science made real progress in Europe in middle ages. modern experts now recognise the later Middle Ages as laying the foundations for the Scientific Revolutio

Tim O'Neill, I have a M.A. in Medieval Literature ... (more)
430 upvotes by Quora User, Judy Levy Pordes, Quora User, (more)
Summary: This question is based on the common but erroneous belief that there was no scientific progress in the Middle Ages.  In fact, modern historians of science have long since shown this to be a myth and have gone on to show that far from being a scientific dark age, the Medieval period lay the foundations of modern science.

The Myth of the Scientific Dark Age

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Pierre Duhem - the pioneer of early science history

This question is based on the common misconception that the Middle Ages actually were a scientific dark age and that there genuinely was "little real progress" in what we call science.  This is the popular conception of the period and pretty much how most people understand things - nothing much happened in science, or "natural philosophy" in the Medieval period until the Renaissance changed everything and the Scientific Revolution began.  But this idea is no longer accepted by modern historians of science and the later Middle Ages is actually now seen as a period in which there was not only the most scientific inquiry since the ancient Greeks but also the period in which the intellectual foundations of true, modern, empirical science were laid.

The standard view of the Middle Ages as a scientific wasteland has persisted for so long and is so entrenched in the popular mind largely because it has deep cultural and sectarian roots, but not because it has any real basis in fact.  It is partly based on anti-Catholic prejudices in the Protestant tradition, that saw the Middle Ages purely as a benighted period of Church oppression.  It was also promulgated by Enlightenment scholars like Voltaire and Condorcet who had an axe to grind with Christianity in their own time and projected this onto the past in their polemical anti-clerical writings. By the later Nineteenth Century the "fact" that the Church suppressed science in the Middle Ages was generally unquestioned even though it had never been properly and objectively examined.

It was the early historian of science, the French physicist and mathematician Pierre Duhem, who first began to debunk this polemically-driven view of history.  While researching the history of statics and classical mechanics in physics, Duhem looked at the work of the scientists of the Scientific Revolution, such as Newton, Bernoulli and Galileo.  But in reading their work he was surprised to find some references to earlier scholars, ones working in the supposedly science-free zone of the Middle Ages.  When he did what no historian before him had done before and actually read the work of Medieval physicists like Roger Bacon (1214-1294), Jean Buridan (c. 1300- c. 1358), and Nicholas Oresme (c. 1320-1382) he was amazed at their sophistication and he began a systematic study of the until then ignored Medieval scientific flowering of the Twelfth to Fifteenth Centuries.

What he and later modern historians of early science found is that the Enlightenment myths of the Middle Ages as a scientific dark age suppressed by the dead hand of an oppressive Church were nonsense.  Duhem was a meticulous historical researcher and fluent in Latin, meaning he could read Medieval scientific works that had been ignored for centuries.  And as one of the most renowned physicists of his day, he was also in a unique position to assess the sophistication of the works he was rediscovering and of recognising that these Medieval scholars had actually discovered elements in physics and mechanics that had long been attributed to much later scientists like Galileo and Newton.  This did not sit well with anti-clerical elements in the intellectual elite of his time and his publishers were pressured not to publish the later volumes of his Systeme de Monde: Histoire des Doctrines cosmologiques de Platon à Copernic - the establishment of the time was not comfortable with the idea of the Middle Ages as a scientific dark age being overturned.  Duhem died with his painstaking work largely unpublished in 1916 and it was only the efforts of his daughter Helene's 30 year struggle for her father's opus to see the light of day that saw the whole 10 volume work finally released in 1959.

By then Duhem was no longer alone in seeing the idea of the Middle Ages as a period of no science as a baseless myth.  The American historian of science Lynn Thorndike had followed the same trail as Duhem and came to the same conclusions that Medieval scientists had been wrongfully ignored and neglected since the Enlightenment, largely for political and ideological reasons.  In his eight volume History of Magic and Experimental Science (1923-1958) he too found that science in the Middle Ages was remarkably wide-ranging, speculative and highly sophisticated.  These pioneers in the field of early science history have now been followed by a long list of historians of the subject that have made this neglected period in scientific history even more clear.  Current leading scholars in the field such as David Lindberg, Ronald Numbers and Edward Grant have revolutionised our understanding of how the scientists of the Middle Ages built on the work they inherited from the Greeks and Arabs, advanced knowledge further and laid the foundations of modern science as we know it. 

Grant's ground-breaking 1996 book The Foundations of Modern Science in the Middle Ages shows in detail that the Scientific Revolution of the Seventeenth Century simply could not have happened if western European scholarship had remained as it had been prior to the early Twelfth Century, or even if it has stayed as it had been in the later Third Century.  It took not just the scientific advances but the intellectual changes of the later Middle Ages to set the scene for Galileo and Newton.  Rather than being a dark aqe, the high Middle Ages made true modern science possible.  More recently, James Hannam's God's Philosophers: How the Medieval World Laid the Foundations of Modern Science (2009) has presented a critically-acclaimed popularisation of modern scholarship on the subject, in an attempt to try to correct several centuries of prejudice and error that persists in the popular imagination.

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The Actual Scientific Dark Age

Of course, there certainly was a period in which western natural philosophy did stagnate and then languish and in which the whole scientific tradition of the Greeks and Romans was in danger of being lost.  Later Hellenic and then Roman scholars inherited the work of the Greek proto-scientists of the Fourth and Fifth Centuries BC and built on it.  By the First Century AD Roman scholars tended to read Greek and so could read the works of Aristotle and Archimedes in their original languages, but there was also an increasing tradition of encyclopaedic collections of summaries and key points from earlier Greek works which tended to be compiled in Latin.  The scholars of the First and Second centuries added some major contributions to science, especially Ptolemy (astronomy and mathematics) and Galen (medicine), but many Roman scholars made do with the Latin summaries and encyclopaedias for their grasp of earlier work.

In the Third Century, however, there were major social and political upheavals that interrupted many aspects of Roman life, including scholarship, with profound later consequences.  The Empire entered what is now called "the Military Anarchy", where rival emperors rose and fell in rapid succession and the Empire was racked with decade after decade of civil war and political oppression.  The weakened Empire suffered from invasions by the newly resurgent Sassanian Persians and by larger and more aggressive federations of Germanic barbarians. Cities that had been peaceful for centuries began constructing defensive walls, resources that once went into buildings and public works went into endless wars and at one point the Empire even split into three parts.

A form of stability was imposed by a new kind of more centralised and more monarchical emperorship, economic reforms and an overhaul of the army and the Imperial administration by Diocletian and his successors, but parts of the Empire never fully recovered, especially in the west.  Intellectual life and education, which had been badly disrupted in the long century of chaos, certainly did not regain its former strength and in the west fewer and fewer scholars were literate in Greek.  As a result, works that were only available in Greek, especially technical, philosophic and detailed scientific works, were read and copied far less and began to be neglected.  Greco-Roman science was increasingly preserved only in the popular Latin encyclopaedic tradition rather than studied in detail via the original Greek works.

By the Fifth Century the administrative division between the Latin-speaking Western Empire and the Greek-speaking Eastern Empire became permanent and then became a political divide.  The weaker, poorer and more vulnerable Western Empire did not even survive the century, with its final collapse coming in 476 AD after another century of civil wars, invasions and spiralling decline.  What followed was centuries of invasions, fragmentation and chaos, with few brief periods of stability and centralised authority.  The faltering intellectual tradition, which had already been in decline since the late Second Century, languished to a low ebb.

The institution which managed to keep this faltering tradition from dying out altogether during these centuries of barbarian invasion and disintegration was actually the one the Enlightenment myth (wrongly) blames for causing the decline in the first place.  The Christian church came to hold political power when the decline in learning in the west had been under way for over a century, and so could not have been its cause.  Initially Christianity was ambivalent toward Greek philosophy and learning, but prominent Christian thinkers who had been trained in philosophy could see it as something to be embraced.  God, they argued, was a rational intelligence and had created the universe along rational lines.  It made sense, therefore, that humans could and should use reason to understand his creation.  Clement of Alexandria argued that just as the Jews had been given a divine gift of special religious revelation, so had the Greeks been given a gift of rational analysis.  Both were to be embraced and used.

So when the Western Empire collapsed, the Church had long since come to terms with Greek philosophy and science and found ways to incorporate both and reconcile them with their religion.  And it was Christian scholars who saw that the decline of Greek literacy in the west meant much of the original works of Greek learning were being lost.  Cassiodorus and Boethius both tried to preserve key works by translating them into Latin.  Boethius was executed before he could complete an ambitious plan to translate all the works of Aristotle, but he did manage to translate most of the key works on logic - something which meant that logic and therefore reason took a central role in early Medieval education, even in the darkest centuries of the chaos.  The seeds of the Medieval revival of science lay in that stroke of luck.

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The Medieval Enshrining of Reason

One writer has compared the long road back from the intellectual catastrophe of the collapse of the Western Roman Empire on learning in western Europe to people after a nuclear holocaust trying to revive modern science with nothing but a few volumes of the Encyclopaedia Britannica and a copy of Bill Bryson's A Short History of Nearly Everything.  Scholars in the Eighth or Ninth Centuries had just enough fragments of information to know that they had barely anything at all but not enough to begin reconstructing what had been lost.  What is interesting is what they did with the bits they had - they revered them.  These ancient writers, mostly pagans, were held up as all-knowing authorities and what elements of their works did survive were studied with immense reverence and painstaking scrutiny.

This meant particular attention was paid to one of the few areas in which a reasonable number of works had survived - logic, or "dialectic" as it was known.  A grasp of logic was central to Medieval education and a student had to master it, via Boethius' translations of Aristotle and other works, before they could tackle any other subjects.  This had the curious effect of enshrining reason as the key to all knowledge - a development completely at odds with the popular view of the Middle Ages and the Medieval church in particular as being fixated on unquestioned dogma and irrational superstition.  There were certainly things that these Medieval scholars accepted on faith but they increasingly came to feel they could also arrive at them, and all kinds of other forms of understanding about the universe, via reason.  In a strange way, the loss of so much Greek philosophy actually focused attention on the elements that had survived and had the effect of enshrining reason at the heart of Medieval thought in a way not seen before. 

By the Eleventh Century the waves of Avar, Magyar, Saracen and Viking invaders had begun to recede, Europe had recovered economically and stabilised politically and was actually on the brink of a period of outward expansion. At the same time there was an expansion of literacy and interest in learning and an increasingly acute awareness of the loss of ancient learning and what scholars of the time lamented as Latinorum penuria ("the poverty of the Latins").  Exactly how intellectually poor the Latin west was is illustrated by an exchange of letters between two early Eleventh Century scholars, Ragimbold of Cologne and Radolf of Liege, about some mathematical problems that would not bother a high school student today.  Here were two clearly intelligent men who were seen as leading scholars of their day (the letters were copied and widely circulated) competing to solve some basic geometry problems but being forced to do so using scraps of geometry from old Roman surveying manuals and from a Sixth Century encyclopaedia that did little more than define a few terms.  It's an illustration both of how much had been lost in the cataclysm and how eager people were to recover lost learning.

The idea that the cosmos was rational and could be analysed via reason was certainly resisted by some conservatives, but a new guard of scholars came increasingly to the fore, including William of Conches, Honorius of Autun, Bernard Silvester, Adelard of Bath, Thierry of Chartres and Clarenbold of Arras.  William of Conches wrote with scorn of those who were suspicious of this worship of reason and rational analysis:

Ignorant themselves of the forces of nature and wanting to have company in their ignorance, they do not want people to look into anything; they want us to believe like peasants and not ask the reason behind things .... But we say the reason behind everything should be sought out!
(William of Conches (c. 1090-1154 AD), Philosophia mundi)

Intellectuals like William were increasingly attracting communities of students and gathering together with these students to share ideas, laying the foundations of the schools that were to become universities.  The stage was set for a genuine revival and flowering of learning, all Europe still lacked were the lost books of the Greeks and Romans.

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The New Learning and the Universities

By the early Eleventh Century European scholars were not just aware of how much western Europe had lost, but they were also aware that many of these works survived and could be regained.  They used the phrase Latinorum penuria because they knew there were others who were not so poor - namely the Greeks and the Arabs.  With a reviving western Europe now expanding militarily in all directions, it became easier for eager scholars to get access to these works and redress the balance.  The capture of the great Muslim centre of learning in Toledo in 1085 led many scholars to Spain in search of lost books and the Norman conquest of Sicily in 1091 opened up libraries of Arabic, Hebrew and Greek literary treasures.  And by the Twelfth Century scholars flocked to Sicily, southern Italy and Spain to translate these books into Latin and bring them home.  One of them was a young Englishman, Daniel of Morely:

I heard that the doctrine of the Arabs, which is devoted almost entirely to the quadrivium, was all the fashion in Toledo in those days, I hurried there as quickly as I could, so that I could hear the wisest philosophers of the world … Eventually my friends begged me to come back from Spain; so, on their invitation, I arrived in England, bringing a precious multitude of books with me.

Over the next two centuries many more "precious multitudes of books" made their way north to the schools and burgeoning universities of Europe and "new" Greek learning began to flood into Europe at precisely the point where the intellectual culture there was ready for stimulation.

What is remarkable is which books the translators concentrated on.  There was no shortage of Orthodox Greek theological works or even ancient Greek and Roman plays and poems available in Sicily and Spain, but these were generally ignored.  The eager scholars from the north concentrated overwhelmingly on works on mathematics, astronomy, physics, logic and philosophy as well as medicine, optics and natural history.  They were not interested in plays and poems (leaving them to be "rediscovered" later by the humanist scholars of the Renaissance) - these Medieval scholars were interested in the fruits of reason: science, logic and philosophy.

And the impact of these recovered works and the works by later Greek commentators and by Arabic scholars that accompanied them, had a revolutionary impact on the new network of universities that began springing up all over western Europe.  These new centres of learning took the scholarly framework of the old cathedral schools' curriculum based on the "seven liberal arts" but combined it with the structure of craft and merchant guilds (which is where the name universitas came from as well).  As in the guilds, students had to choose to work under the guidance of a "Master" and serve a long, structured and scrutinised apprenticeship and then pass a series of tests and oral examinations before being judged a "Master" himself and finally going on to become a "Doctor" or teacher.  This structure, hierarchy and rigorous testing made the Medieval university very different to similar-seeming schools in the Islamic world or the academies of ancient Greece.

The other radical and crucial novelty in the university system was the way advancement and prominence in this system was not gained merely by mastering material from key texts, but by disputation and debate using set rules of formal logic.  Masters and doctors maintained their positions and their reputations (and therefore their incomes from students) by their ability to win debates, often throwing open the floor to all comers.  And brilliant students could rise quickly in reputation and renown by taking on these masters and beating them.  At least twice a year a university would hold a quodlibeta - a multi-day tournament of rigorous logical disputation where anyone could propose and defend any position on any subject at all.  Often highly radical, controversial, paradoxical or even heretical idea were presented and participants had to defend or attack them using logic and reason alone.The idea of a rational free-for-all where the finest minds of the time used reason alone to bat around ideas like "God is in fact evil" or "the universe had no beginning in time" certainly does not fit most people's ideas of the Middle Ages, yet this was a regular event in Medieval universities.

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The Medieval Proto-Scientific Revolution

In this new environment of revived ancient learning, rigorous rational analysis and vigorous debate and investigation, Medieval Europe saw the first real flowering of scientific innovation since the ancient Greeks.  Developing ideas proposed by earlier Arabic scholars like Al Battani, Robert Grosseteste proposed that scholar should not only derive universal laws from particulars and then apply laws to particular cases (Aristotle's "principle of induction), but they should also use experiment to verify the particulars.  Roger Bacon developed this idea further, proposing a method based on a repeated cycle of observation, hypothesis and experimentation.  Both men applied this method to the study of optics, the physical nature of light, the function of the eye and the nature of lenses.  It was this analysis, which was an area of science Medieval scholars found particularly fascinating, which seems to have led to the invention of eye-glasses.  Bacon also described the construction and function of a telescope, though it's unclear if he actually built one.

With the Medieval development of the underlying scientific principles of observation and repeatable experimentation came probably the most revolutionary Medieval contribution to the rise of true modern science: the use of mathematics as a language to describe the physical world.  Aristotle and the Greeks had considered it bad practice to try to extrapolate from one discipline (like mathematics or geometry) to another (such as physics).  But with the development of more sophisticated ideas of reasoning from observation and induction in the Thirteenth Century, thanks to the likes of Grosseteste and Bacon,  Fourteenth Century scholars hit on the idea of making observation and induction more precise by using mathematics as the language of physics.  Thomas Bradwardine wrote:

[mathematics] is the revealer of every genuine truth, for it knows every hidden secret and bears the key to every subtlety of letters.  Whoever, then, has the effrontery to pursue physics while neglecting mathematics should know from the start that he will never make his entry through the portals of wisdom.

Bradwardine was one of a group of scholars who worked on key issues in physics using this new insight.  Along with William Heytesbury, Richard Swineshead and John Dumbleton and building on the work of William of Occam and Walter Burley, these Oxford University scholars became known as the Merton Calculators and they lay the foundations for modern physics as we know it.

Most importantly, they overturned the earlier Greek conception of motion by distinguishing kinematics from dynamics.  Aristotle and other Greek scholars had seen motion purely as a matter of external force, whereas the Merton scholars looked at the persistence of motion via impetus - measurable by material volume and velocity.    This laid the foundations for the later key understanding of momentum, but also allowed them to formulate the Mean Speed Theorum.  This was long attributed to Galileo, but it is now clear that it was the Merton Calculators who discovered and proved this principle long before Galileo was born (there is also some evidence that he read of their work and presented the idea as his own without attribution).

These ideas about impetus allowed later Medieval scholars to develop physics further and begin to apply them to astronomy.  So Nicole Oresme was able to use impetus to show that most of the ancient Greek objections to the possibility of a revolving earth were invalid.  He still believed that the earth was stationary on other grounds, but his arguments were later taken and used by Copernicus in the development of heliocentrism.  Orseme, Jean Buridan and Nicholas of Cusa were also able to show how impetus is a constant motive power that is corrupted or halted only when it encounters some form of resistance.  This allowed Medieval physicists to set aside the Greek idea that celestial motions took place in some incorruptible heavenly realm where earthly physics did not apply and meant people could start applying principles discovered on earth to the motions of the heavens.

The idea that Copernicus, Kepler, Galileo and Newton all developed ideas that had no roots in the thinking of the two or three centuries that preceded them is clearly ridiculous, yet this has been the claim of the post-Enlightenment myths about the Middle Ages.  Objective modern research, however, has shown that without the work of people like Grosseteste, Bacon, Occam, the Merton scholars, Oresme and Buridan the "Scientific Revolution" would never had occurred.  That revolution had Medieval foundations.

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The Church's Suppression of Ideas?

Actually, nothing of the history detailed above sits neatly with the idea of the Medieval Church as a violent and intolerant theocracy that immediately consigned anyone with the whiff of a new idea to the flames.  In fact, the parameters for speculation and investigation into the nature of the physical world were quite wide, because the Medieval Church considered the cosmos to the the rational product of the rational mind of God and that humans were given reason partly so they could apprehend and investigate the universe rationally.

This is why Thomas Aquinas spent years and many millions of words painstakingly applying the rational principles of ancient Greek dialectic to Christian theology in an attempt at showing that all the key ideas of Christian belief could be arrived at by pure reason. It is also why the quodlibeta debates at Medieval universities were such open free-for-alls where all kinds of radical and even heretical ideas could be proposed to see if they stood up to logical analysis.

The Medieval Church also did not insist on a purely literal interpretation of the Bible (fundamentalist literalism is a modern and largely American Protestant idea).  This meant that it had no problem with seeing aspects of the Bible as purely allegorical and with the exploration of how their symbolic truth relates to the real world.  Most people who think of the Medieval period as one where Biblical literalists suppressed original thinking though fear would have a hard time explaining, for example, the work of William of Conches.  Way back in the Twelfth Century this scholar, based at Chartres Cathedral, accepted that his audience already understood the creation story in Genesis to be symbolic and went on to interpret it "according to nature'.  He proposed how natural forces set in motion by God brought about the form of the heavens and earth as we have them today.  He went on to talk about life arising from the primordial mud by the natural action of heat and how it developed from simple early forms.  He even talks about how man arose in the same way and how, in theory, some other species of man could arise via natural processes in the same way.

All these very modern-sounding (even Darwinian) ideas were accepted by Medieval scholars without the slightest problem and the Church had no difficulty with them either - indeed, William of Conches, like all other Medieval scientists - was a churchman.

The closest the Church came to suppressing science in any way was when, in reaction to some of the ideas being debated in the University of Paris at the height of the rediscovery of Aristotelian learning in the Thirteenth Century, the Faculty of Theology attempted at putting some limits on what could be discussed by the Faculty of Arts.  In 1210, 1270 and again in 1277 the Pope, at the request of the Parisian Theology Faculty, published lists of ideas proposed by Aristotle or implied by his philosophy that were contrary to Christian doctrine and so were forbidden.  What is remarkable about this is, firstly, how little in Aristotle etc was actually proscribed by these Condemnations.  Secondly, it's remarkable how ineffective the Condemnations were.  They only applied to Paris, whereas discussion of all these topics continued at Oxford and other universities unaffected.  And, as the fact that they had to be repeated twice indicates, they were widely ignored anyway.  They also had another effect - by arguing that Aristotle was actually wrong on several key points, they stimulated a more critical examination of the Greek philosopher's work which led to several of his idea being critically analysed and found to be incorrect (eg the idea that a heavy object falls faster than a lighter one).  IN a strange way, the Condemnations failed to suppress science and actually helped to stimulate it.

The fact is that the idea of the Church suppressing science and rational analysis of the physical world is a myth.  Not one Medieval scholar was ever burned, imprisoned or oppressed by the Medieval Church for making a claim about the physical world.  This why the modern proponents of the myth always have to fall back on an exceptional and post-Medieval example to prop up this idea: the Galileo case.

Conclusion

So the claim that "science made little clear progress in Europe in the Middle Ages" is based on a profound ignorance of the period and depends on a prejudiced myth that is without any basis.  Once Medieval Europe recovered from the chaos that followed the fall of Rome, it quickly revived the ancient tradition of natural philosophy that had been languishing since Roman times.  Medieval scholars engaged in a remarkable process of examining the physical universe using reason and logic and, in doing so, developed principles that were to become the foundations of modern science proper.  And they applied these principles in ways that corrected errors the Greeks had made and did the ground work for the later discoveries in physics and astronomy that made up the beginning of the Scientific Revolution.  While people with no detailed knowledge of modern studies in the history of science still cling to Nineteenth Century myths about the Church suppressing science, it is now clear that without the flowering of speculation and analysis in the period from the Twelfth to the Fifteenth Century, western science would never have arisen at all.

Bibliography

David C. Lindberg, The Beginnings of Western Science, 600 B.C. to A.D. 1450 (1992)
David C. Lindberg, Science in the Middle Ages (1978)
Ronald Numbers, Galileo Goes to Jail, and Other Myths about Science and Religion (ed.) (2009)
Edward Grant, The Foundations of Modern Science in the Middle Ages (1996)
Edward Grant, God and Reason in the Middle Ages (2001)
James Hannam, God's Philosophers: How the Medieval World Laid the Foundations of Modern Science (2009)
  
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Paul King, Computational Neuroscientist, Softwar... (more)
7 upvotes by Andy Lee Chaisiri, David Joyce, Nancy Na, (more)
The reason for the appearance of scientific inactivity in the middle ages may be partly a contrast effect.

There was such a flurry of public intellectual progress during both the period of Ancient Greece that preceded it, and the renaissance that followed it, that one is left with the impression that science in the medieval era was "held back" and uneventful.

Science in the medieval era (5th - 15th century) took the form of steady progress (as Tim O'Neill observes) within isolated scholarly communities.

The Renaissance (14th - 17th century) unleashed numerous mutually reinforcing social effects that dramatically amplified the pace of progress:
Invention of the printing press allowing faster dissemination of discoveries (15th century)
Systematization and expansion of the university system (16th century)
Momentum from persuasively demonstrated revisions to the natural order of the universe (Copernicus, Galileo, Newton) (16th-17th century)
Formation of scientific journals and scientific research societies (17th century)
Systematization of the scientific method (17th century)

The formalization, systematization, and acceleration of communication that created the collective project of science increased and pace of discovery to such a degree that the middle ages look dark by comparison.

This contrast effect is further enhanced by the progress made in math and open intellectual discourse in Ancient Greece (8th century BC - 6th century AD). The slower paced middle era is sandwiched between two eras of public progress, thus appearing even more disproportionately "dark".

Phil Jones, Still figuring it out
6 upvotes by Phil Darnowsky, Anthony Tauro, William Burnes, (more)
To add only a tiny thought to Tim O'Neill's excellent answer, the mediaeval technologists gave us  :

- the plough. (Able to cope with heavy Northern European soils, turning Northern Europe from relatively unproductive to relatively productive. Creating a huge new surplus of wealth in the north.)

- extraordinary advances in architecture : cathedrals.

- the printing press. (Don't forget this may have launched the Renaissance, but it was mediaeval minds that come up with it.)

- clocks (and clockwork). The beginnings of automatio