A brief and incomplete history of science

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Imagine you came across an abandoned time machine while going for a walk in the forest. You step in and whooooosh! You’re taken back to medieval times – what could you tell them about the world? Yes, they should boil their water and perhaps not put the toilets next to the well.

Yes, you could tell them about gravity but they probably already knew that what goes up must come down.

Yes, you could tell them about evolution but they already knew about breeding animals. Any talk about dinosaurs and ape ancestry would only get you a job as a jester.

Unless you’re one of the rare people who know how a steam engine works or who have memorised calculus, it’s unlikely that you could really tell them much that would improve their lives.

And yet you know so much that they didn’t – that the world goes around the sun, that diseases are caused by bacteria and viruses, that blood circulates around our bodies – but you wouldn’t be able to convince people in 1300 of any of this.

Most of what we think we know is mostly secondhand knowledge. Other people know it for us. We might know what electricity, for example, does – it charges our phones! – but most of us would be hard pushed to say what it is. Telling our ancestors that it’s the zappy stuff that makes things work wouldn’t be much of an explanation.

But how do they ever work anything out in the first place?

The ancient Greeks were great at guessing

The last person to be executed under suspicion of being a witch in Britain was Janet Horne in 1722.

In 1801, the British polymath, Thomas Young, demonstrated that light behaves as a particle and a wave, laying the foundations for quantum science.

How did we go from killing people on the basis of superstition to deciphering the nature of light in 79 years?

Knowledge probably began with trial and error. That plant killed the last person who ate it – it’s probably poisonous. As such, progress was painfully slow. It took tens of thousands of years before we even learned how to melt copper and tin together to make the more useful bronze.

But while civilisation began with the introduction of agriculture 10,000 years ago or so, when we trace the roots of our thirst for knowledge we inevitably focus on the Greeks. The ideas and philosophy of Ancient Greece influence us still today.

Their astronomers observed the stars and made a pretty good calculation of how wide the Earth was. Their philosophers laid down the basis of logic and rational argument. They laid down some of the foundations of mathematics and music.

They got plenty wrong though. The Greek physician, Galen, laid the foundations of medicine that were followed for a millennia and a half. He didn’t know that blood circulated through the body, for instance and his misconceptions were blindly followed for close to 1500 years.

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The Greeks (like many modern day hippies) thought that the world was made up of 4 elements – earth, water, fire and air. We now know there are 118.

But what they did do was ignite a tradition of thinking about the world. They used reason to ask questions about the nature of time, the building blocks of matter, about the relationship between animals and plants.

Sometimes they came tantalisingly close to describing reality – Democritus in 5 BC, came up with the idea of atoms, tiny particles invisible to the eye and impossible to divide any further – he was wrong about that, of course but it was a remarkable guess.

But apart from the observations they could make with the naked eye and the maths they could scribble on papyrus, that’s what the ancient Greeks were limited to doing: guesswork. They didn’t have the tools to measure the world or a body of knowledge to help them understand the observations they were able to make.

After the Greeks, the traditional history has it that Europe entered the Dark Ages of mud, violence and superstition. For the next millennia or so there were few progresses in inventions or knowledge until the Renaissance began and the telescope was invented.

But that’s because in the West, the history of science has been told by..Western historians.

The truth is that science owes more to medieval Islam than it would like to admit.

Islam? What has Islam ever done for us?

One of the most amazing stories of history is the lightning spread of the Islamic Empire. In the year 610, Muhammed, a merchant from Mecca, had a mystic experience where he believed he saw an angel who gave him the first teachings of a new religion.

140 years later, the Islamic Caliphate stretched from the Spanish Pyrenees to the borders of China, ruling over 30% of the world’s population.

The intellectual, technical and cultural accomplishments of medieval Islam are mostly overlooked in the history books. It was in this time, for instance, that the art of making paper was perfected. This meant that knowledge could be shared in a way that it never had before.

The Arabs brought a much needed skepticism to the dogma of the Ancient Greeks and opened the doors to new intellectual discovery. Among other things, they revolutionised mathematics and the maths we do today is still based on their algebraic system,

The Arabs also moved science beyond trial and error and guesswork by pushing for theories to be confirmed by evidence and experiment: the basis for the scientific method.

In an age of windmills and water clocks, literacy and debate, it probably felt to people of the time that they were living in the Age of Discovery.

Then what happened?

Galileo

Medieval Islam usually gets a cursory nod from historians for having translated the original Greek manuscripts into Arabic (by way of Syriac) and keeping the torch of knowledge alive until it could be translated into Latin and the Europeans could get to work.

But one of the main things holding back thinkers of the day was religious belief.

When in the early 1600’s Galileo promoted the revolutionary idea that the Earth went around the sun he was pronounced a heretic by the Catholic Church and eventually sentenced to house arrest.

Why did the Church care about astronomical observations?

Because at various points in the Bible it’s suggested that the Earth stands still and the sun goes around it. How could the word of God be wrong?

But though religious persecution was a real threat for early scientists, belief itself was sometimes a bigger obstacle.

When, a contemporary of Galileo, Johanes Keppler, tried to work out the orbits of the planets he couldn’t make the numbers add up. He believed that the planets must move in perfect circles. God made the world and God was perfect…so circles it must be.

It was only when he allowed himself to imagine that God could be perfect but the universe that He had created might be imperfect that he made his breakthrough. Keppler made his calculations with the planets moving in ellipses instead and suddenly the maths worked out.

It’s tempting to imagine that the story of science is the tale of a few rational souls struggling against the superstitious tyranny of organised religion but in reality things were much more mixed up back then. Keppler, for instance, was personal astrologer to the Roman Emperor – he studied the stars and also believed they could tell us the future.

When Isaac Newton came up with the laws defining gravity he believed that he had found proof of God’s existence. Emissaries from the Church came to ask him if he could discover other laws for things like sin and grace, too.

The first scientists called themselves Natural Philosophers and it was only gradually that reason was able to stand up on its own two legs without the need of a religious worldview. In part, that happened when the emerging field of science began to come up with the inventions that changed the world. Anyone can have an idea but an idea that works gets a lot more attention.

Okay, so where did modern science come from?

Storytelling needs its heroes and villains. Galileo: hooray! Catholic Church: boo!

In reality, things were far messier than that. The history of science and invention is made up of a multitude of small insights and advances, adaptations and inspirations, all taking place over a very long time.

But progress is exponential.

As we moved into the 18th and 19th centuries, growing populations and economies meant there were more people to do science and the money to fund them. New inventions and materials meant that there were more things they could investigate and with greater efficiency.

And, as with any movement, each scientist inspired another. Each new discovery made the world seem like a place that could be understood by human minds. Whereas the Ancient Greeks could only hypothesise about the world, scientists could now put things to the test and use the results to make the world a better place.

Kazoom! The steam engine! Kabam! Anaesthesia! Hiyah! The smallpox vaccine.

We sometimes think that we live in a dizzy age of innovation where none of us understand the world around us but imagine someone born in 1750: in their lifetime they would have seen little glass suns  illuminating their cities, wires through which one could talk to people who weren’t there, little boxes that gave you music and told you the news, wagons that moved without horses and other ones that flew through the air!

But inventions were only part of the story. Science only really came together as a discipline in the 20th century with the formulation of the scientific method, peer-review journals and an international scientific community publishing in English.

Maybe in 100 years we’ll look back at this era of science with the same kind of gentle nostalgia we feel for the Ancient Greeks – just imagine, they had to actual experiments to find stuff out instead of asking AI! Wow, imagine trying to learn about the world in a lifespan of 80 years instead of 800…

Alternatively, of course it may be that the answer to Fermi’s Paradox (essentially, it goes: space is really big, where the hell are the aliens?) is that intelligent civilisations eventually develop enough science to wipe themselves out.

I prefer to be more opimtistic about the future of intelligence.