History of science in the Middle Ages

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The history of science in the Middle Ages is concerned with the study of nature, including practical disciplines, the mathematical sciences, and natural philosophy, throughout the Middle Ages - the middle period in a traditional schematic division of European history. Although the term 'Middle Ages' usually refers to European history, scientific advances in the Eastern world will also be accounted for in the present article.

Western Europe entered the Middle Ages with great difficulties that affected the continent's intellectual production dramatically. Most classical scientific treatises of classical antiquity (in Greek) were unavailable, leaving only compilations and summaries that were often corrupted in the process of copying and translating. Notwithstanding, with the beginning of the Renaissance of the 12th century, interest in natural investigation was renewed. Science developed in this golden period of Scholastic philosophy focused on logic and advocated empiricism, perceiving nature as a coherent system of laws that could be explained in the light of reason.

With this view the medieval men of science went in search of explanations for the phenomena of the universe and achieved important advances in areas such as scientific methodology and physics, among many others. These advances, however, were suddenly interrupted by the Black Plague and are virtually unknown to the lay public of today, partly because most theories advanced in medieval science are today obsolete, and partly because of the stereotype of Middle Ages as supposedly "Dark Ages".

Contents

The Middle Ages: Western World

Early Middle Ages

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In the Early Middle Ages, cultural life was concentrated at monasteries.

See also: Medieval medicine, Medieval philosophy

The Western Roman Empire, although united by the latin language, still harbored a great number of different cultures that were not completely assimiliated by the Roman culture. Debilitated by migrations, barbarian invasions and the political disintegration of Rome in the 5th century, and isolated from the rest of the world by the spread of Islam in the 7th century, the European West became a tapestry of rural populations and semi-nomad peoples. The political instability and the downfall of urban life had a strong, negative impact on the cultural life of the continent. The Catholic Church, being the only institution to survive the process, maintained what was left of intellectual strength, especially through monasticism.

The intellectual of these early centuries was almost always a clergyman for whom the study of nature was but a small part of instruction. These intellectuals lived in an atmosphere which provided little institutional support for the disinterested study of natural phenomena. The study of nature was pursued more for practical reasons (e.g., medicine, astronomical timekeeping) than as an abstract inquiry. A further disconcerting aspect of the science of this period for modern readers is that the same people and the same works would sometimes discuss both the symbolic significance of natural phenomena and their technical details. Most scientific inquiry was based on information gleaned from sources from antiquity, sources which were often incomplete and posed serious problems of interpretation. Given the limited scientific advances from about 476 to about 1000, this period came to be known in popular culture as the Dark Ages. Nowadays, most modern historians dismiss the use of the term by pointing out that the labelling of this era as "dark" was mostly based on previous ignorance about the period combined with popular stereotypes.

In the end of the 8th century the first attempt at rebuilding Western culture occurred. Charles the Great, having succeeded at uniting a great portion of Europe under his domain, and in order to further unify and strengthen his empire, decided to carry out a reform in education. The English monk Alcuin of York elaborated a project of scholarly development aimed at resuscitating classical knowledge by establishing programs of study based upon the seven liberal arts: the trivium, or literary education (grammar, rhetoric and dialectic) and the quadrivium, or scientific education (arithmetic, geometry, astronomy and music). From the year 787 on, decrees began to circulate recommending, in the whole empire, the restoration of old schools and the founding of new ones. Institutionally, these new schools were either under the responsibility of a monastery, a cathedral or a noble court.

The significance of these measures would only be felt centuries later. The teaching of dialectic (a discipline that corresponds to today's logic) was responsible for the rebirth of the interest in speculative inquiry; from this interest would follow the rise of the Scholastic tradition of Christian philosophy. Moreover, in the 12th and 13th century, many of those schools founded under the auspices of Charles the Great, especially cathedral schools, would become universities.

High Middle Ages

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See Also: Renaissance of the 12th century, Medieval technology

The cultural scenario starts to change in the 12th century, when the contact with the Arabs after the Reconquista and during the Crusades, (mainly in Sicily and Spain), allowed Europeans access to preserved copies of Greek and Roman works. This period also saw the birth of medieval universities, these universities aided materially in the translation, preservation and propagation of the texts of the ancients and started a new infrastructure which was needed for scientific communities.

The rediscovery of the works of Aristotle through medieval Jewish and Muslim Philosophy (Maimonides, Avicenna, and Averroes) allowed the development of the new Christian philosophy and method of scholasticism. By 1200 there were reasonably accurate Latin translations of the main works of Aristotle, Plato, Euclid, Ptolemy, Archimedes and Galen, that is, of all the intellectually crucial ancient authors except Thucydides. During the thirteenth century the natural philosophy of these texts began to be extended by notable Scholastics such as Robert Grosseteste, Roger Bacon, Albertus Magnus, and Duns Scotus.

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God creating the universe after geometric and harmonic principles. To seek these principles was therefore to seek and worship God.

Scholastics believed in empiricism and supporting Roman Catholic doctrines through secular study, reason, and logic. The most famous was Thomas Aquinas (later declared a "Doctor of the Church"), who led the move away from the Platonic and Augustinian and towards Aristotelianism, but natural philosophy wasn't his main concern. Meanwhile, precursors of the modern scientific method can be seen already on Grosseteste's emphasis on mathematics as a way to understand nature and on the empirical approach admired by Roger Bacon.

Grosseteste was the founder of the famous Oxford franciscan school. He was the first scholastic to fully understand Aristotle's vision of the dual path of scientific reasoning. Concluding from particular observations into a universal law, and then back again: from universal laws to prediction of particulars. Grosseteste called this "resolution and composition". Further, Grosseteste said that both paths should be verified through experimentation in order to verify the principals. These ideas established a tradition that carried forward to Padua and Galileo Galilei in the 17th century.

Under the tuition of Grosseteste and inspired by the writings of Arab alchemists who had preserved and built upon Aristotle's portrait of induction. Bacon described a repeating cycle of observation, hypothesis, experimentation, and the need for independent verification. He recorded the manner in which he conducted his experiments in precise detail so that others could reproduce and independently test his results - a cornerstone of the scientific method, and a continuation of the work of researchers like Al Battani.

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Optic studies from Robert Grosseteste's De Natura Locorum. The diagram shows light being refracted by a spherical glass container full of water.
Bacon and Grosseteste conducted investigations into optics, although much of it was similar to what was being done at the time by Arab scholars. Bacon did make a major contribution to the development of science in medieval Europe by writing to the Pope to encourage the study of natural science in university courses and compiling several volumes recording the state of scientific knowledge in many fields at the time. He described the possible construction of a telescope, but there is no strong evidence of his having made one.

Late Middle Ages

The first half of the 14th century saw the scientific work of great thinkers. The logic studies by William of Occam led him to postulate the principle known today as Occam's Razor. According to Occam, philosophy should only concern itself with subjects on which it could achieve real knowledge, a principle often referred to as parsimony. This should lead to a decline in fruitless debates and move philosophy toward experimental science.

By the time, some scholars, such as Jean Buridan, started to question the received wisdom of Aristotle's mechanics, he developed the theory of impetus which was the first step towards the modern concept of inertia. Buridan anticipated Isaac Newton when he wrote:

...after leaving the arm of the thrower, the projectile would be moved by an impetus given to it by the thrower and would continue to be moved as long as the impetus remained stronger than the resistance, and would be of infinite duration were it not diminished and corrupted by a contrary force resisting it or by something inclining it to a contrary motion

Thomas Bradwardine and his partners, the Oxford Calculators of Merton College, distinguished kinematics from dynamics, emphasizing kinematics, and investigating instantaneous velocity. They first formulated the mean speed theorem: a body moving with constant velocity travels distance and time equal to an accelerated body whose velocity is half the final speed of the accelerated body. They also demonstrated this theorem -- essence of "The Law of Falling Bodies" -- long before Galileo is credited with this.

In his turn, Nicole Oresme showed that the reasons proposed by the physics of Aristotle against the movement of the earth were not valid and adduced the argument of simplicity for the theory that the earth moves, and not the heavens. In the whole of his argument in favor of the earth's motion Oresme is both more explicit and much clearer than that given two centuries latter by Copernicus. He was also the first to assume that color and light are of the same nature and the discoverer of the curvature of light through atmospheric refraction; even though, up to now, the credit for this latter achievement has been given to Hooke.

However, a series of events that would be known as the Crisis of the Late Middle Ages was under its way. When came the Black Death of 1348, it sealed a sudden end to the previous period of massive scientific change. The plague killed a third of the people in Europe, especially in the crowded conditions of the towns, where the heart of innovations lay. Recurrences of the plague and other disasters caused a continuing decline of population for a century.

Renaissance of the 15th century

's , an example of the blend of art and science during the Renaissance
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Leonardo da Vinci's Vitruvian Man, an example of the blend of art and science during the Renaissance
See also: Renaissance

The 15th century saw the beginning of the cultural movement of the Renaissance.

The rediscovery of ancient texts was accelerated after the Fall of Constantinople, in 1453, when many Byzantine scholars had to seek refuge in the West, particularly Italy. Also, the invention of printing was to have great effect on European society: the facilitated dissemination of the printed word democratized learning and allowed a faster propagation of new ideas.

But this initial period is usually seen as one of scientific backwardness. There were no new developments in physics or astronomy, and the reverence for classical sources further enshrined the Aristotelian and Ptolemaic views of the universe. Humanism stressed that nature came to be viewed as an animate spiritual creation that was not governed by laws or mathematics. At the same time philosophy lost much of its rigour as the rules of logic and deduction were seen as secondary to intuition and emotion.

It would not be until the Renaissance moved to Northern Europe that science would be revived, with such figures as Copernicus, Francis Bacon, and Descartes (though Descartes is often described as an early Enlightenment thinker, rather than a late Renaissance one).


Great names of science in medieval Europe

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Robert Grosseteste (1168-1253), Bishop of Lincoln, was the central character of the English intellectual movement in the first half of the 13th century and is considered the founder of scientific thought in Oxford. He had a great interest in the natural world and wrote texts on the mathematical sciences of optics, astronomy and geometry. In his commentaries on Aristotle's scientific works, he affirmed that experiments should be used in order to verify a theory, testing its consequences. Roger Bacon was influenced by his work on optics and astronomy.<ref>A. C. Crombie, Robert Grosseteste and the Origins of Experimental Science 1100-1700, (Oxford: Clarendon Press, 1971)</ref>


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Albert the Great (1193-1280), Doctor Universalis, was one of the most prominent representatives of the philosophical tradition emerging from the Dominican Order. He is one of the thirty-three Saints of the Catholic Church honored with the title of Doctor of the Church. He became famous for his vast knowledge and for his defence of the pacific coexistence between science and religion. Albert was an essential figure in introducing Greek and Islamic science into the medieval universities, but not without hesitation with particular aristotelian theses. In one of his most famous sayings he asserted: "Science does not consist in ratifying what others say, but of searching for the causes of phenomena." Thomas Aquinas was his most famous pupil.


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Roger Bacon (1214-1294), Doutor Admirabilis, joined the Franciscan Order around 1240 where, influenced by Grosseteste, he dedicated himself to studies where he implemented the observation of nature and experimentation as the foundation of natural knowledge. Bacon was responsible for making the concept of "laws of nature" widespread, and contributed in such areas as mechanics, geography and, most of all, optics.

The optical research of Grosseteste and Bacon made possible the beginning of the fabrication of eyeglasses in the 12th century. The same research would also prove invaluable for the later invention of such instruments as the telescope and the microscope.


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Thomas Aquinas (1227-1274), Doctor Angelicus, was an Italian theologian and friar in the Dominican Order. As his mentor Albert the Great, he is a Catholic Saint and Doctor of the Church. His interests were not only in philosophy; he was also interested in alchemy, having written an important treatise titled Aurora Consurgens. However, his greatest contribution to the scientific development of the period was having been the greatest responsible for the definitive incorporation of aristotelism in the Scholastic tradition.


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Duns Scotus (1266-1308), Doctor Subtilis, was a member of the Franciscan Order, philosopher and theologian. Emerging from the academic environment of the University of Oxford. where the presence of Grosseteste and Bacon was still palpable, he had a different view on the relationship between reason and faith as that of Thomas Aquinas. For Duns Scotus, the truths of faith could not be comprehended through the use of reason. Philosophy, hence, should not be a servant to theology, but act independently. He was the mentor of one of the greatest names of philosophy in the Middle Ages: William of Ockham.


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William of Ockham (1285-1350), o Doctor Invincibilis, was an English Franciscan friar, philosopher, logician and theologian. Ockham defended the principle of parsimony, which could already be seen in the works of his mentor Duns Scotus. His principle later became known as Occam's Razor and states that if there are various equally valid explanations for a fact, then the simplest one should be chosen. This became a foundation of what would come to be known as the scientific method and one of the pilars of reductionism in science. Ockham probably died of the Black Plague. Jean Buridan and Nicolas Oresme were his followers.


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Jean Buridan (1300-1358) was a French philosopher and priest. Although he was one of the most famous and influent philosophers of the late Middle Ages, his work today is not renowned by people other than philosophers and historians. One of his most significant contributions to science was the development of the theory of Impetus, that explained the movement of projectiles and objects in free-fall. This theory gave way to the dynamics of Galileo Galilei and for Isaac Newton's famous principle of Inertia.


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Nicolas Oresme (c.1323-1382) was an intellectual genius and perhaps the most original thinker of the 14th century. A theologian and Bishop of Lisieux, he was one of the principal propagators of the modern sciences. Notwithstanding his strictly scientific contributions, Oresme strongly opposed astrology and speculated about the possibility of extraterrestrial life. He was the last great European intellectual to live before the Black Plague, an event that had a very negative impact in the intellectual life of the ending period of the Middle Ages.

The Middle Ages: Eastern World

Islamic science

Main article: Islamic science
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Sample of Islamic medical text

In the Middle East, Greek philosophy was able to find some short-lived support by the newly created Islamic Caliphate (Islamic Empire). With the spread of Islam in the 7th and 8th centuries, a period of Islamic scholarship lasted until the 15th century. In the Islamic World, the Middle Ages is known as the Islamic Golden Age, when Islamic civilization and Islamic scholarship flourished. This scholarship was aided by several factors. The use of a single language, Arabic, allowed communication without need of a translator. Translations of Greek texts from Egypt and the Byzantine Empire, and Sanskrit texts from India, provided Islamic scholars a knowledge base to build upon. In addition, there was the Hajj. This annual pilgrimage to Makkah facilitated scholarly collaboration by bringing together people and new ideas from all over the Islamic world.

In Islamic versions of early scientific method, ethics played an important role. During this period the concepts of citation and peer review were developed. Islamic scholars used previous work in medicine, astronomy and mathematics as bedrock to develop new fields like alchemy. In mathematics, the Islamic scholar Muhammad ibn Musa al-Khwarizmi gave his name to what we now call an algorithm, and the word algebra is derived from al-jabr, the beginning of the name of one of his publications in which he developed a system of solving quadratic equations. Researchers like Al-Batani (850-929) contributed to the fields of astronomy and mathematics and Al-Razi to chemistry. Examples of fruits of these contributions can be seen in Damascus steel (wootz steel), and the Baghdad Battery. Arab alchemy proved to be an inspiration to Roger Bacon, and later to Isaac Newton. Also in astronomy, Al-Batani improved the measurements of Hipparchus, preserved in the translation of the Greek Hè Megalè Syntaxis (the great treatise) translated as Almagest. About 900, Al-Batani improved the precision of the measurement of the precession of the earth's axis, thus continuing a millennium's legacy of measurements in his own land (Babylonia and Chaldea- the area now known as Iraq).

Indian science

Main article: Indian science and technology

Prior to the Middle Ages, Indian philosophers in ancient India developed atomic theories, which included formulating ideas about the atom in a systematic manner and propounding ideas about the atomic constitution of the material world. The principle of relativity was also available in an early embryonic form in the Indian philosophical concept of "sapekshavad". The literal translation of this Sanskrit word is "theory of relativity" (not to be confused with Einstein's theory of relativity).

By the beginning of the Middle Ages, the wootz, crucible and stainless steels were invented in India. The spinning wheel used for spinning thread or yarn from fibrous material such as wool or cotton was invented in the early Middle Ages. By the end of the middle ages, iron rockets were developed in the kingdom of Mysore in South India.

The mathematician and astronomer Aryabhata in 499 propounded a heliocentric solar system of gravitation where he presented astronomical and mathematical theories in which the Earth was taken to be spinning on its axis and the periods of the planets were given as elliptical orbits with respect to the sun. He also believed that the moon and planets shine by reflected sunlight and that the orbits of the planets are ellipses. He carried out accurate calculations of astronomical constants based on this system, such as the periods of the planets, the circumference of the earth, the solar eclipse and lunar eclipse, the time taken for a single rotation of the Earth on its axis, the length of earth's revolution around the sun, and the longitudes of planets. He also introduced a number of trigonometric functions (including sine, versine, cosine and inverse sine), trigonometric tables, and techniques and algorithms of algebra. Arabic translations of his texts were available in the Islamic world by the 8th-10th century.

In the 7th century, Brahmagupta briefly described the law of gravitation, and recognized gravity as a force of attraction. He also lucidly explained the use of zero as both a placeholder and a decimal digit, along with the Hindu-Arabic numerals now used universally thorughout the world. Arabic translations of his texts (around 770) introduced this number system to the Islamic world, where it was adapted as Arabic numerals. Islamic scholars carried knowledge of this number system to Europe by the 12th century and it has now displaced all older number systems throughout the world.

The Siddhanta Shiromani was a mathematical astronomy text written by Bhaskara in the 12th century. The 12 chapters of the first part cover topics such as: mean longitudes of the planets; true longitudes of the planets; the three problems of diurnal rotation; syzygies; lunar eclipses; solar eclipses; latitudes of the planets; risings and settings; the moon's crescent; conjunctions of the planets with each other; conjunctions of the planets with the fixed stars; and the patas of the sun and moon. The second part contains thirteen chapters on the sphere. It covers topics such as: praise of study of the sphere; nature of the sphere; cosmography and geography; planetary mean motion; eccentric epicyclic model of the planets; the armillary sphere; spherical trigonometry; ellipse calculations; first visibilities of the planets; calculating the lunar crescent; astronomical instruments; the seasons; and problems of astronomical calculations.

From the 12th century, Bhaskara, Madhava, and various Kerala School mathematicians first conceived of mathematical analysis, differential calculus, concepts of integral calculus, infinite series, power series, Taylor series, trigonometric series, floating point numbers, and many other concepts foundational to the overall development of calculus and analysis.

Chinese science

Main article: Science and technology in China

The solid-fuel rocket was invented in China about 1150, about 200 years after the invention of gunpowder (which was its main fuel) and 500 years after the invention of the match. At the same time that the age of exploration was occurring in the West, the Chinese emperors of the Ming Dynasty also sent ships, some reaching Africa. But the enterprises were not further funded, halting further exploration and development. When Magellan's ships reached Brunei in 1521, they found a wealthy city that had been fortified by Chinese engineers, protected by a breakwater. Antonio Pigafetta noted that much of the technology of Brunei was equal to Western technology of the time. Also, there were more cannons in Brunei than on Magellan's ships, and the Chinese merchants to the Brunei court had sold them spectacles and porcelain, which were rarities in Europe. The scientific base for these technological developments appears to be quite thin, however. For example, the concept of force was not clearly formulated in Chinese texts of the period.

Notes

<references/>

References

Grant, E. The Foundations of Modern Science in the Middle Ages: Their Religious, Institutional and Intellectual Contexts. Cambridge: Cambridge Univ. Pr., 1996. ISBN 0-521-56762-9

Grant, E., ed. A Sourcebook in Medieval Science. Cambridge: Harvard Univ. Pr., 1974. ISBN 0674823605

Lindberg, D. C., ed. Science in the Middle Ages. Chicago: Univ. of Chicago Pr., 1976. ISBN 0-226-48233-2

Shank, M. H., ed. The Scientific Enterprise in Antiquity and the Middle Ages. Chicago: Univ. of Chicago Pr., 2000. ISBN 0-226-74951-7

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