Brief History of Modern Science - PowerPoint PPT Presentation

brief history of modern science n.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
Brief History of Modern Science PowerPoint Presentation
Download Presentation
Brief History of Modern Science

play fullscreen
1 / 88
Brief History of Modern Science
124 Views
Download Presentation
emmly
Download Presentation

Brief History of Modern Science

- - - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

  1. Brief History of Modern Science • Discovery - A new method of acquiring knowledge was invented by a series of European thinkers from 1500 to 1700. Among these thinkers are Copernicus, Galileo, Descartes, Kepler, and Newton • Definition of Science- A special method and knowledge executed by practitioners of science called scientists.

  2. Meaning of Science • Science is practiced byspecially trained people with a specific world view. Scientists try to be objective, non-sentimental, unemotional, honest, and unbiased • Scientists work in laboratories where conditions are carefully controlled. • Scientists report their findings in peer-reviewed journals to other scientists • Scientists do not claim more than what they can prove

  3. Philosophical Foundations of Science Originated in the 17th century • Science removed animism as a physical explanation. Greek philosophers thought movement was a sign of life. Planets were moved by angels. Newton’s 1st law of motion changed this attitude. • Science changed man’s position from the center of the universe to its periphery. Man’s place in the universe was seen as minor.

  4. Aristotelian Science Theory of Matter Matter stuff out of which things are made In sublunary world (below the moon) there are four elements or essences: earth, water, air, and fire. These four elements never found pure always mixed. Heavy things made out of earth Light things made mix of water,air, and fire

  5. Aristotelian Science • Above sun, planets are stars imbedded in the crystalline sphere • The crystalline sphere made out of pure quintessence ( 5th essence) • Different laws pertain the sublunary world than to the world above the moon

  6. Aristotelian Science • Motion • Natural state of all sublunary things is rest • All objects seek rest • Earth, Air, and water seek down for rest • Fire seek rest upward • Bodies seek the grave, the souls seek heaven

  7. Aristotelian Science Motion • Two kinds of motion -- violent and natural • Things move because they’re pulled or pushed • Sun, planets, and stars move in uniform, circular motion • Circles are ideal and circular motion is an aspect of quintessence. • Earth is at center of Universe

  8. Archimedes (287-212 BCE ) Sicilian geometrician who calculated an accurate value for pp, demonstrated the relationship between the volume of spheres and cylinders, discovered methods for determining the center of gravity of plane figures, and provided a foundation for the science of hydrostatics. Archimedes also invented many ingenious machines, including a pump for raising water, effective levers and compound pulleys, and a mechanical planetarium. He died defending Syracuse against a Roman seige during the second Punic war.

  9. Ptolemy & Epicycles more accurate measurement required more epicycles

  10. Thomas Aquinas (1224-1274 ) • Although matters of such importance should be accepted on the basis of divine revelation alone, Aquinas held, it is at least possible (and perhaps even desirable) in some circumstances to achieve genuine knowledge of them by means of the rigorous application of human reason. As embodied souls ( hylomorphic composites ), human beings naturally rely on sensory information for their knowledge of the world. Reading hint: Although the rigidly formal structure of the Summa articles can be rather confusing to a modern reader, the central portion beginning with the words, " I answer that ..." is always a direct statement of Aquinas's own position.

  11. Roger Bacon • Bacon, Roger (1214-1292 )English philosopher who translated many Aristotelean treatises from Arabic into Latin. Although passionately interested in alchemy and magic, Roger defended reliance upon mathematics and experimental methods for the improvement of human knowledge generally and theological understanding in particular in the Opus Maius (Greater Work ) (1267) { at Amazon.com } and On Experimental Science (1268). His novel educational doctrines were supposed to violate the condemnation of 1277 , and much of Roger's later work, including the Compendium Studii Theologiae (1292) was suppressed.

  12. Roger Bacon Bacon’s advice: To study Natural Philosophy, use; “External experience, aided by instruments, and made precise by mathematics.”

  13. Roger Bacon: “The result of all true philosophy is to arrive at a knowledge of the creator through knowledge of the created world” “He who wishes to rejoice without doubt in regard to the truths underlying phenomena must know how to devote himself to experiment. For authors write many statements, and people believe them through (deductive) reasoning, which they formulate without experience. Their reasoning is wholly false” (Opus Majus)

  14. Deductive and Inductive Reasoning A deductive argument is one in which it is claimed that it is impossible for the premises to be true but the conclusion false. Thus, the conclusion follows necessarily from the premises and inferences. In this way, it is supposed to be a definitive proof of the truth of the claim (conclusion). Here is an example: 1. All men are mortal. (premise) 2. Socrates was a man. (premise) 3. Socrates was mortal. (conclusion) As you can see, if the premises are true (and they are), then it simply isn't possible for the conclusion to be false. An inductive argument is one in which the premises are supposed to support the conclusion in such a way that if the premises are true, it is improbable that the conclusion would be false. Thus, the conclusion follows probably from the premises and inferences. Here is an example: 1. Socrates was Greek. (premise) 2. Most Greeks eat fish. (premise) 3. Socrates probably ate fish. (conclusion)

  15. Deductive and Inductive Reasoning inductive The meerkat is closely related to the suricat The suricat thrives on beetle larvae Therefore, probability the meerkat thrives on beetle larvae

  16. Deductive and Inductive Reasoning deductive The meekat is a member of the mongoose family All members of the mongoose family are carnivores Therefore, it necessarily follows that the meerkat is a carnivore mongoose cobra

  17. Inductive Mathematical Reasoning Find a General Rule for the Number series: 0, 2, 8, 18, 32, 50, 72….. Explain the Fibonacci Series: 1, 2, 3, 5, 8, 13, 21, 34,…… Stable Atomic Nuclei have the following number of nucleons (proton and neutrons): 2, 8, 20, 28, 50, 82, 126, … What is the next member in the series?

  18. Abusive ad hominem Accent Ambiguity (index) Amphiboly Age, Appeal to Authority, Appeals to (4 types) Authority, Legitimate Appeal to Ad Hominem (5 types) Begging the Question Circumstantial ad hominem Complex Question Composition Correlation vs. Causation Division Emotion and Desire, Appeals to (5 types) Equivocation Unqualified Authority, Appeal to False Dilemma Flatter, Appeal to Force / Fear, Appeal to (Argumentum ad Baculum) Novelty, Appeal to No True Scotsman Numbers, Appeal to Money, Appeal to Oversimplification and Exaggeration Pity, Appeal to (Argumentum ad Misercordiam) Poisoning the Well Poverty, Appeal to Presumption Quantifier Fallacy Quoting out of Context Reification / Hypostatization Fallacies of Relevance (index) Scope Fallacy Suppressed Evidence Tradition, Appeal to Tu Quoque (two wrongs don't make a right Genetic Fallacy Illicit Observation Logical Fallacieshttp://www.intrepidsoftware.com/fallacy/toc.php

  19. Logical Fallacies • Straw Man • Definition: • The author attacks an argument which is different from, and • usually weaker than, the opposition's best argument. • Examples: • (i) People who opposed the Charlottown Accord probably just • wanted Quebec to separate. But we want Quebec to stay in • Canada. • (ii) We should have conscription. People don't want to enter • the military because they find it an inconvenience. But they • should realize that there are more important things than • convenience. • Proof: • Show that the opposition's argument has been • misrepresented by showing that the opposition has a stronger • argument. Describe the stronger argument.

  20. Logical Fallacies • Coincidental Correlation • (post hoc ergo propter hoc ) • Definition: • The name in Latin means "after this therefore because of this". • This describes the fallacy. An author commits the fallacy when • it is assumed that because one thing follows another that the • one thing was caused by the other. • Examples: • (i) Immigration to Alberta from Ontario increased. Soon • after, the welfare rolls increased. Therefore, the increased • immigration caused the increased welfare rolls. • (ii) I took EZ-No-Cold, and two days later, my cold • disappeared. • Proof: • Show that the correlation is coincidental by showing that: (i) • the effect would have occurred even if the cause did not • occur, or (ii) that the effect was caused by something other • than the suggested cause.

  21. William of Ockham, • Ockham, William of (1285-1349 )English philosopher who defended the logic, physics, and metaphysics of Aristotle in Summa Logicae (The Whole of Logic ) (1328) vol. 1 { at Amazon.com } and vol. 2 { at Amazon.com } and the Dialogus . An extreme nominalist , Ockham held that general terms are signs that indefinitely signify discrete (though similar) particulars. Ockham is best known for his statement of the law of parsimony as the ontological principle often called Ockham's Razor : " Frustra fit per plura quod potest fieri per pauciora " ["It is pointless to do with more what can be done with less"]. Thus, according to Ockham, we ought never to postulate the reality of any entity unless it is logically necessary to do so.

  22. William of Ockham Ockham’s Razor: “What can be accounted for by fewer assumptions in explained in vain by more.” His philosophy of science: “Nothing is assumed as evident unless it is known per se or is evident by experience, or is proved by authority of scripture.”

  23. Paracelsus (Phillippus Aureolus Theophrastus Bombastus von Hohenheim) ( 1493-1541 ) • Swiss chemist and physician. Rejecting the ancient reliance on concern for bodily "humours," Paracelsus transformed the practice of medicine by employing careful observation and experimentation. Although his chemical knowledge was rudimentary by modern standards, Paracelsus envisioned using pharmaceutical methods for treating disease and something like inoculation for preventing it.

  24. Scientific Development From 1543 to 1789 • 1543: Nicolas Copernicus (1473-1543) publishes De Revolutionibus Orbium Coelestium, which argues that the Sun is the center of the Solar System. • 1543: Andrea Vesalius (1514-1564) publishes Concerning the Structure of the Human Body, the first modern anatomical text. • 1600: William Gilbert (1540-1603) publishes Concerning the Magnet. • 1605: Francis Bacon (1561-1626) publishes Advancement of Learning. • 1609: Astronomia Novais published by Johannes Kepler (1571-1630), in which he presented his first two Laws of Planetary Motion. • 1610: Galileo Galilei (1564-1642) publishes Sidereal Messenger, describing his observations using the telescope. • 1619: Kepler publishes his Third Law inHarmonia Mundi.

  25. Scientific Development From 1543 to 1789 *1628: William Harvey (1578-1657) publishes On the Motion of the Heart and Blood in Animals, in which he proves that the heart circulates blood throughout the body. *1632: Galileo publishes Concerning the Two Chief World Systems, in which he compares the Copernican and Ptolemaic solar systems. *1637: Rene Descartes publishes his Discourse on Method, in which he lays the foundation for modern philosophy. *1644-9: Pierre Gassendi (1592-1655), in a series of works, revives the traditions of Epicureanism and Skepticism. *1660: Robert Boyle (1627-1691) publishes New Experiments Physico-Mechanical Touching the Spring of the Air, in which he states his laws of gases. *1662: The Royal Society of London is founded. `

  26. Scientific Development From 1543 to 1789 *1666: The French Academy of Science is founded. *1677: Anton von Leeuwenhoek (1632-1723), using a microscope, discovers male spermatoza. *1678: Christian Huygens (1629-1695) proposes the wave theory of light. *1687: Isaac Newton (1642-1727) publishes his Principia Mathematica. *1704: Isaac Newton publishes his Optics. *1735: Carolus Linnaeus publishes his Systema Naturae, which establishes the science of taxonomy. *1789: Antoine Lavoisier publishes his treatise on chemistry, laying the foundation for the modern theory of chemical elements.

  27. Copernicus b. 1473 Poland • Polish astronomer who developed the theory that the earth is a moving planet. In Copernicus's time, most astronomers accepted the theory the Greek astronomer Ptolemy had formulated nearly 1,400 years earlier. • Some astronomers before Ptolemy had suggested that the earth did in fact move. Copernicus decided that the simplest and most systematic explanation of heavenly motion required that every planet, including the earth, revolve around the sun. The earth also had to spin around its axis once every day. The earth's motion affects what people see in the heavens, so real motions must be separated from apparent ones. • Copernicus skillfully applied this idea in his masterpiece, On the Revolutions of the Heavenly Spheres (1543). In this book, he demonstrated how the earth's motion could be used to explain the movements of other heavenly bodies. Copernicus could not prove his theory, but his explanation of heavenly motion was mathematically strong and was less complicated than Ptolemy's theory. By the early 1600's, such astronomers as Galileo in Italy and Johannes Kepler in Germany began to develop the physics that would prove Copernicus' theory correct.

  28. Tycho Brahe b. 1546 • Danish astronomer. Brahe developed a systematic approach for observing the planets and stars. He stressed the importance of making such observations on a regular basis. The telescope had not yet been invented, and so Brahe used his eyesight and such instruments as astrolabes and quadrants to estimate the positions of celestial objects. His observations were far more precise than those of any earlier astronomer. • Brahe's observations of planetary motion revealed that the tables then in use to predict the positions of the planets were inaccurate. His sighting of a supernova (type of exploding star) in 1572 helped disprove the ancient idea that no change could occur in the heavens beyond the orbit of the moon. • Like many astronomers of his time, Brahe refused to accept the Copernican theory of the solar system. According to this theory, the earth and the other planets move around the sun. Brahe reasoned that if the earth revolved around the sun, he should have been able to measure changes in the positions of the stars resulting from the earth's movement. He did not realize that such changes were too small for his instruments to detect. However, Brahe's observational data later enabled Johannes Kepler, a German astronomer and mathematician, to confirm the Copernican theory. • Brahe was born in Knudstrup (then a Danish city but now in Sweden), near Malmo. As a member of the nobility, he attended universities in Denmark, Germany, and Switzerland. Brahe built an elaborate observatory on the island of Hven (now called Ven), where he made many of his observations.

  29. Tycho Brahe b. 1546 • Danish astronomer. Brahe developed a systematic approach for observing the planets and stars. He stressed the importance of making such observations on a regular basis. The telescope had not yet been invented, and so Brahe used his eyesight and such instruments as astrolabes and quadrants to estimate the positions of celestial objects. His observations were far more precise than those of any earlier astronomer. • Brahe's observations of planetary motion revealed that the tables then in use to predict the positions of the planets were inaccurate. His sighting of a supernova (type of exploding star) in 1572 helped disprove the ancient idea that no change could occur in the heavens beyond the orbit of the moon.

  30. Tycho Brahe (1546-1601)

  31. Johannes Kepler b. 1571 • Discovered three laws of planetary motion. • Newton later used Kepler's three laws to arrive at the principle of universal gravitation • Kepler's laws are: (1) Every planet follows an oval-shaped path, or orbit, around the sun, called an ellipse. The sun is located at one focus of the elliptical orbit. (2) An imaginary line from the center of the sun to the center of a planet sweeps out the same area in a given time. This means that planets move faster when they are closer to the sun. (3) The time taken by a planet to make one complete trip around the sun is its period. The squares of the periods of two planets are proportional to the cubes of their mean distances from the sun. • Kepler formed an association with Tycho Brahe, which shaped the rest of his life. His most significant discoveries trying to find an orbit to fit all Brahe's observations of the planet Mars. Earlier astronomers thought a planet's orbit was a circle or a combination of circles. However, Kepler could not find a circular arrangement to agree with Brahe's observations. He realized that the orbit could not be circular and resorted to an ellipse in his calculations. The ellipse worked, and Kepler destroyed a belief that was more than 2,000 years old. • Kepler was the first astronomer to openly uphold the theories of the Polish astronomer Nicolaus Copernicus.

  32. Johannes Kepler b. 1571 • Kepler formed an association with Tycho Brahe, which shaped the rest of his life. His most significant discoveries trying to find an orbit to fit all Brahe's observations of the planet Mars. Earlier astronomers thought a planet's orbit was a circle or a combination of circles. However, Kepler could not find a circular arrangement to agree with Brahe's observations. He realized that the orbit could not be circular and resorted to an ellipse in his calculations. The ellipse worked, and Kepler destroyed a belief that was more than 2,000 years old. • Kepler was the first astronomer to openly uphold the theories of the Polish astronomer Nicolaus Copernicus.

  33. Johannes Kepler b. 1571 FIRST LAW • The orbits of the planets are ellipses, with the Sun at one focus of the ellipse.

  34. Johannes Kepler b. 1571 SECOND LAW • The line joining the planet to the Sun sweeps out equal areas in equal times as the planet travels around the el

  35. Johannes Kepler b. 1571 THIRD LAW • The ratio of the squares of the revolutionary periods for two planets is equal to the ratio of the cubes of their semi-major axes: • T^2/R^3 = constant for all planets

  36. Gilbert, William (1540-1603), • Gilbert, William (1540-1603), an English doctor and scientist, was the first person to use the word electricity. He has been called the "Galileo of Magnetism" because of his celebrated book De Magnete, which he published in 1600. It was concerned with the properties of magnetism, with electricity, and with the use of compasses in navigation. • Gilbert's most important discoveries in the field of magnetism were the laws of attraction and repulsion, magnetic dip, and the properties of loadstones. Gilbert based his findings on observation and practical experiments. This practice differed greatly from that of most of the scientists of his time, who developed only abstract theories, unsupported by experiments. • Gilbert was born in Colchester, in Essex, England, and was educated at St. John's College, Cambridge. He was physician to Queen Elizabeth I and attended her during her last illness. Gilbert died on Nov. 30, 1603.

  37. William Harvey (1578-1657) • An English physician who became famous for his discovery of how blood circulates in mammals, including human beings. He described his discovery in An Anatomical Study of the Motion of the Heart and of the Blood in Animals (1628). This work became the basis for all modern research on the heart and blood vessels.

  38. Galileo Galilei

  39. Pendulum The Italian physicist Galileo discovered the laws of the pendulum. He noticed that a hanging lamp would swing with an almost constant period, whether the arc was large or small. He believed that a pendulum could regulate the movements of clocks. The Dutch scientist Christiaan Huygens patented the first pendulum clock in 1657. Galileo's observations are still correct as long as the pendulum's swing is small. But modern measuring instruments have shown that the period of a pendulum increases when it has a large swing.

  40. Pendulum • The Simple Pendulum • If a pendulum of mass m attached to a string of length L is displaced by an angle from the vertical, it experiences a net restoring force due to gravity: • In this small angle approximation, the amplitude of the pendulum has no effect on the period. This is what makes pendulums such good time keepers. As they inevitably lose energy due to frictional forces, their amplitude decreases, but the period remains constant.

  41. Astronomy and Kinematics • Galileo also pursued research on motion-especially the motion of freely falling bodies. The problem, as he saw it, was that the Aristotelian theory of motion, which referred all motion to a stationary earth at the center of the universe, made it impossible to believe the earth actually moves. Galileo went to work to develop a theory of motion consistent with a moving earth.

  42. Astronomy and Kinematics • In 1610 Galileo made observations of sunspots and of Venus, noting that the planet progresses through phases similar to those of the moon. This fact confirmed his doubts about Ptolemaic astronomy and deepened his conviction of the truth of Copernicus' theory that the earth and planets revolve around the sun. Publication of these findings, starting in 1610, brought him wide renown.

  43. Astronomy and Kinematics • Among the most important results of this search were the law of the pendulum and the law of freely falling bodies. Galileo observed that pendulums of equal length swing at the same rate whether their arcs are large or small. Modern measuring instruments show that the rate is actually somewhat greater if the arc is large. Galileo's law of falling bodies states that all objects fall at the same speed, regardless of their mass; and that, as they fall, the speed of their descent increases uniformly.

  44. GALILEO GALILEI1610 Published “The Starry Messenger”‘The Bible was written to show us how to go to heaven, not how the heavens go”“In discussions of physical problems we ought to begin not from the authority of scriptural passages, but from the sense-experiences and necessary demonstrations.”“For the Holy Bible and the phenomena of nature proceed alike from the divine Word, the former as the dictate of the Holy Spirit and the latter as the observant executor of God’s commands.”