Why Did Modern Science Emerge in Europe?

The first lesson of my Netherlands trip began with a class on the "history of science."

More precisely, it began with what "science" is. "I will avoid using the word 'science' for any period before the Scientific Revolution. 'Science' did not yet exist then; we can call it 'natural knowledge.'" — Professor Cohan

This kind of "natural knowledge" existed in ancient China, and in ancient Greece too.

(Most of what follows is excerpted from my notes on the professor's lecture.)

The ancient Chinese tradition of "natural knowledge"

Zhang Heng of the Han dynasty discovered a link between the tides and the phases of the moon. The rise and fall of the Yangtze's tides gave him his data — but what led Zhang Heng to connect two things that seemed to have nothing to do with each other?

After taking office in the Northern Song, the erudite Shen Kuo discovered a spring containing a substance that, when added to an iron pot, turned the iron into copper — this was alum. What led Shen Kuo to such a discovery?

How did they come by such keen observations? — Through the theory of the Five Phases (wuxing).

The "Five Phases" were ancient China's worldview of nature. Metal, wood, water, fire and earth stand both for kinds of substance and for stages in how things unfold; seen one way they generate one another, seen the other way they overcome one another. And they cycle round again and again.

(Wow, how sophisticated!)

The Five Phases theory was one of the ways ancient Chinese scholars explained the world; another was "yin and yang."

It offered a flexible language that was ideal for talking about "balance" — not quantitative balance but dynamic balance: more complex sequences of growth, decay, mutual generation and mutual overcoming.

So the Chinese view of the cosmos was ever-changing and organic, always shifting with the spontaneous changes of its components. Understanding the world meant understanding not only substances but the relationships between them.

Of course, China was not the only civilisation to produce a complete worldview — another was Greek civilisation, but it differed from ancient China in many ways.

The ancient Greek tradition of "natural knowledge"

Ancient Greek "natural knowledge" developed into different schools: the schools of the four Greek natural philosophers, and the Alexandrian school. But this late-5th-century poem best captures pre-Socratic philosophy; it is seen as a major source of Western thought, and also as the point where Western and Chinese thought parted ways. "Being, how could it perish? How could it come to be? For if it came to be, it is not, nor is it if it is ever going to be. Thus coming-to-be is extinguished, and perishing unheard of."

The ancient Greeks of this period held that change is an illusion and that such an intermediate category cannot exist; by the time Athens became the centre of thought, the "phenomenon of change" (non-phenomenon) had become the focus of attention.

The four natural philosophers of the Greek city-state: 1. The school founded by Plato: change is confined to everyday appearances, and these appearances are hopelessly imperfect

2. Aristotle: "change" is the actualisation of what is potential

3. The Stoics

Change is a permanent state of tension 4. The Atomists

Change is the motion of tiny, unobservable particles

What do these four schools have to do with our real lives? — Not much, but all four are first-principles thinking. Each school's structure of knowledge is comprehensive and derived from general knowledge, yet fragmentary when it meets reality; examples serve almost no purpose beyond illustrating the a priori foundations.

Another mode of natural knowledge: Alexandria, the House of the Muses, became the city of learning for ancient Greece and Rome

Euclid's Elements brought together the achievements of generations of Greek mathematicians; its flaws were not discovered until the 19th century

This was demonstrable mathematics: even the most self-evident theorems received the most rigorous proofs

Music, light, the equilibrium of solids and liquids, planetary orbits — all were highly specialised fields of study,

and their practitioners were not only the greatest mathematicians of ancient Greece;

there was also Archimedes' fundamental theorem on equilibrium

As Ptolemy said: the link between the real world and mathematics is very weak; Alexandrian mathematics had almost nothing to do with reality

The aim of the Athenian disciplines was to "explain phenomena," to give phenomena underlying principles so they could be understood

Every philosopher would pick the examples from reality that best suited him

Qualitative rather than quantitative explanation — that was the natural philosophers' goal

Alexandria's goal was different

Ancient Greece: first principles are the core of everything vs. Alexandria: utterly indifferent to first principles,

they didn't want to explain, only to determine and analyse — not as illustration but as the starting point for mathematical analysis; this kind of research ran in one direction only.

It sought no connections, let alone a place within a whole

Any educated person could discuss philosophy, but mathematical discussion required training.

Looking at the big picture:

the ancient Chinese way emphasised observation and practice, grounded in observable phenomena and understood through the Five Phases and yin and yang;

the ancient Greek way argued in the most anti-empirical way people could conceive of. Both the Greek and the Alexandrian modes carried an epistemological flavour and involved a process of abstraction.

Here is the interesting part: why was it not ancient China's empirical method but the ancient Greek schools — whose modes of knowledge were far removed from practical use — that evolved into modern science? And a science capable of changing the world in unimaginable ways, too. "Think back to the first time you met your future spouse and it becomes very clear: many things in life have their own 'inner logic,' while others are simply 'how chance would have it.' World history is shaped by a mixture of this 'inner logic' and 'happy coincidence.'" — Professor Cohan

How "natural science" turned into "modern science"

It happened in the 15th century...

1. The key word is "transformation," especially "transformation of thought."

Large systems of thought lose their freshness after a very short initial period. Once the founding phase is over, followers keep repeating the founders' ideas, seek variation through competition with one another, and pass the founders' ideas on to the young in the most convenient way.

Was there any chance of renewal? Could China's organic change and Athens' worldview look at long-settled old questions in new ways?

In the West: exchange through hand-copied texts and with rival schools of thought — but how much vitality can there be in endless "protective" defence?

In the East: Han-dynasty China valued observation highly — but the chance of starting afresh and transforming was minuscule.

In short, once a discipline's golden age is over, it closes in on itself and grows stale.

2. A ruler's mood swings or change of interests could alter a scientist's fate.

Especially in imperial states, the ruler's attitude was key. Whether natural philosophers were valued was closely tied to "medicine" and "astronomical observation"; beyond the court, nobody cared.

Philosophy had no such problem, because every aspect of life called for philosophers.

3. In the pre-modern world, the understanding of natural science was unstable.

The peculiarities of Greek natural philosophy include: Athens was a priori, while Alexandria was computational. The two did not blend.

So where did the difference lie?

Neither in China nor in the Roman world could a new character emerge. If renewal can't come from within, it may come from without. Clashes between civilisations have been where novelty and innovation cluster in history: when foreign ideas, peoples and civilisations pour in, new opportunities arise.

Because of military, political and historical upheavals, Greece kept meeting new experiences. By comparison, ancient China saw no such transformation.

Because outsiders were rapidly sinicised as soon as they came in. After Christianity reached China in the late 16th century, the pursuit of natural knowledge, though it spread to Korea and Japan, did not develop well. Precisely because Chinese culture and institutions matured and solidified too early, its brilliant civilisation radiated out to its neighbours, but lacked opportunities for renewal within. The "organic worldview" that permeated the Chinese natural system held many "opportunities," yet in the end it was Greece that gave birth to science.

Athens and Rome were taken up elsewhere three times in succession, each time because of war.

The first time: at the end of the 7th century AD, natural philosophy was translated into other languages, and was not only adopted but given new meaning (for example, the role of light).

The second time: the Christian rulers of northern Spain reconquered the Muslim principalities, and the Toledo route in 1085 provided the opening — wandering scholars translated Greek texts from Arabic into Latin. These texts had circulated widely in Arab civilisation, and Aristotle's thought spread across Europe. The end result: the Aristotelian school achieved a monopoly. This was a period when it fitted Christian doctrine. The Aristotelian school began to innovate in the 13th–14th centuries.

The third time: Western Europe received the transmission of Greek texts, which happened when the Ottoman Empire conquered Byzantium. We still have the legacy of Greek texts preserved today: texts that Byzantium had kept for more than 1,000 years were carried to Italy. Plato's dialogues and Stoic writings reached Europe, and the Aristotelian school lost its monopoly; some had passed into medieval Europe and the Arab world, and mathematical texts were also translated into Latin, straight from the Greek originals, and together with the natural-philosophy texts reached the Catholic world — the European Renaissance, where Platonism and Stoicism got their chance.

The use and enrichment of ancient Greek thought resembled what happened in the Middle Ages (the mathematical astronomer Copernicus refined "heliocentrism"). This was an outstanding example of describing the "empirical world" less on the basis of epistemology and more through accurate description and a more empirical approach.

By the early 16th century,

the three modes of natural knowledge (Alexandrian, European empiricist, Platonic), through other procedures of testing, bound science more tightly to the real world. Empirical description and measurement turned into experiment. These three parts formed the beginning of the "Scientific Revolution."

Then came the "Scientific Revolution"...

It was Christiaan Huygens (1629–1695) tackling natural phenomena with mathematics and experiment;

it was the arrival of Galileo (1630s);

it was Descartes' revolutionary transformation of the Athenian school;

it was Huygens (1629–1695) and his earth-shattering words: no scientific conclusion is beyond doubt. In the past, China's unified philosophy, Athenian philosophy and Islamic theory — so many of these theories were considered settled "once and for all," with room for innovation only in very local corners.

But science's understanding of nature is a never-ending exploration. Every scientist must spare no effort in testing whether their conclusions are right; most of the time this includes finding the weak links in their own conclusions and designing ingenious experiments to see whether the conclusions hold.

Gradually, scientists who were good with their hands came on the scene too, and Huygens was one of them: he designed and improved telescopes and microscopes, improved Galileo's pendulum... In short, I love his scientific style — "this is very interesting, but I can do better." Why did science emerge in Europe?

As Professor Cohan said: "That science developed in Europe may have been accidental, a stroke of luck; it was not bound to happen."

This class pulled me out of science itself to look at the relationships between civilisations and between sciences.

Through military, political and historical upheavals, Chinese civilisation survived as one continuous, unbroken civilisation, successfully withstanding the Mongols — very different from Greek and Roman civilisation, whose world ended with barbarian invasions. A civilisation is also fragile and must embrace innovation and revolution, which are indispensable to modern science. But if a civilisation is strong, stable and sustainable, it finds it hard to embrace revolution and innovation, and so it misses certain opportunities. We should try our best to understand the "inner logic" of things, but also accept the surprises — and the helplessness — of "chance encounters." BTW, the Q&A session left a deep impression on me.

First of all, it was not exciting at all. Whatever the students asked, the professor either answered a different question, spoke in a very uncertain tone, or simply said he didn't know. This was very different from the lively Q&As I'd seen before.

But it was precisely these answers that showed me the rigour of real scholarship: every step of reasoning has to be tight; you can't answer just for the sake of answering.

There was a kind of German-style rigour, awkwardness and endearing charm about it.

About the lecturer, Professor Hendrik Floris Cohen

Born in 1946, he studied history at Leiden University, served as director of the Museum Boerhaave in Leiden from 1975 to 1982, and since December 2006 has been Professor of Comparative History of Science at Utrecht University.

He loves the pipe organ and sport, and is passionate about popular science. His books include The Revolution in Physics, How Modern Science Came Into the World, Quantifying Music: The Science of Music at the First Stage of the Scientific Revolution and The Scientific Revolution: A Historiographical Inquiry. In 2008, his The Re-creation of the World: How Modern Science Came About (translated into Chinese by Zhang Butian) won the Dutch Eureka Prize.

Two or three hours of lecturing and the professor never paused once — it turned out he had written out a word-for-word script.

Again, that German-style rigour, awkwardness and endearing charm.

Even more fun: three years ago, three Dutch sinologists translated Dream of the Red Chamber, and Professor Cohan actually took time off to read the whole of this Chinese classic — and a year later he read it all over again.

When I was little, my mother used to say, "Girls shouldn't read Red Chamber," afraid it would make me too sentimental... As a result I've never finished it even once! And this Dutch grandpa has read it twice! How embarrassing...