Presentation on theme: "The Scientific Revolution"— Presentation transcript:
1The Scientific Revolution The Scientific Revolution marked the beginning of a dramatic shift in how people viewed the world. The medieval and early modern European outlook had been dominated by religion. As a result of this revolution, many came to see the world predominantly in secular and scientific ways. In the short term, the Scientific Revolution set the stage for the Enlightenment; its long-term repercussions can still be felt today.
2What Was the Scientific Revolution? A revolution in human understanding and knowledge about the physical universe17th centuryBegan with Kepler, GalileoEnded with NewtonThe Scientific Revolution is generally viewed as a 17th-century phenomenon. Most historians consider it to have started with the astronomical discoveries of individuals like Kepler and Galileo and ended with the publication of Newton’s major works. We will describe these “bookends” of the Scientific Revolution in greater detail later in this discussion.
3The BIG PICTURE:The scientific revolution is historically important for three reasons:it laid the basis for our modern view of the world as a rational, ordered placeit shifted the nature of discourse in "natural philosophy" from reason (deductive) to empirical (inductive) methodFinally, it affected the thinking of a wide range of people from poets and philosophers to practical men of politics and economics
4“Science” Before the Scientific Revolution Based almost entirely on reasoningExperimental method or observation wasn’t used at allScience in medieval timesAlchemyAstrologytraditionMore than anything else, science is a habit of mind. It involves using reason, observation, testing, and systematic thought to uncover truths about the world and about people, animals, and things in the world. “Science” as we know it today didn’t really exist before the Scientific Revolution. Instead, scientists in ancient and medieval times were really philosophers who drew conclusions based on deductive reasoning; they rarely conducted practical experiments.Much of what was considered “science” in medieval times had very little basis in fact and drew more from superstition and religious belief. Similar in many ways to chemistry, alchemy aimed to develop potions that would do things such as change iron into gold, cure all disease, or bestow immortality. Astrology was based on the concept that the positions and conditions of celestial bodies could influence human existence, both positively and negatively. Practitioners of astrology would often claim that human suffering (including sickness) could be explained by the position of the stars.A medieval alchemist
5Factors Leading to the Scientific Revolution Rise of universitiesContact with non-Western societiesThe RenaissanceExplorationA number of factors helped lay the groundwork for the Scientific Revolution:The first universities appeared during the Middle Ages. Although universities initially focused primarily on topics like law and philosophy, they gradually expanded their offerings and came to establish professorships in areas such as mathematics, astronomy, medicine, and other science-related disciplines. Universities brought together leading scientific minds, encouraged intellectual debate, and sparked interest in research and discovery.Muslim scholars of the Middle Ages made several important mathematical and scientific discoveries. During the 12th and 13th centuries, both the Crusades and the expansion of trade networks brought Europeans into greater contact with Muslim societies. Both cultural and intellectual exchanges occurred; this infusion of new ideas helped improve Europeans’ understanding of mathematical principles in particular and of science in general.As the Renaissance dawned and inspired advances in art and literature, educated Europeans began to look beyond the church and the Bible for knowledge and truth. In addition to serving as patrons of the arts, wealthy families such as the Medicis in Italy also supported scientific research.The Age of Exploration also provided impetus for the Scientific Revolution. The challenges of navigating across the Atlantic Ocean and around Africa motivated advances in mathematics, astronomy, and cartography (mapping). European monarchs interested in expanding their overseas empires (including King John of Portugal, King Ferdinand and Queen Isabella of Spain, and Queen Elizabeth I and King Charles II of England) provided funding and/or support for scientific research.
6Rationalism Reason, not tradition, is the source of all knowledge René Descartes (1596–1650)French philosopher and mathematicianCogito ergo sum (“I think, therefore, I am”)Deductive reasoningThe philosophy of rationalism holds that all knowledge comes from reason. René Descartes was one of the most important philosophers and mathematicians of his time; many regard him as the father of modern rationalism. In Discourse on Method and The Meditations, he reasoned that all of his prior knowledge was subject to doubt because it was based on traditional beliefs rather than on reason. He pondered what he could honestly say he knew to be true, going so far as to doubt whether he was awake or dreaming—or if he even existed. He then began to reconstruct his world view: he knew that his thoughts existed, which then suggested the existence of a thinking being—himself. Descartes then came to his famous conclusion, “Cogito ergo sum,” which means “I think, therefore, I am.”Descartes’ conclusions were based on deductive reasoning, which involves using a general principle to draw conclusions about a specific instance. For example, once he had come up with Cogito ergo sum, he used it to draw a further conclusion: because the mind “cannot be doubted but the body and material world can, the two must be radically different.” In other words, Descartes drew a clear distinction between mind and matter—an idea that helped break down superstitions that had influenced science in the medieval era.René Descartes
7EmpiricismThe belief that experience is the only true source of knowledgeRoger BaconShift toward empiricism a hallmark of the Scientific RevolutionHelped lead to the development of the scientific methodThe philosophy of empiricism holds that the only real way to acquire knowledge is through experience—that is to say, through observation. Empiricism stands in opposition to rationalism, which holds that knowledge could be acquired through the exercise of one’s reason alone. Some of the first writings on empiricism came in the 13th century from Roger Bacon, an English scholar. In his work Opus Maius, Bacon wrote, “There are two modes of knowledge, through argument and experience. ‘Argument’ brings conclusions and compels us to concede them, but it does not cause certainty nor remove doubt in order that the mind may remain at rest in truth, unless this is provided by experience.”One of the hallmarks of the Scientific Revolution was the new focus on empiricism. Empiricism also helped lead to the development of the scientific method.Roger Bacon
8Francis Bacon and the Scientific Method 1561–1626English philosopher and empiricistInductive reasoningArgued for experimental methodologyEnglish philosopher Sir Francis Bacon laid the theoretical groundwork for what became known as the scientific method. His ideas about science incorporated what is known as inductive reasoning, which involves using concrete facts to extrapolate broader conclusions. (Inductive reasoning is the opposite of deductive reasoning.) Bacon argued that scientists should work from the specific (observable data) to the general (rules and theories based on that data). He believed that all scientific research should rely on careful observation and experimentation rather than simply relying on one’s own thought and reasoning, as earlier scientific thinkers had. The data obtained should then be recorded and analyzed according to logic and reason, then used to produce a testable hypothesis.
9Science as a multiple-step process: The Scientific MethodScience as a multiple-step process:1. Observe an object or phenomenon2. Develop a theory that explains the object or phenomenon3. Test the theory with experiments
10Roots of Scientific Thought: Aristotle 4th century BCE Greek philosopher and scientistWrote several scientific worksHis work laid the foundation for scientific study through the medieval eraGravity/Theory of falling objectsAstronomy: Crystal spheresAristotle was a Greek philosopher and scientist who lived in the 4th century BCE. He is considered one of the most influential philosophers in Western thought. Although much of his work concerned topics like politics and ethics, he also wrote many works concerning biology, zoology, and physics. His works provided the theoretical foundation for science for centuries to come. Although Aristotle came up with many brilliant insights into philosophy and government, in science he relied on reason rather than empirical evidence and did not conduct experiments; consequently, many of his conclusions were incorrect. For example, he hypothesized that gravity occurred because objects were attracted to the Earth’s core, and theorized that heavier objects would fall to earth more quickly than lighter ones. He also came up with a theory of astronomy which hypothesized that a motionless Earth lay at the center of the universe surrounded by concentric crystal spheres. One sphere held the moon, another the sun, others held each of the five known planets at the time, and the last held what the ancient Greeks referred to as the “fixed stars.”
11Roots of Scientific Thought: Ptolemy 2nd century CE Greek astronomer, mathematician, and geographerThe Almagest (Syntaxis)Geocentric (earth-centered) model of the universeMotion of the planetsPtolemy, another ancient Greek, was an influential mathematician, astronomer, and geographer who lived in the 2nd century CE. Around 150, he wrote the Almagest (also known as the Syntaxis), his most important work. In it, he provided a comprehensive overview of mathematical astronomy and formalized the concept of a geocentric (meaning “earth-centered”) model of the universe. He also offered detailed mathematical rules describing the motion of each of the planets.
12Models of the Universe: Geocentric vs. Heliocentric Geocentric: the Earth is at the center of the universe; all heavenly bodies move around the EarthHeliocentric: the Sun is at the center of the universe; all heavenly bodies move around the Sun—including the EarthDerived from the Greek words “geo” (meaning earth) and “centron” (meaning center), the geocentric view were generally the view pushed by Aristotle and Ptolemy (see above). Geocentricism was officially endorsed by the Catholic Church and taught at religious schools and universities.Derived from the Greek works “helios” (meaning sun) and “centron” (meaning center), the heliocentric conception was the most prominent theory pushed during the Scientific Revolution.
13Nicholas Copernicus (1473–1543) Polish astronomer and mathematicianCommentariolus (1514)Concerning the Revolutions of the Celestial Spheres (1543)In 1514, Copernicus wrote Commentariolus, a short, handwritten notebook of observations in which he laid out the foundations of his heliocentric theories. He did not sign his name to Commentariolus and distributed it only to a few friends, fearing that the controversial nature of his thoughts might provoke the anger of the Catholic Church. The following year, however, he began to write Concerning the Revolutions of the Celestial Spheres, in which he expanded on the heliocentric model he had proposed in Commentariolus. He worked on the book for the rest of his life; it was finally published just before his death in Despite the importance of Copernicus’ work, at the time his theories did little more than spark debate among scientific thinkers and had little initial impact outside of academic circles. His ideas would provide the foundation for the revolutionary work of later scientists.
14Tycho Brahe (1546–1601) Danish astronomer Amassed accurate astronomical dataTheorized a system distinct from both the Ptolemaic and Copernican onesArgued that the Moon and Sun revolve around the Earth while other planets revolve around the SunBEST. DEATH. EVER.Tycho Brahe is more often referred to by his first name, not his last. He made a name for himself as an astronomy lecturer at the University of Copenhagen and in the late 1570s came to the attention to one of the great “enlightened monarchs,” Frederick II of Prussia. Frederick offered to provide the funds for Tycho to construct an observatory; built on an island near Copenhagen, Tycho’s Uraniburg observatory became regarded as the finest in Europe. At Uraniburg, Tycho designed and built several new astronomical instruments and used them to create some of the most accurate star charts of the time. He also owned both a paper mill and a printing press and self-published a number of his works, including The Dream, considered one of the first works of science fiction.Tycho is important largely because he gathered a huge amount of astronomical data with unprecedented accuracy. He also came up with a theory of the heavens that offered an alternative to both the Ptolemaic and Copernican models, arguing that the Sun and the Moon revolved around Earth while other planets in the solar system revolved around the Sun. The latter assertion helped answer observation-based criticisms about earlier conceptions of the Universe without requiring a heliocentric model of the universe.
15Johannes Kepler (1571–1630) German astronomer and mathematician Student of TychoDidn’t agree with Tycho’s interpretation of dataDisagreed with Copernicus, claiming that other bodies moved in elliptical motion, as opposed to circular motionsTheorized three laws of planetary motion using Tycho’s dataKepler originally studied theology but ended up as a professor of mathematics. As a student of Tycho, he studied both his teacher’s works as well as the writings of Copernicus. Kepler claimed that while Tycho’s data was correct, his interpretations of the data were incorrect; he further argued that Tycho’s data actually proved Copernicus correct.Kepler also took issue with Copernicus’ claim that astronomical bodies moved in circles, asserting instead that they moved in elliptical patterns—an assertion that later proved correct. Kepler used Tycho’s data and his own observations to develop three laws of planetary motion and proved the core of heliocentric theory.
16Kepler’s Three Laws of Planetary Motion Law of Ellipses: Planets orbit the sun in elliptical patternsLaw of Equal Areas: The speed of planetary motion changes constantly depending on the distance from the SunLaw of Harmonies: Compares the movement of all the planets, claiming a similarity in their motionKepler’s data led him to propose three theories concerning planetary motion:The Law of Ellipses: Asserts that planets orbit the sun elliptically (i.e., in oval patterns). This law explained why theories that claimed that planets orbited the Sun or Earth in circular patterns were inconsistent with observed data.The Law of Equal Areas: Claims that the speed of planetary motion changes constantly depending on the planet’s distance from the Sun. Planets move faster when closer to the Sun, slower when further away.Law of Harmonies: Compares the movement of all the planets using ratios, claiming a similarity in the motions of all the planets in the galaxy.
17Galileo Galilei (1564–1642) Italian mathematician, astronomer “Father of Science”Telescopes and astronomical discoveriesTheory of falling objects; disproved AristotleGalileo is considered the father of modern physics, astronomy, and more generally the “Father of Science.” He created several different telescopes (improving the power of with each successive model) and used them to record extraordinary amounts of data. His interpretations of the data yielded some remarkable discoveries, including:Stars were farther away than planetsThere were mountains on the MoonJupiter has four moonsSaturn has ringsHe eventually compiled and published his observations in a 1610 work titled The Starry Messenger. Galileo’s work, combined with the previous discoveries of Copernicus and Kepler, left little doubt among the mainstream scientific community that the Ptolemaic model of the universe was incorrect.He also conducted a famous experiment in which he showed Aristotle had been mistaken in his assumption that objects of different weights falling at different rates of speed. Having proven this, he went on to establish an explanation of speed and motion. Galileo also created a thermometer, which permitted more accurate data collection.Galileo’s telescopic drawing of the moon
18Dialogue on the Two Chief Systems of the World Galileo’s major workWritten in 1632Argued in favor of the heliocentric model of the universeGalileo’s masterpiece was Dialogue on the Two Chief Systems of the World, in which he argued in favor of the heliocentric model of the universe. Dialogue was cleverly written as a series of discussions between three individuals over four days:Simplico, a simple-minded scholar, represented the geocentric view of the universe and supported Ptolemy’s and Aristotle’s ideasSagredo, initially a neutral, intelligent laymanSalviati, another scholar, presented the Copernican view of the universe; he also mixed in some of Galileo’s ideas along with criticisms of Simplico’s viewsThrough this literary tool of a staged debate, Galileo argued for the Copernican view of the universe. Readers were left with little doubt about the “correct” view at the end. Although the Dialogue met with a mixed reception at the time because of its controversial nature, the work generally stood up to scientific criticisms for centuries to come.Frontspiece from the Dialogue; from left to right, the figures shown are Aristotle, Ptolemy, and Copernicus
19Galileo vs. the Catholic Church The church condemned heliocentric conceptions of the universeThe Roman InquisitionGalileo’s trialGalileo recants, put under house arrestGalileo’s scientific observations proving that the Earth wasn’t at the center of the universe had vast religious implications. The Catholic Church perceived heliocentric theories as questioning long-held doctrinal teachings about the nature of the heavens. The Church ultimately found it easier to condemn the heliocentric view of the universe as “foolish” and “formally heretical” rather than figure out how it could fit into a religious framework.In 1630, Galileo had received conditional permission from the Vatican to publish the Dialogue. Months after its first printing in 1632, however, Pope Urban VIII ordered a halt to distribution of the book and created a special commission to investigate whether the work was heretical. The commission recommended that Galileo’s case be referred to the Roman Inquisition, which ruled on cases of suspected heresy. Galileo’s trial before the Inquisition tribunal began in April 1633.Galileo defended himself by arguing that while the Church had earlier told him not to hold or believe Copernican theories, it had never told him not to teach about them. The tribunal threatened Galileo with torture, imprisonment, and even burning at the stake if he refused to recant his views; eventually, he succumbed. Sentenced to house arrest due to his fragile health and advanced age, Galileo was forced to recite prayers every day and wasn’t supposed to be allowed visitors, though neither of these were well enforced. In spite of the toll it had taken on him both mentally and physically, Galileo’s battle with the Church didn’t dampen his intellectual curiosity, and he continued to write, research, and publish. The trial had a chilling effect on scientists practicing in Italy and pushed the focus of mainstream science north to places like England and France. It also highlighted the tensions between religion and science.19th-century depiction of Galileo before the Inquisition tribunal
20Sir Isaac Newton (1642–1727)English astronomer, physicist, and mathematicianSynthesized the works of Copernicus, Kepler and GalileoThe PrincipiaConsidered by many to be the greatest figure of the Scientific Revolution, Newton synthesized the works of Copernicus, Kepler, and Galileo in formulating his theories on gravity and motion. After decades of research, he presented the foundation of these theories (along with other observations concerning mathematics and geometry) in the Principia, perhaps the most influential science book ever written. The Principia presented a new view of the world, one expressed in entirely mechanical terms, with Newton portraying the universe as a large clock that operated by a consistent set of rules. The book was well received by the academic community of Europe at the time and his new world view became the accepted paradigm until the atomic age.Legend holds that Newton “discovered” gravity when an apple fell on his head from a nearby tree, although many believed Newton—who loved to tell stories—made the whole thing up.
21Newton’s Laws of Motion Law of Inertia: Argues that bodies in motion tend to stay in motion unless acted on by an outside force. This force can be something viable and obvious or something more subtle like gravity.Fundamental Law of Dynamics: Explains how the velocities of objects change when outside forces are applied. Considered the most important of the three laws of motion.Law of Reciprocal Actions: Posits that for for every action, there is an equal and opposite reaction.The central unifying element for Newton was that motion in the heavens was linked to motion on earth by the law of universal gravity.First Law: Law of InertiaSecond Law: Fundamental Law of DynamicsThird Law: Law of Reciprocal Actions
22Medicine Before the Scientific Revolution Based on traditionThe ChurchIllustration depicting a bloodletting, an accepted medical procedure before the Scientific RevolutionBefore the Scientific Revolution, many practitioners of medicine relied on theories that were centuries old and rarely based on anatomical research or observation. Medical treatments were at best ineffective and at worst lethal. In addition, the Church banned dissection, a practice critical in understanding the human body and how illnesses affect it. In general, the Church viewed sickness not so much as a physical disorder but as a spiritual punishment for sin; correspondingly, human intervention was seen as challenging the will of God.
23Ancient Medicine: Galen (131–201 CE) Greek physicianOn the Elements According to Hippocrates“Bodily humours”Two types of bloodOn the Use of the Parts of the BodyMuch of Galen’s work was based on Hippocrates, the Greek physician often called “the father of medicine.” In On the Elements According to Hippocrates, Galen refined Hippocrates’ ideas on “bodily humours.” The ancient Greeks believed that the human body was made up of four fluids: blood, phlegm, yellow bile, and black bile. An imbalance of these fluids could cause sickness or death. The theory of bodily humours inspired Greek, Roman, and medieval medical cures, including bloodletting (bleeding a patient in order to “draw off” an excess of a certain bodily humour), forced vomiting, and various alchemical potions.Galen also believed that there were different types of blood in the body and two different blood systems: the venus and arterial. Venus blood was created in the liver, while arterial blood was created in the heart. Blood brought “pneuma” or “spirituous air” throughout the body and was eventually used up, so it did not return to its place of origin for circulation. It was not known that the heart played a role in the movement of blood. Rather, doctors believed that the pulsing energy of the arteries themselves caused the blood to move throughout the body.Galen later produced a 17-volume work titled On the Use of the Parts of the Human Body. He based his conclusions in the book on research he had conducted on animals (mainly apes); consequently, On the Use of the Parts of the Human Body contained many errors, especially concerning the internal organs. For all his mistakes, however, Galen’s medical theories remained the standard for over a thousand years.
24Medieval Medicine: The Catholic Church Provided for care of the poor and the sickMinor clerics took on physician-like rolesEventually, university-trained physicians displaced clerical physiciansDuring the Middle Ages, the Catholic Church assumed responsibility for taking care of the poor and the sick. Consequently, the Church also became the acknowledged authority on which medical practices were acceptable. Many lower-ranking clerics took on physician-like roles, since they were usually the ones charged with directly dealing with the sick. Church leadership was uncomfortable with this development because clerics who practiced medicine tended to shirk their religious duties. The Church began to pass canon laws that both regulated and limited the involvement of clergy in the practice of medicine. Eventually with the rise of universities, trained physicians began to replace clerical physicians.Clerics treat a royal patient with leeches
25Andreas Vesalius (1514–1564) Belgian anatomist On the Fabric of the Human BodyCorrected many of Galen’s errorsAndreas Vesalius pioneered the modern study of anatomy and wrote the first complete anatomy text, On the Fabric of the Human Body (De Humanis Corporis Fabrica). Published in 1543, the work consisted of seven volumes illustrated with fine engravings based on Vesalius’ own drawings. He had gathered information for the text largely through the many dissections of human cadavers he had performed. On the Fabric of the Human Body corrected many of Galen’s errors and revolutionized knowledge of human anatomy.
26William Harvey (1578–1657) English physician On the Movement of the Heart and Blood in AnimalsDescribed the functioning of the heart and circulatory systemDisproved Galen’s theoriesIn 1628, English physician William Harvey wrote On the Movement of the Heart and Blood in Animals, a work based on years of observation and dissection of both animal and human subjects. In the book, Harvey argued that blood was pumped through the body by the heart and constantly circulated; he also proved that the same blood flows in both veins and arteries. Harvey’s conclusions disproved Galen’s theories and created a basic model of blood circulation that is still recognized as the standard today.
27Chemistry Joseph Priestley (1733–1804) Antoine Lavoisier (1743–1794) Chemistry as we know it today didn’t really exist until the Scientific Revolution. Modern chemistry began with Robert Boyle, a British scientist who was the first to make a distinction between a chemical element and a chemical compound. He is most famous for Boyle’s Law, which states that the volume of a gas under compression is inversely proportional to the amount of pressure.Another British chemist, Joseph Priestley, was the first to isolate and identify oxygen. He also discovered other gases (including ammonia and carbon monoxide), wrote a book on electricity, and coined the term “rubber.”French scientist Antoine Lavoisier conducted several experiments involving combustion. He discovered not only that substances combine with oxygen when they burn, but also showed that water was made up of hydrogen and oxygen. In addition, he identified 23 other elements and invented a nomenclature (naming system) for chemical elements.Antoine Lavoisier (1743–1794)Robert Boyle (1627–1691)
28Carolus Linnaeus (1707–1778) Swedish botanist Classification and naming of flora and faunaThe Swedish botanist Linnaeus developed a system for the classification and formal naming of all plants and animals by genus and species which is still used today. He also conducted research into hybridization, the process by which two distinct species cross-breed. Though Linnaeus initially theorized that species remained constant and didn’t change, towards the end of his life he did admit the possibility that a new species could arise through hybridization.
29Jean-Baptiste Lamarck (1744–1829) French biologistEarly theory of evolutionPhilosophie ZoologiqueLamarck’s “laws”In his famous work Philosophie Zoologique, French biologist Jean-Baptiste Lamarck proposed an early theory of evolution. He laid out two “laws”: the first stated that changes in an animal or plant’s environment can cause modifications in behavior, which in turn can lead that animal or plant to either make greater or lesser use of a certain body part or structure. These parts or structures then either enlarge or shrink, depending on increased use or disuse. Lamarck’s second “law” posited that these changes to body parts and structures subsequently get transmitted to an organism’s offspring.Largely discredited during his lifetime, Lamarck was later praised by Charles Darwin as having been one of the first to recognize changes occurring in the organic world.
30MathematicsMath symbols for addition, subtraction, multiplication and divisionAnalytical geometry: DescartesCalculus: Newton+The modern signs for mathematical operations were created by Francois Vieta in France in 1603 and were adopted as standard during the Scientific Revolution. In addition, new branches of mathematics arose: René Descartes came up with analytical geometry and Sir Isaac Newton invented calculus, the study of rates of change.-
31New Invention: The Telescope Invented in the NetherlandsGalileoNewtonThe telescope was invented in the Netherlands in the late 16th century. Until Galileo made improvements to it in the early 1600s, it had not really been widely used as a practical tool for scientific observation. Sir Isaac Newton made further refinements in the early 1700s when he invented the reflector telescope, which uses a curved mirror to magnify objects to a much greater degree than a simple glass lens is capable.Illustration of Galileo at his telescope
32New Invention: The Microscope Hans JanssenAnton Van LeeuwenhoekRobert HookeConsiderable scholarship exists tracing the origin of the microscope. The first simple microscopes appeared during the Renaissance, but were limited both in power and in the range of tasks for which they could be used. Around 1590, Dutch spectacle makers Hans Janssen and his son Zacharias began to construct compound microscopes, which used several lenses and produced much greater magnification of objects. In the mid-1600s, another Dutchman named Anton Van Leeuwenhoek developed new methods for grinding and polishing tiny lenses of great curvature which gave magnifications up to 270 diameters, the finest known at that time. He used these lenses to build vastly improved microscopes and make several groundbreaking observations: he was the first to see bacteria, blood corpuscles, and the “life” found in a drop of water. In the 1660s, Robert Hooke of the Royal Society of London improved on Leeuwenhoek’s microscope and performed a series of weekly demonstrations to show the power of the instrument. In 1665, he wrote Micrographia, a finely illustrated compendium of microscopic observations that also used the word “cell” as a biological term for the first time; the book sparked increased public interest in microscopy.Hooke’s drawing of a flea (from Micrographia)A Janssen microscope, c.1600
33New Invention: The Pendulum Clock Invented by Christiaan Huygens, a 17th-century Dutch scientistAllowed scientists to more accurately measure timeGalileo had sketched out a similar design for a pendulum clock in the late 1500s, but it never was built. Huygens’s prime innovation was the balance wheel and spring, which allowed clocks of the era to keep time accurate to within ten minutes a day. Later enhancements in the mid-1700s brought that margin of error down to 10 seconds. Watches and clocks were built in all sorts of shapes and sizes using the pendulum concept, including portable devices that allowed for timing at remote or field locations.Huygens’s design for a pendulum clock
34New Invention: Barometer Invented by 17th-century Italian physicist Evangelista TorricelliThe barometer measures air pressureThe barometer was the brainchild of Evangelista Torricelli, an Italian student of Galileo. Torricelli was trying to create a perfect vacuum and during the course of his experiments, he noticed that atmospheric pressure affected the height to which a fluid would rise in a tube he was using. The barometer’s ability to measure air pressure can be used in weather prediction. High pressure generally predicts moderate weather while low pressure generally predicts storms.Torricelli’s barometer experiment
35New Invention: Thermometer Invented in the 17th century by Santorio Santorio, an Italian scientistFerdinand IIGabriel FahrenheitAnders CelsiusNot surprisingly, Galileo had created a rudimentary thermometer; however, the invention of the thermometer is credited to Santorio Santorio, an Italian noble. He is also credited for proposing the medical use of the thermometer. Santorio’s thermometer was not very accurate because it was an air thermometer, which meant it was unsealed. In 1654, Ferdinand II, the Grand Duke of Tuscany, invented the first sealed thermometer using alcohol as the liquid. In 1714, German-born Dutch instrument maker Gabriel Fahrenheit created a much more accurate thermometer by using mercury instead of alcohol. Fahrenheit also invented the first standard temperature scale, which is used today in the United States. Many other countries use the Celsius scale, which was devised by Swedish scientist Anders Celsius in 1742.Santorio SantorioIllustration depicting Santorio’s thermometer
36New Invention: Mechanical Calculator Invented by Wilhelm Schickard, a 17th-century German inventorGottfried von Leibniz’s “Step Reckoner”Schickard corresponded with Kepler in the 1620s and described a design he had for a “calculating clock” that could perform complex numerical calculations. Schickard’s machine could add, subtract, multiply, and divide. Later in the 17th century, German mathematician Gottfried von Leibniz built upon both Schickard’s model and one created by French mathematician Blaise Pascal to create a “Step Reckoner” that could also do square roots. All these machines were forerunners of modern-day computers.Wilhelm SchickardA 1624 sketch Schickard made of his calculator
37The Significance of the Scientific Revolution Abandonment of ancient and medieval systemsDevelopment of the scientific methodThe EnlightenmentThe most obvious result of the Scientific Revolution was the rejection of ancient and medieval systems in science, astronomy, and medicine. After the Scientific Revolution, many previously accepted theories had been completely disproved or discarded.The methods developed during the Scientific Revolution would fuel discoveries for centuries to come. Basing science more firmly in empiricism made conclusions more consistent, reproducible, and accurate.The Scientific Revolution also set the stage for the Enlightenment. Like the pioneers of the Scientific Revolution, Enlightenment thinkers strove to make conclusions based on observation, logic, and reason, rather than on faith.Though the Scientific Revolution had little immediate impact on society as a whole, its long-term repercussions can still be felt today. Perhaps more important than the specific advances in science, the Revolution represented a shift in worldview: it was an intellectual revolution that changed the way that people saw and interpreted the world around them.