HOME - Janux - D2L - Email Wikipedia course web page Vimeo course videos Course materials at iTunes U (optional) Twitter: #ouhoscurator
History of Science Notre Dame cathedral, Paris - 14th century

History of Science Online

- Course Info - Time tips - Semester at a glance - Weekly assignments at a glance - Timeline -

LibraryThing: Science in Ancient Mesopotamia Week 8: 14th-century Science

Readings 1: Background

# Due Date Pts Activity Time
2 Wednesday
11:59 p.m.

Topic 1 + Quiz
Background: Without a sense of context, history is anachronistic.
Primary sources: Without documentary evidence, history is speculation
The first of two topic assignments per week involving both background and primary sources.

90 min.

Here are the source reading assignments for this week. They provide just a few glimpses to sample the complex and innovative developments of 14th-century natural philosophy.

  1. Condemnations of 1277

  2. William Ockham on Divine Omnipotence and the Plurality of Worlds

  3. Theodoric of Freiberg and the Optics of the Rainbow

  4. Background readings this week are from David Lindberg, Beginnings of Western Science. Cf. Dates to remember. This week our focus will be on Lindberg's two chapters concerning the physical sciences. (Next week, as we move into the 15th century, we'll read Lindberg's Chapter 13 concerning life sciences.)
    1. 2nd ed., 2007:
    1. 1st ed., 1992:

From the Vault video text:

Thanks for joining me in the History of Science Collections of the University of Oklahoma Libraries. Let’s look at a couple treasures from the vault that throw light on the story of science in the 14th century.

This book contains lectures by John Duns Scotus, delivered in Oxford in 1302, printed much later in 1481. The rear wooden board bears a brand, burned into the surface, to identify it as belonging to the library of the Franciscans of Villengen, near Strassburg. It contains extensive annotations. Scotus, along with other 14th century theologians and philosophers such as William Ockham, Jean Buridan, and Nicole Oresme, mounted a critique of Thomas Aquinas’ synthesis of science and faith, arguing that divine omnipotence required the created order to be contingent, and therefore not completely transparent to rational demonstration. Pierre Duhem and many more recent scholars have shown that, if nature is contingent, that is, if it might have been made otherwise than it is, then Aristotle’s logic, physics and cosmology would all have to be revised to allow more than one possible outcome. In the hands of these 14th-century writers, a critique of rational necessity led to such ideas as the possible existence of other worlds, a rotating Earth, and an Earth characterized not by eternity but by a very ancient history that might be reconstructed on the basis of empirical evidence.

One expression of this 14th-century critique of rational necessity was an increasing role for experiment. If nature is contingent, then experimental methodologies will be essential to grasp the natural order. One example of a 14th-century experimental tradition is the investigation into the optics of the rainbow by the monk Theodoric of Freiberg. Theodoric experimented with spherical flasks, filled with water, to model individual raindrops in a cloud, with the sunlight shining on them from a crack in the ceiling. He observed that different colors appeared as he would raise the flask higher or lower. By covering certain portions of the flask at a time, one after another, to see where the light would come out, Theodoric determined the path that light follows from the Sun through the drop to the human eye to create a rainbow. Theodoric's explanation of the primary and secondary rainbows as a result of refraction and reflection is still regarded as correct; that is, the paths traced by the rays of light through raindrops to produce both the primary and secondary rainbows was confirmed by Descartes in the 17th century, as printed in this work. For this reason, Theodoric of Freiberg's discovery of the optics of the rainbow is often regarded as a triumph of experimental methodology in the late middle ages.

Science is a story. What stories do you want to hear and tell about 14th-century science?

TOPIC QUIZ: The statements are either True or False. When you take the quiz at Janux, you will see 12 of these statements, chosen at random, worth 2 points each.

  1. T or F? According to the Averroist interpretation of Aristotle, the natural order is determined and necessary.
  2. T or F? According to the Averroist interpretation of Aristotle, the universe is contingent.
  3. T or F? The Condemnation of 1277 prohibited university professors across Europe from teaching 219 propositions.
  4. T or F? Duhem regarded the Condemnation of 1277 as the death-knell of medieval science.
  5. T or F? After the Condemnation of 1277, medieval scientists accepted the authority of Aristotle in all matters of natural science.
  6. T or F? Many medieval scientists used the doctrine of divine omnipotence to argue for the contingency of nature. T or F? In 1277, Bishop Tempier condemned the thesis that there might be a plurality of worlds. T or F? Oresme argued that proofs that the Earth lies in the center of the universe are inconclusive. T or F? Oresme argued that proofs that the Earth is motionless, and does not rotate on its axis, are inconclusive. T or F? Oresme used a principle of relative motion to refute arguments based on sense experience. T or F? Oresme used a principle of phenomenalism, that ordinary language is accommodated to the appearances of things, to refute arguments based on reason and biblical interpretation. T or F? Oresme relied on a principle of parsimony to argue for the rotation of the Earth. T or F? Oresme argued that we cannot determine whether the sphere of fixed stars spins around us once a day or whether the Earth turns on its axis once a day, because the same observations would result either way. T or F? The Theory of the Earth of Buridan and Oresme distinguished between the center of gravity of the sphere of water and the center of volume or magnitude of earth. T or F? The Theory of the Earth of Buridan and Oresme assumed that the far side of the Earth is a watery hemisphere. T or F? The Theory of the Earth of Buridan and Oresme assumed that the Earth was created only a few thousand years ago. T or F? The Theory of the Earth of Buridan and Oresme offered an explanation for why the crust of the dry land is made of rock layers. T or F? The Theory of the Earth of Buridan and Oresme offered an explanation for earthquakes. T or F? The Theory of the Earth of Buridan and Oresme offered an explanation for the existence of marine fossils on the tops of mountains. T or F? The Theory of the Earth of Buridan and Oresme offered an explanation for the changing locations of stars, over vast amounts of time, as they rise and set on the horizon. T or F? According to Oresme's Mean Speed Theorem, a body moving with uniformly accelerated motion covers the same distance in a given time as if it were to move for the same duration with a uniform speed equal to its mean (or average) speed. T or F? Distances traveled by a body moving with uniform acceleration increase as the square of the times. T or F? Oresme expressed the Mean Speed rule graphically, in a manner very similar to Galileo. T or F? For Ockham, all that is not divine is utterly contingent and could have been otherwise. T or F? Ockham's razor was a principle of economy that undermined conclusions reached by reasoning from universals. T or F? For Ockham, universals are necessary truths. T or F? Ockham rejected Aristotle's theory of absolute natural place, and substituted a theory of relative natural place. T or F? Theodoric of Freiberg experimented with a spherical flask filled with water to model the optics of a single raindrop. T or F? Theodoric of Freiberg explained the optics of the primary rainbow. T or F? Theodoric of Freiberg explained the optics of the secondary rainbow. T or F? Refraction occurs when light is bounced off the far side of a drop of water, remaining within the drop. T or F? In the 17th century, Descartes confirmed Theodoric's explanation of the paths traced by rays of light within drops of water. T or F? Theodoric of Freiberg, a medieval natural philosopher with a university education and a member of a monastic order, rejected the experimental method. T or F? In an outbreak of the Black Plague that started in 1348, 30-50% of the European population died. T or F? In the Decameron, Boccaccio described the outbreak of the plague in Paris. T or F? According to Boccaccio, most people died within about three days of the appearance of tumors. T or F? According to Boccaccio, despite the quantity of dead bodies, churches resolutely maintained the ancient custom of burying the dead in individual graves grouped by family. T or F? Though the plague ravaged some universities on the European continent, Cambridge University in England was largely unaffected.
  7. T or F ? According to medieval cosmology, the Earth was believed to be flat.
  8. T or F? In what one might call a medieval version of the Big Bang theory, Robert Grosseteste envisioned the universe beginning as a point of light that evolved into a spherical universe containing the stars and planets.
  9. T or F? After the condemnations of 1277, physicists were required to affirm that multiple worlds might exist.
  10. T or F? After the condemnations of 1277, physicists were required to affirm that space, even if empty, might exist outside the universe.
  11. T or F? Medieval cosmologists were agreed that Aristotle’s unmoved movers of the celestial spheres must be angels.
  12. T or F? Jean Buridan attributed the motions of the celestial spheres to impetus, and thus had no need for unmoved movers.
  13. T or F? In Aristotelian cosmology, four elements comprise the region below the sphere of the Sun.
  14. T or F? In Aristotelian cosmology, comets were believed to occur above the Moon.
  15. T or F? Theodoric of Freiberg explained the optics of the rainbow on the basis of refraction and reflection within individual raindrops.
  16. T or F? Nicole Oresme thought he could prove that the Earth lies motionless in the center of the universe.
  17. T or F? The sight (or sighting rule) of an astrolabe is called a rete.
  18. T or F? Each lower plate, or climate, of an astrolabe is specific to a particular latitude, and needs to be changed out in order to use the astrolabe when one travels to a location much farther north or south.
  19. T or F? Islamic astronomers such as Ibn al Haytham, Ibn Bajja, al-Bittruji, and others, tended to adopt an instrumentalist view of astronomical models.
  20. T or F? Sacrobosco’s Sphere (De Sphaera) served as a standard medieval introduction to spherical astronomy, explaining such topics as the Sun’s motion along the ecliptic and how epicycle models in principle can explain retrograde motions of the planets.
  21. T or F? The Theorica planetarum served as a standard medieval introduction to planetary astronomy, explaining specific models for each of the planets using deferents, eccentrics, and epicycles.
  22. T or F? Astrology defined as a set of beliefs about physical influences coming down upon us from the cosmos was much contested in the Middle Ages.
  23. T or F? Ptolemy’s treatise on astrology is called the Almagest.
  24. T or F? The Church sought to establish limits on the degree to which deterministic astrological influences might affect human life.
  25. T or F? In the 14th century, astrology had become an established part of university medicine.
  26. T or F? According to Aristotle, all forms are composed of substances and matter.
  27. T or F? Medieval physicists discussed the nature of minima naturalis, conceived as the smallest pieces of the ingredients of a mixture that, if divided, would still retain the properties of the mixture.
  28. T or F? Minima and atoms were basically the same thing.
  29. T or F? According to medieval physics, if one could alter the quality of an element (its coldness, wetness, hotness or dryness), then one could transform that element into a different element.
  30. T or F? Medieval achemists developed laboratory techniques such as distillation and fermentation.
  31. T or F? 14th century scholars at Merton College, Oxford, conceived and worked out the implications of the idea of instantaneous velocity.
  32. T or F? Kinematics refers to the study of the causes of motion; dynamics to the description of motion.
  33. T or F? According to the Merton scholars, uniform acceleration is the same as uniform velocity.
  34. T or F? In Oresme’s graphs of velocity and time (eg Fig 12.7b), the distance traversed by a moving body equals the area of the figure.
  35. T or F? The Mean Speed Theorem, or Merton rule, claims that a body moving with uniform acceleration (AEG in Fig 12.8) covers the same distance as a second body moving with uniform velocity (FED in Fig 12.8) when the speed of the second body is the mean (BE) of the initial (A) and final (CG) speeds of the first body.
  36. T or F? In Fig 12.8, a body accelerating with speeds from A to G covers the same distance as the body moving with constant speed F to D.
  37. T or F? Buridan used impetus theory to explain the motion of the spheres, falling bodies, and projectile motion.
  38. T or F? According to Aristotle, the heavier an object, the faster it falls.
  39. T or F? According to Aristotle, a vacuum cannot exist because a body would move through a vacuum with infinite speed.
  40. T or F? Thomas Bradwardine challenged Aristotle’s theory of motion by noting that a common mathematical formulation of it could not predict zero velocity in cases of high resistance.
  41. T or F? Aristotle and the ancient atomists developed extramission theories of vision.
  42. T or F? Ibn al-Haytham (Alhazen) argued that only one ray from each point in the visual field falls on the eye perpendicularly; all others are weakened by refraction and play no role in vision.
  43. T or F? Roger Bacon, John Pecham, and Witelo rejected Ibn al-Haytham’s optical theories.


"It is true that the medieval Schoolmen, who had produced the finest logic that the world has ever seen, had in later years produced more logic than the world can ever be expected to stand." G.K. Chesterton

University of Oklahoma logo

HSCI 3013. History of Science to 17th centuryCreative Commons license
Kerry Magruder, Instructor, 2004
Brent Purkaple, TA

Report typos or broken links

Go to this course at

spellcheck.net | wordcounter.net

Many thanks to the pedagogical model developed in Mythology and Folklore and other online courses by Laura Gibbs, which have been an inspiration for this course.

Academic Calendar

College of Arts and Sciences Online



This course is currently undergoing major reconstruction to bring it into alignment with the new version of the course at Janux