|Objectives | |
|By the end of this lesson, students will be able to: | |
|describe the scientific method and its effect on Western Europe | |
|distinguish between the scientists Copernicus, Kepler, Galileo, Newton, and Harvey and their works | |
|compare the political theories of Hobbes and Locke | |
|explain how science and philosophy influenced one another during the Enlightenment | |
|explain the term enlightened despot, using the model of Frederick II of Prussia | |
|Click here for the course glossary | |
|Click here for a Timeline of The Enlightenment and Scientific Revolution | |
|This lesson discusses European society between 1600 and 1800--an era marked by the power of ideas and rational | |
|thinking. The term Scientific Revolution is used to describe the growing acceptance and influence of the scientific| |
|method and the belief that reason and inquiry can explain and even change the world. The term Enlightenment is | |
|perhaps a more accurate name for this period because it incorporates a variety of intellectual movements that today| |
|we do not consider sciences: philosophy, theology, economics, history, and political theory. | |
|The word scientist did not yet exist in the 1600s. The word science meant no more thanknowledge. For instance, | |
|Isaac Newton is known today for explaining the theory of gravity, explaining optics, and developing calculus. He is| |
|considered one of the greatest scientists in history. Newton, however, called himself a natural philosopher. He saw| |
|all scientific work as part of rational philosophy. | |
|The ideas of this period had and still have great power. The next five lessons will explore the political and | |
|revolutionary impact the Enlightenment had on Europe and the rest of the world. Even today we are living in the | |
|legacy of the Enlightenment. | |
|The Scientific Method | |
|Today the scientific method is understood as a series of five steps that can be repeated continuously. | |
|Observation of phenomena: a scientist observes something that happens and forms a question about it. | |
|Creation of a hypothesis: a scientist thinks up a general explanation that could account for the observed | |
|phenomena. | |
|Prediction of an unobserved event based on the explanation: a scientist deduces from the hypothesis another event | |
|that would occur if the explanation were always true. | |
|Testing of the event: a scientist develops a test that measures the accuracy of the prediction. Often the test | |
|involves an experiment to see if the predicted event actually occurs. The scientist needs to collect data to | |
|evaluate the test. | |
|Conclusion and reassessment of the hypothesis: if the predicted event did not occur, the scientist must either | |
|modify or abandon the hypothesis. If the predicted event occurred, a scientist takes this confirmation as evidence | |
|that the hypothesis is true. | |
|These steps are to be repeated again and again. Conclusions, therefore, are always subject to further testing and | |
|modification. Since the scientific method is a cyclical process, the process never ends. After conclusions are | |
|drawn, new questions almost always arise, starting the cycle over. The conclusion could be refined, changed, or | |
|discarded based on new experiments. | |
|A hypothesis is scientific if it is testable and can be proven true or false. The Greek word for test or try is | |
|empeira. Using this method of tests or experiments is therefore calledempiricism. Any theory or result that can be | |
|tested is called empirical. | |
|Although historians often credit Enlightenment thinkers with the scientific method, a similar experimental method | |
|was in use during the Middle Ages. For instance, Robert Grosseteste and his pupil Roger Bacon explained and used | |
|such methods in England around 1200. Furthermore, some doctors and philosophers in the ancient world used similar | |
|methods. Does the Scientific Revolution really start back then instead of around 1600? | |
|There is some evidence in support of an early start for the Scientific Revolution. The Middle Ages was full of | |
|scientific learning and advancements. Inventions, such as the stirrup and field rotation, relied on some form of | |
|experimentation, and both inventions made society more efficient. Also during the Middle Ages, people eagerly | |
|adopted many earlier inventions that were neglected or unknown to the Roman world: wind and water mills, paper, the| |
|printing press, guns, and cannons. All of these innovations spread rapidly throughout Europe and the surrounding | |
|areas. All of these innovations, however, were different from the developments starting in the 1600s. | |
|In the 1600s, however, thinkers began using new and different hypotheses. The Scientific Revolution constitutes a | |
|break from the Middle Ages in four significant ways. Unlike the natural philosophers of the Middle Ages, | |
|Enlightenment scholars: | |
|emphasized universal laws, | |
|relied on mathematics and mathematical formulas, | |
|benefited from several new and important technologies, and | |
|benefited from a society that was more open to the questioning of authority. | |
|[pic]An engraving from an early math book shows the superiority of Arabic numerals. The picture shows a duel | |
|between the Greek Pythagoras calculating using an abacus and the Medieval philosopher Boethius using the new Arabic| |
|numerals. Gregor Reisch, Margarita Philosophica, vol. IV (1508). | |
|Here is how these four points converged at the end of the Middle Ages and resulted in the Scientific Revolution. | |
|Around the 1600s, thinkers began basing their theories more on universal physical laws, rather than supernatural, | |
|religious, or philosophic ideas. For example, the movement of the planets had been explained as the actions of the | |
|Roman god Mars, the complete perfection of the heavens, or proof of God's power. During the Scientific Revolution, | |
|these explanations were dismissed as scientists developed theories and laws about gravity. | |
|These new laws relied heavily on mathematics. The largest factor in Europe's mathematical revolution was the use of| |
|Arabic numerals and mathematics during the 1200s (the late Middle Ages). The use of the Arabic decimal system made | |
|writing, reading, and calculating numbers much easier than earlier systems like Roman numerals. However, though | |
|they were introduced in the Middle Ages, Arabic numerals did not become the standard in Europe until their use in | |
|printing at the end of the 1400s. Also contributing to Europe's mathematical renaissance was the rediscovery of | |
|Greek mathematicians like Euclid and Archimedes. | |
|The steps in the scientific method require accurate measurement. More precisely, the tools available for accurate | |
|measurement limit the types of problems a scientist can investigate and the kinds of hypotheses a scientist will be| |
|able to test. | |
|During the 1600s, advances in polishing glass led to inventions like the telescope and microscope. Astronomy was | |
|therefore able to advance quickly, thanks to the ability to make accurate observations with telescopes and record | |
|these observations in the new number system. | |
|[pic]These are Copernicus's mathematical observations which supported his theory that the earth revolved around the| |
|sun. This image is from a manuscript in Copernicus's own handwriting. | |
|There were obstacles to the widespread use of the scientific method: the strictness of society and the appeal to | |
|authority. Many thinkers of the late Middle Ages followed traditional authorities such as the Bible, early writings| |
|of church leaders, and the works of the Greek philosopher Aristotle (because his writings supported the teachings | |
|of the church). To most thinkers of the Middle Ages, experimentation was unnecessary. | |
|Lesson 1 described how Renaissance and Reformation scholars challenged the authority of the church. At the same | |
|time, newly rediscovered and printed Greek manuscripts made it clear that other Greek and Roman philosophers | |
|disagreed with Aristotle. In the 1600s, the time was right for questioning authority, performing experiments, and | |
|trusting in the scientific method. | |
|[pic]Vesalius's anatomy book had extremely accurate and beautifully done engravings of the entire body, showing | |
|each stage of dissection. | |
|Medicine and Anatomy | |
|During the Middle Ages, European medicine relied on the study of ancient authorities, such as the writings of Greek| |
|doctors Hippocrates and Galen. Although both Greeks made advances and careful observations in their day, neither of| |
|them practiced dissection. As a result, their theories about many illnesses were completely incorrect. | |
|In 1543, Andreas Vesalius publishedThe Structure of the Human Anatomy, a beautifully illustrated book on the human | |
|body. The benefits of observation and dissection were made clear because Vesalius's work showed how Galen (and | |
|therefore all university teaching in Europe) was incorrect about many structures of the body. Vesalius became | |
|famous and was eventually appointed the court physician to the Hapsburg emperors Charles V and his son Philip II of| |
|Spain. | |
|Despite Vesalius's success, dissections of human corpses remained objectionable to secular and church authorities. | |
|In fact, as recently as 19th century, medical students had to steal buried corpses or use the bodies of executed | |
|criminals. | |
|Despite the views of religious authorities, Enlightenment scholars continued to use experimentation and dissection | |
|to carry knowledge further. Surprisingly, neither Galen nor Medieval medicine knew that veins and arteries both | |
|held blood. In 1628, William Harvey showed how the heart functioned as a pump. It pulled blood in from the veins | |
|and pumped them out to the arteries. Without a microscope to see the capillaries (very small blood vessels), it was| |
|difficult to show that blood from arteries returned to veins. These discoveries were controversial, but gradually | |
|became accepted by the medical community. This new knowledge about the circulatory system did not, however, stop | |
|the dangerous practice of bloodletting. Throughout history, doctors had tried to cure diseases by draining "bad" | |
|blood from sick patients. This dangerous practice continued for another century. | |
|[pic]This diagram from Harvey's work shows that blood in the veins flows only toward the heart. He tied a | |
|tourniquet on an arm to make the veins and their valves clear. Then he pressed blood away from the heart and showed| |
|that the vein would remain empty because valves prevent it from flowing the other way. | |
|Even after dissections and experiments added a wealth of knowledge about the human body, medicine remained | |
|primitive for many years. During the U.S. Civil War in the 1860s, doctors performed surgery in non-sterile | |
|conditions, completely unaware of the germ theory of disease. In many ways, their practices did not dramatically | |
|differ from the case studies of ancient Greek doctors. Despite evidence of their inaccuracy, American and European | |
|doctors read and studied the works of Hippocrates and Galen well into the 19th century. | |
|[pic]In this diagram of Ptolemy's system of epicycles, the planet Jupiter rotates in a circle around a point which | |
|rotates around a point that rotates closer around the earth. This erroneous system accounted for most of the | |
|observed data about the planets. The system was created in order to make the Earth the center of the universe and | |
|to preserve heavenly perfection of perfect circles. | |
|Astronomy: Copernicus, Galileo, and Kepler | |
|In 1543, the same year that Vesalius published his book of anatomy, Copernicus published his book on the | |
|heliocentric theory, De Revolutionibus Orbium Coelestium (or On the Revolutions of the Heavenly Spheres). In this | |
|book, Copernicus sought to prove that the Earth revolved around the Sun, even though most people of his time | |
|thought the Sun revolved around the Earth. Although this book did not generate much controversy when it was first | |
|published, it eventually became the center of the debate between the old world and the new science. | |
|During the Middle Ages, the state of the world and mankind was thought to be directly controlled by God. According | |
|to this idea, the heavens were perfect, and so was the order of the world below (popes, bishops, kings, nobles, | |
|serfs). Entrenched powers felt that questions about the perfect order of the heavens could lead to questions about | |
|the nature of their own power. | |
|Common sense and the Bible seemed to indicate that the Sun revolved around the Earth. Every day we see it rise in | |
|the east and set in the west. It moves and we do not. Stars too seem to rise, set, and rotate around the Earth. | |
|The idea that the heavens above Earth were perfect existed long before Christianity. The Greek philosopher | |
|Aristotle believed in the Earth-centered model. The Greek astronomer Ptolemy devised a system of circles within | |
|circles to describe the motion of the planets. In this system, their orbits were still around the Earth, and still | |
|consisted of perfect circles, although they were in a clumsy system that even Ptolemy did not consider elegant or | |
|accurate. Ptolemy's system could not explain why Mercury was always within 28 degrees of the Sun and why Venus was | |
|always within 47 degrees of the Sun. Still, his system was taught and approved of in Europe for over a thousand | |
|years. | |
|Copernicus's heliocentric theory was not entirely new. Egyptian, Mesopotamian, Chinese, Indian, and Greek | |
|astronomers noticed that planets moved differently from the stars. Careful observations indicated that the planets | |
|did not move in perfect circles around the Earth. | |
|[pic]This diagram shows Kepler's second law of planetary motion. As a planet orbits the sun in an ellipse, it | |
|speeds up as it gets closer to the sun. Equal areas of the ellipse are traveled by the planet in an equal amount of| |
|time. So if area B and area A are equal, then it takes the planet the same time to travel the two arcs. Therefore | |
|it is moving faster around area A (since it covers more distance in the same amount of time). | |
|Many astronomers investigated Copernicus's idea of a universe centered on the sun. In 1609 and 1619, the German | |
|Johannes Kepler published three revolutionary laws about planetary motion. First, he stated that orbits are not | |
|exact circles, but ellipses.Most planetary ellipses are very close to circles, so the diagram here is an | |
|exaggeration. However, these ellipses were a dagger in the heart of the theory of heavenly perfection. | |
|Ellipses are regular mathematic forms and the laws for measuring their area were known to the ancient Greeks. | |
|Kepler connected these mathematical formulas to planetary observations.Kepler's second law stated that the motion | |
|of a planet over a fixed period of time always covers the same area of the ellipse. This law also means that the | |
|planets move faster when they are closer to the Sun. | |
|Kepler's third law was even more complex and a clever use of mathematics. It compared the orbits of two planets, | |
|specifically the time it takes them to orbit the Sun and the planets' average distance from the sun. He showed that| |
|the cube of the ratio of their years (time to orbit the sun) equals the cube of the ratio of their distances from | |
|the sun. It is a curious and beautiful law, but not one with immediate practical applications. Seventy years later,| |
|an even greater mathematical genius, Isaac Newton, would explain that law and many other mysteries of the universe.| |
|[pic]As Kepler published his laws of planetary motion, an Italian professor named Galileo Galilei invented the | |
|first telescope. Within a few years, Galileo made discoveries that supported claims regarding the not-quite-perfect| |
|nature of the heavens. | |
|Galileo's telescope allowed him to see craters and mountains on the moon. He saw sunspots, which blemished the | |
|supposed perfection of the Sun. He discovered four moons orbiting Jupiter--which further proved that not everything| |
|orbited the Earth. He also showed that the brightness and phases of the planet Venus were consistent with | |
|Copernicus's heliocentric system but not with a system that had Earth as its center. | |
|Here is Galileo's description of the moon and the Milky Way observed with a telescope. Notice how Galileo uses the | |
|word philosophers to refer to people we would call scientists: | |
|The moon is not perfectly smooth, free from inequalities, and exactly spherical, as a large school of philosophers | |
|considers with regard to the moon and the other heavenly bodies. On the contrary, it is full of inequalities, | |
|uneven, full of hollows and bulges, just like the surface of the earth itself, which is varied everywhere by lofty | |
|mountains and deep valleys... | |
| | |
|The next object which I have observed is the essence or substance of the Milky Way. By the aid of a telescope, | |
|anyone may behold this in a manner which so distinctly appeals to the senses that all the disputes which have | |
|tormented philosophers through so many ages are exploded by the irrefutable evidence of our eyes, and we are freed | |
|from wordy disputes upon the subject. For the galaxy is nothing else but a mass of innumerable stars planted | |
|together in clusters. Upon whatever part of it you direct the telescope, at once a vast crowd of stars presents | |
|itself to view. Many of them are rather large and extremely bright, but the number of small ones is quite beyond | |
|determination. | |
|Galileo Galilei The Starry Messenger 1610 | |
|Galileo's observations of the heavens were part of a larger agenda; he hoped to discover a rational account of all | |
|motion. Eventually, his work would form the basis for what we call physics today. Galileo discovered inertia, the | |
|idea that bodies at rest will remain at rest and bodies in motion will remain in motion until another force | |
|interacts with them. If you throw an object, it will keep going forever, unless another force interacts with it. On| |
|Earth, gravity and friction from the air would stop a thrown object relatively quickly, but this is not the case in| |
|outer space. Galileo therefore showed that Aristotle was wrong about the basic facts of motion. | |
|Galileo also discovered mathematical rules about physics. Many of his experiments were with objects subjected to a | |
|constant force (such as gravity). He showed that the total distance covered by a falling object, starting from | |
|rest, is proportional to the square of the time falling. Galileo's measurements and mathematical laws (and Kepler's| |
|too) show the importance of mathematics to the new sciences. | |
|The Catholic Church did not tolerate Galileo's open acceptance of Copernicus's theories.Both Catholic and | |
|Protestant church authorities banned books that advocated heliocentric systems, and occasionally they advocated | |
|burning the authors alive as heretics. In 1616, the Inquisition forbade Galileo from holding or advocating the | |
|heliocentric theory. However, in 1623, Galileo thought that these terms would allow him to write a treatise | |
|discussing both systems, especially since the new pope was one of his personal friends. | |
|Galileo was wrong. The pope's Inquisition summoned the 69 year-old man to Rome, where he was shown the instruments | |
|of torture. The burning alive of Giordano Bruno in 1600 for teaching unofficial doctrine about the heavens was | |
|already a clear warning. Galileo confessed, admitted his mistakes, and was sentenced to life imprisonment. He lived| |
|out the last nine years of his life under house arrest, forbidden to meet people socially or to publish. | |
|Isaac Newton and the Royal Society | |
|Histories of science and technology tend to be discussions of singular genius: one person who is a giant in a field| |
|of research or in many fields. However, a genius needs a receptive environment, as the fate of Galileo shows. | |
|In the 1640s, a group of people got together in London to discuss new scientific discoveries. We can see that the | |
|terms science, scientist, and scientific were not yet invented, because the group had difficulty describing exactly| |
|what they were discussing. The closest words, philosophy or even natural philosophy, were too inclusive. So they | |
|said that they would study everything except for religion and politics. In 1662, this group was officially | |
|incorporated as the Royal Society of London for Improving Natural Knowledge, or simply "the Royal Society." | |
|Here is a description by an eyewitness of the first meetings of the group. Note that he refers to the ban on | |
|religion and politics (theology and the affairs of state): | |
|About the year 1645, while I lived in London,...I had the opportunity of being acquainted with diverse worthy | |
|persons, inquisitive into natural philosophy, and other parts of human learning; and particularly of what has been | |
|called theNew Philosophy, or Experimental Philosophy. We did...meet weekly in London on a certain day, to treat and| |
|discourse of such affairs...Our business was (precluding matters of theology and state affairs), to discourse and | |
|consider ofPhilosophical Enquiries, and such as related thereunto: as physic, anatomy, geometry, astronomy, | |
|navigation, statics, magnetics, chemics, mechanics, and natural experiments; with the state of these studies, as | |
|then cultivated at home and abroad. We then discoursed of the circulation of the blood, the valves in the veins, | |
|the venae lactae, the lymphatic vessels, the Copernican hypothesis, the nature of comets and new stars, the | |
|satellites of Jupiter, the oval shape (as it then appeared) of Saturn, the spots in the sun, and its turning on its| |
|own axis, the inequalities and selenography of the moon, the several phases of Venus and Mercury, the improvement | |
|of telescopes, and grinding of glasses for that purpose, the weight of air, the possibility, or impossibility of | |
|vacuities, and nature's abhorrence thereof, the Torricellian experiment in quicksilver, the descent of heavy | |
|bodies, and the degrees of acceleration therein; and diverse other things of like nature. Some of which were then | |
|but new discoveries, and others not so generally known and embraced, as now they are, with other things | |
|appertaining to what has been called The New Philosophy. | |
|from John Wallis, Account of Some Passages of his Life, 1700. Charles W. Colby, ed., Selections from the Sources of| |
|English History, (London: Longmans, Green & Co., 1920), pp. 196-199. | |
|It is clear that these scholars had a variety of interests. From antiquity up until the 20th century, it was | |
|possible for an educated person to follow advances in many if not all branches of science. Note that many of these | |
|topics were Galileo's discoveries (the satellites of Jupiter, the shape of Saturn, sunspots, the phases of Venus, | |
|and the acceleration of heavy bodies). | |
|Around the same time that the Royal Society first met, Isaac Newton was born in northern England. After he | |
|graduated from college in 1665, he was forced to stay at home for a couple of years because a plague struck all of | |
|England. During his time at home, Newton invented calculus and began working on the two subjects to which he would | |
|dedicate his life: optics and gravitation. | |
|Newton might never have developed his ideas and worked them out into a published form if he did not have a | |
|community of scholars in the Royal Society. He regularly presented his results to the Society and even became its | |
|president from 1703 until his death in 1727. This community did not always agree with Newton. In fact, many of his | |
|papers were responses to disputes that he had with other scholars. Newton's masterpiece, The Mathematical | |
|Principles of Natural Philosophy, was published in 1687 in part as a refutation of the French scholar René | |
|Descartes. Science is often advanced by this type of healthy competition. | |
|Newton's work on optics explained mysteries which had puzzled scholars for centuries. He explained how prisms | |
|separate white light into its component colors, and how they can restore the colors back into white light. He | |
|explained how raindrops in the air act as prisms to create a rainbow. Newton did not, however, realize that the | |
|prism effect was due to the wave-like nature of light. | |
|[pic]This is an example of interpolation in Newton'sPrincipia. By writing in Latin, Newton reached the European | |
|scientific community, but the Principia would be one of the last influential books written in that language. | |
|Although Newton had invented calculus, he preferred using geometry instead in the Principia. This method was far | |
|more difficult, but it was more generally accepted. Ironically, Archimedes had invented calculus almost 2000 years | |
|before Newton, but the manuscript with this invention was first recovered in the 1900s. Archimedes did not use | |
|calculus in his formal proofs either, but stuck to the rules of geometry. | |
|The Mathematical Principles of Natural Philosophy is better known by its Latin title, the Principia Mathematica. | |
|Along with an explanation of prisms, the Principiaalso explained the fundamentals of physics: the laws of motion | |
|and the laws of gravity. | |
|Newton showed how the same force (gravity) controlled the orbits of the planets and moons as well as the actions of| |
|smaller objects on Earth. He also discovered that the force of gravity between two objects increases in proportion | |
|to their mass. The power of gravity grows weaker depending on the square of the distance between the two objects. | |
|This formula provided the answer to the 70 year-old mystery of Kepler's third law of planetary motion. | |
|The Principia was seen by scholars and intellectuals in Newton's day as proof of the scientific method. The world, | |
|it seemed, could be accurately and beautifully described with mathematics. The descriptions could be tested and | |
|proved by observation and experiment. | |
|Although Newton is now considered one of the greatest scientists in history, it is useful to remember that his life| |
|was not exclusively devoted to rational science. Newton and Kepler both shared a mathematical fascination with | |
|mysticism and numerology (although Newton was careful to keep it separate from his scientific publications). | |
|Newton also had a lifelong interest in alchemy, the almost magical art of chemical transformations. Many of his | |
|papers reveal his belief in magic and the occult. Although we now know that alchemy and magic were not productive | |
|avenues of research, the division between them and science was not so clear in Newton's day. Think about the idea | |
|of gravity--a mysterious, invisible force that exists everywhere. It affects small and large bodies on earth and | |
|keeps planets in motion. It is inescapable, yet we barely notice it. This powerful force of gravity could easily | |
|seem like a form of magic. | |
|Enlightenment Philosophers | |
|The dividing line between scientific inquiry and other types of knowledge remains unclear even today. For example, | |
|consider history. The study of history today combines a scientific concern (with measurable, verifiable data) and | |
|philosophical questions of value and importance. As scientists like Kepler and Newton demonstrated the power of | |
|rationality, a whole generation of thinkers became eager to use such methods in their own fields of knowledge. | |
|Lesson 1 discussed how Erasmus applied the scientific method to the study of religion. He examined different | |
|manuscripts of the Bible and used reason to compare them. During the Enlightenment, ambitious scholars and | |
|mathematicians were trying to use reason to prove the existence of God, the superiority of the Christian faith, and| |
|the meaning of human existence. The French mathematicians and philosophers Blaise Pascal and René Descartes are two| |
|notable examples. | |
|In the following passage, Descartes uses reason to try to answer two of the central problems of philosophy: the | |
|nature of existence and whether anything about existence can be known. | |
|I thought that...I ought to reject as absolutely false all opinions where I could suppose the least ground for | |
|doubt, in order to determine whether, after that, there remained anything in my belief that was completely certain.| |
|So, seeing that our senses sometimes deceive us, I was willing to suppose that nothing really existed as our senses| |
|presented to us. And because some men make mistakes in reasoning, and fall into error, even on the simplest matters| |
|of geometry, I, convinced that I was as open to error as any other, rejected as false all the reasonings I had | |
|accepted as proofs. Finally, when I considered that the very same thoughts which we experience when awake may also | |
|be experienced when we are asleep, while there is at that time not one of them true, I supposed that all the | |
|thoughts that had ever entered into my mind when awake, had in them no more truth than the illusions of my dreams. | |
|But immediately upon this I observed that, while I wished to think that all was false, it was absolutely necessary | |
|that I, who thought that way, should nevertheless exist. And as I observed that this truth, "I think, therefore I | |
|am" [in Latin: COGITO ERGO SUM], was so certain and of such evidence that no ground of doubt, however extravagant, | |
|could be alleged by the skeptics capable of shaking it, I concluded that I might, without hesitation, accept it as | |
|the first principle of the philosophy I was looking for. | |
|René Descartes, Discourse on the Method of Rightly Conducting Reason and Seeking Truth in the Sciences, Part IV. | |
| | |
|Descartes points out that our senses can deceive us, so we cannot rely on them. He points out that our reason can | |
|deceive us, so we cannot rely on it. And our thoughts deceive us, so we cannot trust them. How so? Thoughts deceive| |
|us, for example, in dreams, or under the influence of alcohol or drugs. How can one know if the world we are | |
|experiencing now is not a dream or a fake creation? The movie The Matrix (1999) was based on this premise. | |
|Note that Descartes is arguing against experience and observation, since the senses can deceive us. His philosophy | |
|contradicts the scientific method as described above. In addition, many areas of research, such as theology and | |
|moral philosophy, cannot be researched using experiments. | |
|Other writers explored the nature of human societies. They investigated the nature of government and politics. What| |
|is the best way to arrange a country? If the power of God was not needed to move the planets around, was God's hand| |
|really the force that shaped governments here on Earth? Suddenly, the divine right of kings was called into | |
|question. | |
|An English philosopher, Thomas Hobbes, proposed an answer. He started with observations of human emotions and | |
|desires and studied examples from history. After careful consideration of his many observations, he reasoned that | |
|the best and only secure form of government is the rule of an absolute monarch. Without a supreme central power, | |
|nobles and other people will constantly fight: | |
|Hereby it is manifest that during the time men live without a common power to keep them all in awe, they are in | |
|that condition which is called war; and such a war as is of every man against every man....[M]en live without other| |
|security than what their own strength and their own invention shall furnish them withal. In such condition there is| |
|no place for industry, because the fruit thereof is uncertain: and consequently no culture of the earth; no | |
|navigation, nor use of the commodities that may be imported by sea; no commodious building; no instruments of | |
|moving and removing such things as require much force; no knowledge of the face of the earth; no account of time; | |
|no arts; no letters; no society; and which is worst of all, continual fear, and danger of violent death; and the | |
|life of man, solitary, poor, nasty, brutish, and short. | |
|Thomas Hobbes, The Leviathan, (1651) chapter 13. | |
|Hobbes's work was powerful and influential. It remains well argued and eloquently written--almost scientific. To | |
|summarize the above excerpt, without a powerful king to keep the peace, the life of a common man would be poor, | |
|nasty, brutish, and short. All business, all laws, all peace were thanks to an absolute monarch like Peter in | |
|Russia or Louis in France. | |
|Note that Hobbes does not say that the power of kings is based upon the will of God. Rather, the rights of kings | |
|are derived from the laws of human nature. People are, by nature, greedy and uncivilized; they need structure. | |
|Additionally, some people are naturally weaker than others; they will need the protection of those who are | |
|stronger. Certainly, it is only rational and right for the stronger to rise to the challenge. Thus, the right of | |
|kings is based partially on brute force and partially on logic and human nature. Most importantly, although Hobbes | |
|supported the right of kings, his work removed God and divine right. | |
|Another English philosopher, John Locke, questioned the idea of monarchy entirely. He argued that the power to rule| |
|did not come from God or human nature, but from the consent of the people who are ruled. Like Hobbes, Locke saw | |
|that the state of nature was dangerous and uncertain for humans. Unlike Hobbes, Locke did not see the answer in | |
|absolute monarchy, but rather the social contract. Locke argued that throughout history, humans had willingly come | |
|together and formed societies through the forging of contracts. | |
|According to Locke, nature shows that humans have the right to life, to liberty, and to property. They agree to | |
|give up some liberty and property in return for the security that a government gives them. If the government takes | |
|too much of either, humans have a right to replace the government. | |
|The reason why men enter into society, is the preservation of their property; and the end why they choose and | |
|authorize a legislative, is, that there may be laws made, and rules set, as guards and fences to the properties of | |
|all the members of the society, to limit the power, and moderate the dominion, of every part and member of the | |
|society: for since it can never be supposed to be the will of the society, that the legislative should have a power| |
|to destroy that which every one designs to secure, by entering into society, and for which the people submitted | |
|themselves to legislators of their own making; whenever the legislators endeavor to take away, and destroy the | |
|property of the people, or to reduce them to slavery under arbitrary power, they put themselves into a state of war| |
|with the people, who are thereupon absolved from any farther obedience, and are left to the common refuge, which | |
|God hath provided for all men, against force and violence. Whensoever therefore the legislative shall transgress | |
|this fundamental rule of society; and either by ambition, fear, folly or corruption, endeavor to grasp themselves, | |
|or put into the hands of any other, an absolute power over the lives, liberties, and estates of the people; by this| |
|breach of trust they forfeit the power the people had put into their hands for quite contrary ends, and it devolves| |
|to the people, who have a right to resume their original liberty, and, by the establishment of a new legislative, | |
|(such as they shall think fit) provide for their own safety and security, which is the end for which they are in | |
|society. | |
|John Locke, The Second Treatise on Government (1690), chapter 19, section 222. | |
|In other words, if the government tries to take away life, liberty, or property, the people have a right to depose | |
|the government. The next lesson will examine the English Civil Wars that influenced both Hobbes and Locke. The next| |
|lesson will also examine the American Revolution that was in part inspired by Locke's ideas. The intellectual | |
|impact of Locke's ideas can still be felt today in current debates about human rights and civil liberties. | |
|Voltaire and Frederick II | |
|[pic]Voltaire and the music composer Rameau, plot a new musical play. The artist has given Voltaire a mischievous | |
|grin, as though he were planning another outrage. | |
|The French writer Voltaire (the pen name of François Marie Arouet) is the last and best example of the intellectual| |
|movement of the Enlightenment. Voltaire studied problems in science and wrote and published a French summary of | |
|Newton's ideas. He wrote many history books, short novels, and plays. His contemporaries knew him as a poet and as | |
|a philosopher. | |
|Voltaire's wit and writings often got him into trouble. In 1726, at the age of 32, he made a joke at a French | |
|noble's expense. The noble, rather than condescend to confront Voltaire himself, paid some hired thugs to beat him | |
|up. Rather than arrest the people who ordered and carried out the beating, the authorities threw Voltaire in the | |
|infamous Bastille prison in Paris. This was not the first time that Voltaire's wit had landed him in jail or | |
|inspired someone to hire a mob to beat him up. | |
|To escape the oppressive environment of France, Voltaire went to England. He observed and wrote about the freer | |
|atmosphere in science and politics there. His writings about England, including material about Newton and Locke, | |
|were banned and burned in France. | |
|Voltaire also had enemies in the Catholic Church. Unlike most other Enlightenment thinkers, Voltaire did not | |
|consider himself a Christian and openly mocked established religions--Christianity in particular. He therefore | |
|spent many years in Protestant countries, where he also succeeded in offending political and religious authorities.| |
|In addition to mere mockery, Voltaire also used science to criticize organized religion, as can be seen in this | |
|entry in his Philosophical Dictionary: | |
|SECT: Every sect, in whatever sphere, is the rallying point of doubt and error. Scotist, Thomist, Realist, | |
|Nominalist, Papist, Calvinist, Molinist, Jansenist, are only pseudonyms. There are no sects in geometry; one does | |
|not speak of a Euclidian, an Archimedean. When the truth is evident, it is impossible for parties and factions to | |
|arise. Never has there been a dispute as to whether there is daylight at noon. The branch of astronomy which | |
|determines the course of the stars and the return of eclipses being once known, there is no more dispute among | |
|astronomers. In England one does not say--"I am a Newtonian, a Lockian, a Halleyan." Why? Those who have read | |
|cannot refuse their assent to the truths taught by these three great men. | |
|Voltaire, "sect," Philosophical Dictionary (1764). | |
|Voltaire's Philosophical Dictionary offers definitions with a bias and some dry humor. Here the definition of sect | |
|contrasts Christian theology and philosophical schools with pure science. Voltaire mocks denominations such as | |
|Calvinists or Catholics ('Papist') by saying that they are simply collections of doubts and errors. | |
|In 1754, Voltaire bought a house on the outskirts of Geneva, in Calvinist Switzerland. Later he bought an estate | |
|just inside the borders of France. This way he could head across the border to Switzerland in a hurry if he had to.| |
|Many of Voltaire's books were published in Switzerland or Belgium and illegally imported into France. | |
|Before going to Geneva, Voltaire accepted an invitation from Frederick II, the king of Prussia, to spend time at | |
|his court. As a young prince, Frederick II was fascinated by Enlightenment philosophy and had corresponded with | |
|Voltaire. He even wrote a reply to Machiavelli's The Prince, arguing against the amoral philosophy of that work. | |
|Frederick wrote essays and poetry in French, composed and performed music, and attempted to be a well-rounded | |
|Enlightenment intellectual. | |
|In this respect, Frederick II was similar to Peter I of Russia. Both kings gained the reputation of being | |
|enlightened despots (or "enlightened monarchs"). Both kings were impressed with the new sciences, new philosophies,| |
|and new technologies of the Enlightenment. Both kings tried to use science and business to increase their personal | |
|power and the powers of their own countries. | |
|Voltaire and Frederick II were two strong personalities and did not mesh together well. Voltaire could not hold | |
|back from his desire to make fun of authority. Frederick, despite his enlightened interests, insisted that his | |
|authority be absolute. After a few years, Voltaire left Prussia for Geneva, Switzerland. So ended the collaboration| |
|of two stock characters in Enlightenment Europe: the critical philosopher and the enlightened despot. | |
|The Growth of Prussia | |
|By the time Frederick II ascended the throne, Prussia had become an influential power both culturally and | |
|politically. This section examines Prussia's rapid and strategic rise to power. | |
|[pic]Although Frederick II mainly spoke French, Prussia was a kingdom in the East of Germany. Parts of Prussia were| |
|within the Holy Roman Empire, but large sections of it were east of the empire. As a result, the Prussian king | |
|became more independent and more powerful than the other German kingdoms. | |
|The Thirty Years' War (Lesson 3) also contributed to the growth of Prussian power and military strength. During and| |
|after the war, Prussian rulers realized that a large standing army could help them win allies and power. A | |
|"standing army" is an army that is trained and always ready. At the time, European armies were usually only called | |
|upon when needed. The relatively small Prussia could provide a skilled fighting force to the larger kingdoms of | |
|France, Sweden, Russia, Austria, or to the Holy Roman Emperor. In return for fighting others' battles, the | |
|Prussians were granted territories in the peace treaties. | |
|Frederick II's father, Frederick Wilhelm I, built up Prussia in this manner. He also made the army the center of | |
|the Prussian state. Tax collection and other branches of the government were performed by the army. Frederick | |
|Wilhelm I took pride in creating military discipline in both the army and in the government bureaucracy. Even | |
|today, Germans from Prussia have a reputation for efficiency and order. | |
|Frederick II continued his father's practices and embarked on a series of wars with surrounding powers, primarily | |
|Austria to the south. Although Frederick II's army was not always victorious, his diplomatic skills allowed him to | |
|acquire large amounts of land during the peace-making process. By the end of his reign, Prussia had become one of | |
|the great European powers. | |
|Both Frederick Wilhelm I and Frederick II wanted to achieve the prestige of Louis XIV of France and Peter I of | |
|Russia. Although the army was the center of their energies, finances, and government, they realized that the fame | |
|of the Prussian state depended on culture too. They established the Prussian Academy of Science and recruited | |
|world-famous philosophers, mathematicians, and scientists. They founded a world class library and a museum. Such | |
|achievements first established Berlin as a world capital. | |
|In some ways, Berlin was similar to the other new Enlightenment city, Saint Petersburg. Both cities housed an | |
|intellectual class very different from the inhabitants of the surrounding countryside. In Prussia, as in Russia, | |
|feudalism still dominated. Outside the capital, thousands of serfs worked the estates of nobles. Likewise, the | |
|social and political changes in both Russia and Prussia were ordered by the rulers and had minimal impact on the | |
|rest of society. Additionally, both Prussia and Russia lacked the middle class, trade, financial systems, and | |
|infrastructure of the societies they tried to imitate (the Netherlands, England, or the cities of the German | |
|Hanseatic League). | |
|The Prussian kingdom eventually became famous for both its army and its culture. In fact, a century later, Germany | |
|would be united under the Prussian king. This dual legacy of culture and warfare would cast a long shadow over | |
|united Germany and the 20th century. | |
|Lesson Recap | |
|This lesson discussed how the convergence of several key cultural and technological advancements spurred the | |
|Scientific Revolution and the Enlightenment. In some ways, this era can be seen as an extension of the intellectual| |
|energies of the Renaissance. Every aspect of the world and humanity was fair game for the intellect, and not using | |
|one's intellect to address a problem was either due to fear or immaturity: | |
|"Enlightenment" is one's departure from self-imposed (intellectual, philosophical and spiritual) immaturity. This | |
|immaturity can be defined as the inability to use one's own intellect without the direction of another. It is | |
|self-imposed if its cause is not the lack of intelligence or education, but lack of determination and courage to | |
|think without the direction of another. "Sapere aude! Have the courage to use your own intellect!" is therefore the| |
|motto of the Enlightenment. | |
|Immanuel Kant, An Answer to the Question: What is Enlightenment? (1783). | |
|During previous times of change and discovery, scholars who questioned the basic nature of society and the universe| |
|found themselves on the wrong side of church officials and political leaders. Those trying to champion new ideas | |
|that the church didn't like might be imprisoned, like Galileo, or tortured and killed, like Bruno. | |
|As the above quote suggests, the Enlightenment was much more intellectually free than previous eras. It was | |
|characterized by a broad spirit of inquiry and healthy intellectual competition. The Royal Society, for instance, | |
|could never have existed during the Middle Ages. The fact that Newton was celebrated, rather than condemned, also | |
|signifies a cultural change from the Middle Ages. | |
|Despite the freedom of the Enlightenment, scholars bucked the established powers at their own peril. Voltaire was | |
|not the only Enlightenment thinker jailed for annoying powerful nobles. Though Frederick II and Peter I initially | |
|welcomed Enlightenment scholars to their courts, the pleasant relationship between them evaporated when those | |
|scholars challenged the basis of the rule of kings. The tension between the intellectual elite, the middle class, | |
|and the powerful aristocracy are documented in the next several lessons. | |
|Click here for a Timeline of The Enlightenment and Scientific Revolution | |
|Questions for Essays and Discussion | |
|At least one of the following essay questions will appear in the submission for this lesson. | |
|1. Why did religious and political authorities find the heliocentric model of the universe to be so objectionable? | |
| | |
|2. What are the five steps in the scientific method? | |
|3. Why did most Medieval philosophers and scientists feel that experimentation was unnecessary? | |
|4. Compare and contrast the careers of Galileo Galilei and Isaac Newton. What discoveries did each make? How were | |
|their methods similar or different? How were both received by the religious and political authorities of the day? A| |
|complete answer will include an assessment of the political and cultural climate in which each thinker lived. | |
| | |
|5. Explain how the Scientific Revolution influenced Enlightenment thinkers in other disciplines. You should mention| |
|at least two of the following thinkers and topics: divine right of kings, empiricism, Vesalius, Descartes, Hobbes, | |
|or Voltaire. | |
|Further Reading |
|I. Kramnick, ed., The Portable Enlightenment Reader, Harmondsworth, UK: Penguin, 1995. |
|J. I. Israel, Radical Enlightenment: Philosophy and the Making of Modernity 1650-1750, NY: Oxford University Press, USA, 2002. |
|T. L. Hankins, Science and the Enlightenment, Cambridge, UK: Cambridge University Press, 1985. |
|J. Henry, The Scientific Revolution and the Origins of Modern Science, NY: Palgrave Macmillan, 2002. |
|K. Ferguson, Tycho and Kepler: The Unlikely Partnership That Forever Changed Our Understanding of the Heavens, NY: Walker & Co., |
|2004. |
|G. Ritter, Frederick the Great: A Historical Profile, Berkeley, CA: University of California Press, 1975. |
|R. Pearson, Voltaire Almighty: A Life in Pursuit of Freedom, NY: Bloomsbury USA, 2005. |
|Click here for the course glossary |
|Click here for course timelines |