Medieval Science: An Overview

picture of a gold astrolabe"Wherefore, dearest son, whom God has made wholly happy in this regard, in so far as those things are offered freely, for which many at the greatest peril of life plough the sea waves compelled to endure hunger and cold, or which others, wearied with long servitude in the schools and not exhausted by the desire of learning, only acquire with intolerable labour-be eager and anxious to look at this little work on the various arts, read it through with a retentive memory, and cherish it with a warm affection. If you will diligently examine it, you will find in it whatever kinds and blends of various colours Greece possesses: whatever Russia knows of workmanship in enamels or variety of niello: whatever Arabia adorns with repoussé or cast work, or engravings in relief: whatever gold embellishments Italy applies to various vessels or to the carving of gems and ivories: whatever France esteems in her precious variety of windows: whatever skilled Germany praises in subtle work in gold, silver, copper, iron, wood, and stone."
--Theophilus, An Essay Upon Diverse Arts, c. 1125 (early Medieval text in Metallurgy)

Formative Elements

painting of a codex by Alfonso Caso
  1. Belief in an orderly creation designed by God provides the necessary framework for science as a discipline to arise. Such a belief offers a picture of the world as regular, predictable, and uniform. Likewise, the world is considered knowable by human beings and worthy of investigation.

  2. The stress on applying reason to natural problems, as opposed to an unthinking acceptance of tradition, also prepared the way for science to develop.

  3. As strange as it may sound, medieval alchemy helped prepare the way for some aspects of scientific reasoning. The alchemists' stress on formal methodology, their work with chemicals, and the process of elimination of possibilities paved the way for more exacting procedures.

  4. Greco-Arabic science translations into Latin (Adelard of Bath, Gerard of Cremona), including Euclid's Elements, Aristotle's Physics, Ptolemy's Almagest, created a strong interest in natural descriptions of the universe and eventually gave rise to observations that would disconfirm the assertions of Aristotle and Ptolemy in regard to physics and cosmology.

  5. Medieval university (stadium generale) curriculum included geometry, arithmetic, music, astronomy, natural philosophy and eventually medicine.

  6. Natural philosophy became an important element in the work of theologians, such as Albertus Magnus, John Pecham, and Theodoric of Freiberg.

Key Scientific Concepts

  1. Precise measurement of time (Bede of Northumbria) was a necessary precursor of scientific study.

  2. The adopting of Arabic numbers by the 13th century made modern mathematical study possible.

  3. Mathematical treatment of problems (Thomas Bradwardine), including astronomy, was associated especially with the work of the Merton College "calculators" of the 1330-1340's and spread to the University of Paris.

  4. A stress on mathematics as key tool for explaining the natural world, as well as a stress on observation, hypothesis, and verification (Robert Grosseteste, Roger Bacon) foreshadowed Renaissance and Early Modern procedures.

  5. Ockham's Razor states that "entities should not be multiplied beyond necessity" (entia non sunt multiplicanda praeter necessitatem), meaning that procedural simplicity should be preferred in a hypothesis. Unnecessary assumptions only compound a theory with the potential for error. The idea is that theories should be as simple as the evidence allows; this doesn't preclude the introduction of complexity in a theory when called for.

  6. Scholastic views on contingency, necessity, and causality were important precursors, as well.

  7. Some, though by no means a majority, rejected final causes in natural philosophy and accepted degrees of certitude as necessary in scientific exploration (John Buridan).

  8. The philosophical debate surrounding the annihilation of matter and the concept of an infinite void of space prepared the way for seventeenth-century theories of Newton and others.

  9. Aristotelian terminology provided a large vocabulary for future scientific thinking: "potential, actual, substance, property, accident, cause, analogy, matter, form, essence, genus, species, relation, quantity, quality, place, vacuum, and infinite" (Grant 198).

  10. Likewise the medieval treatment of "counterfactuals," "natural impossibilities," or "thought experiments" allowed for speculations that would call into question Aristotelian physics (Grant 196).

Scientific Discoveries

  • Medical advances

  • Technological advances, including percussion drilling, glass mirrors, windmills, compasses, wheelbarrows, and blast furnaces.

  • Post-mortem dissections

  • Advances in optics, theories of light and color

  • Advances in harmonics and musicology

  • Advances in metallurgy

  • Causes and effects of motion [dynamics and kinematics] (14thc. Paris and Oxford)

  • Latitudo qualitatis (intensio) versus longitudo qualitatis (extensio) [intensity of a quality vs. quantity of a quality distributed] (Nicolas Oresme)


"Questions on Nature" from Adelard of Bath (MR 620-626)

  1. Why does Adelard begin this selection decrying English vices?

  2. What do you find intriguing or surprising about the list of causes Adelard includes?

  3. How does he contrast authority and reason?

  4. What are some of his claims about the nature of bodies?

Ancient Theory of the Bodily Humours

Temper: Melancholic

Organ: Spleen

Nature: Cold Dry

Element: Earth

Temper: Phlegmatic

Organ: Lungs

Nature: Cold Wet

Element: Water

Temper: Sanguine

Organ: Head

Nature: Warm Wet

Element: Air

Temper: Choleric

Organ: Gall Bladder

Nature: Warm Dry

Element: Fire

"Experimental Science" from Roger Bacon (MR 626-635)

  1. How does Bacon distinguish reasoning and experience? Why does he prefer the later?

  2. Why does even mathematics need experiential proof?

  3. Why does he distinguish experimentation and revelation?

  4. What surprises you about the examples he provides?

painting of a medieval sickroom"The Case of a Woman Doctor in Paris" & "The History of Surgery" 
(MR 635-650)

  1. What is the gist of the medical faculty's charge against Jacoba?

  2. What procedures does she use to heal patients?

  3. What is the legal reasoning used to vindicate Jacoba?

  4. What does Guy's list of surgical authorities reveal?

  5. What five sects of medical practice does Guy seek to refute? How does he do so?

  6. What qualifications does he recommend that the surgeon have?

  7. What qualities are necessary for the patient and the attendants?

Grant, Edward. The Foundations of Modern Science in the Middle Ages. Cambridge: Cambridge UP, 1996.

medieval anatomical painting