much
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of the public as possible that these new scientific discoveries were valid.
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Amid warfare, the little ice age, and famine, these scientists were corresponding about
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comets, windmills, pumps, and blood vessels.
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Theories about vision and atomism passed around in letters, reached as far as the Ottoman
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Empire and Japan.
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Governments also got in on the Scientific Revolution, giving scientists like Galileo
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stipends to support their work, and labeling them “Court Mathematicians,” which added
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prestige both to the scientist and the royal court itself.
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Louis XIV of France started one of the most prestigious scientific academies—the royal
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Academy of Sciences—in 1666.
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And Theaters of anatomy, where dissections and other physiological demonstrations occurred,
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also received official sponsorship.
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Oh, did the globe open at last?
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Is Yorick in there?
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Alas, poor Yorick...I didn't know eyebrows were a skeletal feature.
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For the first, like, 98 percent of history, we knew so little about how all of this works.
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Look, I'm never going to be a ventriloquist, OK?
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Stan, this isn't a real skull, is it?
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Ugh!
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We will examine the mounting power of the state next week beyond its sponsorship of
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science.
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For the moment, let's reflect on the ways in which so-called new scientists during the
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sixteenth and seventeenth centuries bravely took religious scriptures out of the workings
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of astronomy and the heavens.
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Instead of a divine hand at work, by the time of Newton, universal laws for the operation
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of the solar system and physical bodies had been established.
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Although most people believed in God, many of them earnestly so, they also followed a
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developing scientific method and additionally established faith in their own rational powers.
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This way of looking at the world would prove so important that less than 350 years after
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Galileo became the first person to observe the moon's cratered surface, human beings
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would step foot on that surface.
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Thanks for watching.
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I'll see you next time.