Welcome to the Deep Dive. Today we're going to
tackle a moment in history that is, well, arguably
one of the most important transformations ever.
It's a huge claim, isn't it? It is. We're talking
about the scientific revolution. And it's not
just about a few new discoveries. It's about
the moment humanity decided to, uh... fundamentally
rewrite the entire rulebook for how we know what
we know. I think it's the perfect way to frame
it. You know, people often compare it to the
Neolithic revolution. Right. When we learn how
to farm. Exactly. And that changed how we lived,
how we sustained ourselves. But the scientific
revolution changed how we understood reality
itself. It was a change in the mind. So our mission
today in this deep dive is to really get under
the hood of that shift, not just what was discovered,
but how the whole process of acquiring knowledge
was, well. reinvented. A total reinvention. And
it happened primarily in Western Europe over
a pretty specific span of time. Okay, so let's
put some guardrails on that. When historians
talk about this period, where do they draw the
start and end lines? Well, the traditional dating
book ends the whole era with two monumental sets
of publications. It kicks off in 1543. 1543.
And what happened that year? You get two foundational
texts published almost simultaneously that challenge
the old order in completely different fields.
It's an amazing coincidence, really. Okay. Lay
them on us. On the one hand, you have Andreas
Vesalius, who publishes the Humani Corporis Fabrica.
Which is? On the workings of the human body.
And it was a direct, visual, and frankly, brutal
assault on 2 ,000 years of... medical authority
held by the ancient physician Galen. So that's
the revolution in understanding ourselves, our
bodies. What was the other one? The other was
Nicholas Copernicus' De Revolutionibus on the
revolutions of the heavenly spheres. The big
one? The one that moved the Earth? The one that
moved the Earth. It proposed a sun -centered
system which flew in the face of, well, all of
Western cosmology going back to the Greeks. So
you have the microcosm and the macrocosm both
being turned upside down in the same year. An
incredible starting point. So if 1543 is the
disruptive beginning, where's the finish line?
What's the grand finale? The culmination, the
great synthesis, arrives in 1687. When? Isaac
Newton's Philosophia Naturalis Principia Mathematica.
The Principia? Of course. And when you frame
the era between Copernicus and Newton, you're
defining a period that saw this... This irreversible
break with what came before, with natural philosophy.
So the new science, as they called it, what made
it so new? It was more mechanistic. It was deeply,
fundamentally integrated with mathematics in
a way that had never happened before. And maybe
most importantly, it was completely dependent
on gathering new empirical evidence. So high
level, what was the significance of all this?
What really changed in the big picture? I mean,
science as we know it was born. It became its
own thing, an autonomous discipline, separate
from philosophy on one side and just tinkering
or technology on the other. It started to have
a purpose. A utilitarian purpose. Suddenly, the
goal of science wasn't just to contemplate the
heavens. It was to solve human problems, to make
life better. The rapid, accelerating accumulation
of knowledge that defines our modern world. It
all starts right here. To really get a feel for
what a revolution this was, we have to start
with what was being overthrown, the intellectual
foundation of Europe for centuries. The Aristotelian
tradition. I mean, it's hard to overstate how
completely it dominated every facet of intellectual
life. It was more than just a model of the planets.
It was a complete philosophy of reality. A complete,
coherent, and deeply intuitive one. It placed
the Earth, our world, right at the center of
everything. But it wasn't just a physical model.
It was a philosophical one that divided reality
into two totally separate realms. Okay, let's
start with our realm, the one we live in, the
terrestrial region. You said it was imperfect.
Imperfect is the realm of change, of decay, of
generation, and corruption. Everything here was
made of the four classical elements. Earth, water,
air, and fire. Right. And every single object
in this realm had a natural movement, a tendency
to go to its natural place. So a rock, which
is made of earth, naturally wants to go down.
Down toward the center of the universe, which
was the center of the earth. Water also moved
down. Air and fire, being lighter, their natural
movement was up, away from the center. So if
I throw that rock, I'm forcing it to do something
it doesn't want to do. Exactly. That's called
violent motion. It's temporary, it's forced,
and it requires a continuous external push. The
second you start pushing, its natural tendency
to just fall takes over again. It was all about
purpose, about teleology. But then you look up
past the moon and the rules of physics just change.
Completely. You've entered the celestial region,
the realm of the perfect. It was eternal. It
was unchanging. It wasn't made of earth, water,
air, or fire. No, it was made of a fifth element,
the ether. And because this realm was perfect,
its motion had to be perfect. And the only perfect
motion was... Uniform circular motion. Uniform
circular motion. The heavens were a series of
nested, crystalline spheres, all rotating eternally
and perfectly around the central Earth. This
sharp, absolute distinction between the messy,
straight -line motions on Earth and the perfect
circular motions in the heavens, that was the
bedrock. But there was a problem. The planets
don't always move in perfect circles from our
perspective. Sometimes they seem to slow down,
stop, and even go backward. Retrograde motion.
Yeah. And that was a computational nightmare
for the pure sphere model. And that's where Ptolemy
comes in, right? Trying to fix the math. Claudius
Ptolemy's Almagest is this monumental work of
ancient science where he formalizes the geometric
tricks you need to make the geocentric model
actually work, to make it predictive. Tricks
like epicycles. Epicycles, difference, eccentrics.
I mean, it gets incredibly complicated. Can you
break that down? What are we actually picturing
here? Okay, so imagine the main circle a planet
takes around the Earth. That's the difference.
But the planet isn't actually on that circle.
It's on a smaller circle, the epicycle. That
is itself rolling along the edge of the bigger
circle. So it's a circle on a circle. It sounds
like one of those spirograph toys. That's a fantastic
analogy. It is. And to make the predictions even
more accurate, the center of the main circle,
the deferent, might not even be the Earth. It
might be offset slightly. That's an eccentric.
So you're layering all these geometric fixes
on top of each other. You are, all to preserve
two things. The central Earth. And uniform circular
motion. The math was brilliant. It worked for
predictions. But the physical reality of it was
getting, well, very strained by the 16th century.
That sets the stage perfectly. But revelations
don't happen in a vacuum. You need technology.
You need infrastructure. And the key enabler
for this entire scientific awakening was invented
about a century before Copernicus. The printing
press. The printing press. It's almost impossible
for us to grasp the impact. It changed everything
about how knowledge was created, shared, and
validated. Before the 1440s, there was no mass
market for a scientific book. Religious texts,
sure, but not science. And if you were trying
to copy a book by hand, especially one with diagrams,
you'd get errors. Scribal errors, misinterpretations,
things left out. The errors would compound with
every new copy. But printing allowed for the
accurate mass reproduction of everything. Text,
maps, and crucially anatomical drawings. So it
wasn't just about making knowledge cheaper. It
was about making it consistent, standardized.
Absolutely. A researcher in Padua could be looking
at the exact same edition of a text by Archimedes
as a scholar in London. They could compare their
own new observations to a stable, reliable foundation.
You didn't have to, as one source put it, always
start from scratch. And for a science like anatomy,
the visual accuracy must have been a revolution
in itself. A total revolution. They moved from
woodcuts, which were okay but would wear down
and lose detail with every printing. To what?
To engraved metal plates. These allowed for incredibly
precise, high -fidelity images that could be
reproduced thousands of times without decaying.
Permanent visual information. But even with this
new tech, mistakes could still happen. I read
that Galileo's first big publication had some
issues. That's a wonderful detail. When Galileo
published his Sedarius Nuncius in 1610, with
those stunning first telescopic drawings of the
moon. The ones that showed it had mountains and
craters, that it wasn't a perfect sphere. Those
ones. In the very first printing, the images
of the moon came out back to front. A printing
blunder. It just underscores that even the most
revolutionary content depended on a manufacturing
chain that was still, you know, figuring things
out. Now, we've set this up as a great break,
but you also mentioned that a lot of these pioneers
were actually very respectful of the ancients.
It wasn't a total rejection. And this is the
core of what historians call the continuity thesis.
It's not as simple as Aristotle bad, Newton good.
Figures like Copernicus, Galileo, Kepler, even
Newton himself. They were meticulous about tracing
ancient and medieval pedigrees for their big
ideas. They were trying to show they weren't
just making things up out of thin air. Precisely.
They were often reviving minority views from
antiquity that had been suppressed by the dominant
Aristotelian framework. Can you give us an example
of that? The heliocentric system itself. Copernicus
knew perfectly well that Aristarchus of Samos
had proposed a sun -centered system back in the
3rd century BC. So he was bringing back an old
idea, not inventing a new one. He was giving
it a rigorous mathematical framework it never
had before. Same with Newton. When he laid out
his laws of motion, he traced the concept of
inertia, the idea that a body in motion stays
in motion, all the way back to ancient atomists.
And he even credited his contemporaries in the
Principia, didn't he? He did. He makes a point
of saying that his three laws of motion were
already accepted by guys like Christian Huygens
and Christopher Wren. He saw his work as the
grand mathematical formalization of ideas that
had been sort of floating around for a long time.
The systematic rigor, though, That was new. That
was the revolution. Okay, so if the core ideas
had some ancient roots, then the real revolution
has to be in the process, the method. This move
from the book -reading philosopher to the hands
-on experimentalist. That's it exactly. The shift
in approach was just profound. Under the old
Aristotelian model, Observation was passive.
You'd go out and look for natural circumstances.
So you're just confirming what you already believe.
You're confirming the essence of a thing. If
you saw a weird plant, a mutation, you'd dismiss
it. It's an aberration, an imperfection that
tells you nothing about plantness. But the new
way of thinking flipped that completely. It said,
we don't wait for nature to show us its secrets.
We have to design experiments to force it to
reveal them. We have to manipulate it, put it
under stress. And this put empirical evidence,
the result you can see and measure, right at
the center of everything. John Locke really formalized
the philosophy behind this a little later on,
didn't he? He did. In his essay concerning human
understanding in 1689, he gives us the idea of
the tabula rasa. The blank slate. The blank slate.
The mind has no innate ideas. All true knowledge
comes from experience. Sensory impressions get
written on that tablet, and then our minds reflect
on them to build up knowledge. It's a foundational
idea for empiricism. So if Locke built the philosophical
house, Francis Bacon drew up the blueprints for
the method, the father of empiricism. Bacon's
ambition was just staggering. He wanted a complete
reformation of all knowledge, what he called
the instauratio magna the great instauration.
And his goal was explicitly? Practical. Utterly
practical. To advance learning in order to relieve
mankind's miseries. He had these two central
maxims. First, man is the minister and interpreter
of nature. Okay. And second, and this is the
crucial one, nature can only be commanded by
obeying her. You have to understand the rules
before you can use them. You have to submit to
the evidence first. It's a complete inversion
of the old way where you started with the philosophical
principle and tried to make the evidence fit.
And he proposed a whole new system of logic to
replace the old scholastic methods. Right. He
attacked the syllogism, which argues from general
premises down the specifics. Bacon wanted to
go the other way. Inductive reasoning. Inductive
reasoning. You start with specific, carefully
gathered facts, and from there you move upward
to axioms or theories, and finally to general
physical laws. And you do it through what he
called eliminative induction. Meaning you test
all the possibilities and eliminate the ones
that don't work. Exactly. You systematically
rule out hypotheses until only the correct one
remains. And he was very focused on... all the
ways our own minds can trick us. Oh, absolutely.
He talked about the idols of the mind, these
false notions and biases we all have that get
in the way of seeing things clearly. He was particularly
critical of traditional philosophy, saying it
was too obsessed with words and debate. It made
science, in his words, sophistical and inactive.
He wanted results, inventions. Yes. For him,
the whole point of science was to better human
life by producing new inventions, which he saw
as new creations and imitations. divine works.
It gave science a kind of moral purpose. It's
important to remember, though, that for all his
genius about the method, he wasn't always right
about the science of his own day. That's a fantastic
point. He was a visionary for the process, but
he actually rejected a lot of correct theories.
He dismissed Copernicus's heliocentrism, Kepler's
laws, even William Gilbert's work on magnetism.
So Bacon gives us the theory of the scientific
method. How did people actually start putting
it into practice? Well, Bacon's description is
great. He said you first have to light the candle.
That's your hypothesis. And then you use the
candle to show the way, which means designing
your experiment to test it. And that's exactly
what you see in the work of pioneers like William
Gilbert. Gilbert published Emegiidae in 1600,
even before Bacon's big work. He was a true experimentalist.
A passionate one. He hated Aristotelianism. He
famously built a model Earth, a spherical magnet
he called a Torella. A little Earth. A little
Earth. And he used tiny compasses and needles
to meticulously map its magnetic field. And from
these experiments, he concluded that the Earth
itself must be a giant magnet, and that's why
compasses point north. The rigor of how he described
his experiments was hugely influential. But the
figure who really brings it all together, the
experiment and the math, is Galileo. Galileo's
the one. He makes a decisive, world -changing
claim. The laws of nature are mathematical. The
book of nature is written in the language of
mathematics. That's the quote. He said the universe
cannot be understood unless one first learns
to comprehend the language and interpret the
characters in which it is written, triangles,
circles, and other geometrical figures. It's
such a profound statement. It's saying reality
has a mathematical structure. An objective structure.
He even said that when it comes to the certainty
of mathematical propositions, human knowledge
equals the divine. Wow. And to make that work,
his experiments had to be precise. He needed
standardized measurements of time and distance,
things we take for granted, so he could make
reproducible comparisons and confirm his mathematical
laws. And once that door was opened, this idea
of mathematizing nature just exploded. It did.
But it required new mathematical tools. You get
Francois Viette introducing symbolic notation
to algebra in 1591, which makes it so much more
powerful. You get Descartes in 1637 linking algebra
and geometry with Cartesian coordinates. And
then the ultimate tool for describing a world
in motion. Newton's development of infinitesimal
calculus. It just opened up vast new territories
for analysis. The universe wasn't just observable
anymore. It was quantifiable. All of this, the
focus on parts, on motion, on math, it coalesces
into a new worldview. The mechanical philosophy.
Right. And this was the final death blow to Aristotle's
teleology. The old view had four causes, but
the most important was the final cause, the purpose.
Why a thing exists. Why it exists. What its goal
is. The mechanical philosophy just strips all
of that away. The universe is not an organism
with purposes. It's a machine, a giant clockwork.
And its parts are just inert. particles. Inner
particles or corpuscles. They have no goals,
no desires. They just move. And the only way
they move is by being hit by other particles.
Direct physical collision like billiard balls.
So no mysterious forces, no action at a distance.
Absolutely not. That was seen as a throwback
to magic and mysticism, which brings us to the
great paradox of the whole revolution. Isaac
Newton. Isaac Newton. Because when he introduces
his theory of universal gravitation, what is
it? It's an invisible force acting instantaneously
across the vast emptiness of space. It's spooky
action at a distance. It's the very thing the
mechanical philosophy was supposed to eliminate.
And his critics jumped all over it, calling it
an occult quality, a hidden magical power. How
did Newton deal with that? Very cautiously. It's
where his famous phrase, hypothesis non fingo,
comes from. I frame no hypotheses. Meaning he
wasn't going to guess why gravity worked. Exactly.
He said, look, the math works. The phenomena
prove that this force of attraction exists. That's
enough. I don't need a mechanical explanation
for its cause. But that wasn't a very satisfying
position for people. Not at all. And it was actually
his collaborator, Roger Coates, who provided
the philosophical out. In the preface to the
second edition of the Principia, Coates argued
that gravity was just another inherent power
of matter given to it by God, just like inertia
was. So it's just a fundamental property of the
universe. It's just a rule of the game. And by
the mid -18th century, that view was totally
accepted. It paved the way for all of modern
physics, which is full of field forces and action
at a distance. Okay, so we have the method, the
math. the worldview. But for this to stick, for
it to become permanent, it needed to be institutionalized.
This is maybe the most important part. Knowledge
needed a home. And the first one was the Royal
Society of London, founded in 1660. It grew out
of these informal meetings of natural philosophers,
right? At a place called Gresham College. And
they were hugely inspired by Francis Bacon's
vision of a cooperative research institute. They
even got a royal charter from King Charles II.
to be a college for the promoting of physical,
mathematical, experimental learning. A bit of
a mouthful, but says it all. And they appointed
a curator of experiments, Robert Hooke, whose
job was to perform experiments at every meeting.
What were those early meetings like? A real mix.
Sometimes you'd have incredibly important experiments,
like Robert Boyle demonstrating his vacuum pump.
Other times it was, you know, much more trivial
stuff. But the Spear was always hands -on, observational,
and about collective vetting of knowledge. And
their single greatest contribution to the future
of science? Has to be their journal, Philosophical
Transactions, which started in 1665. The first
scientific journal? The world's oldest and longest
running. And it established two principles that
are still the bedrock of science today. Scientific
priority, who gets the credit, and peer review.
It created the formal system for sharing and
validating new knowledge. And the French followed
suit soon after. The French Academy of Sciences
was founded in 1666, but it was a very different
beast. It wasn't a private club of gentleman
scholars like the Royal Society. It was a government
body. It was an organ of the state, founded by
the king's minister, Jean -Baptiste Colbert.
It had state funding, salaries for its members,
and was often focused on problems of national
importance, like mapmaking or improving navigation.
So let's turn from the method to the actual discovery,
starting with a big one, astronomy, the displacement
of Earth from the center of everything. It was
just a conceptual earthquake. For millennia,
the Earth was the stable, unmoving foundation
of reality. The idea that it was just another
planet hurtling through space was, well, deeply
unsettling. It completely destroyed that neat
division between the perfect heavens and the
imperfect Earth. It had to. If the Earth moves,
then it must be made of the same stuff as the
planets. And if the planets are like the Earth,
they must be changeable, imperfect. The whole
Aristotelian cosmos just crumbles. But it took
a while for Copernicus's idea to really catch
on. What was the big objection people raised?
The lack of observable stellar parallax. Can
you explain that? Sure. If the Earth is orbiting
the Sun, then our viewing position changes dramatically
over six months. So the nearest stars should
seem to shift their position slightly against
the background of more distant stars. Like when
you hold your thumb out and close one eye than
the other, your thumb seems to jump. That's the
perfect analogy. They looked for that shift,
and with the instruments they had, they couldn't
see it. So for decades, many people thought Copernicus'
system was just a useful mathematical trick,
not a description of physical reality. Then comes
Johannes Kepler, with access to the best data
in the world. Tycho Brahe's data. Incredibly
precise naked eye observations made over decades.
And Kepler, who is a mathematical genius, spends
years trying to make the data for Mars fit a
circular orbit. And it just won't work. It's
off by a tiny amount, but it's enough. So he
makes this incredible intellectual leap and tries
an ellipse. And it fits. Perfectly. So planets
move in ellipses, not circles. Which was a death
blow to the old cosmology. The heavens were not
perfect. Planets were just bodies moving according
to physical laws. His book, Astronomia Nova,
is one of the most important works of the whole
revolution. And then Galileo comes along and
provides the killer observational evidence with
his telescope. He weaponized it for astronomy.
Every single thing he saw through it was another
nail in the coffin of the Ptolemaic system. The
moons of Jupiter. Right. If Jupiter has moons,
then not everything orbits the Earth. The phases
of Venus. That was the big one. He saw that Venus
goes through a full set of phases, just like
our moon. That's only physically possible if
Venus orbits the sun, not the Earth. And the
mountains on the moon and spots on the sun. Exactly.
They proved that celestial bodies were not perfect,
unchanging, ethereal spheres. They were worlds,
just like ours. blemished and changeable. But
there is still that common sense objection. If
the earth is spinning and flying through space,
why don't we all just fly off? Why does a rock
drop from a tower land at its base? And Galileo
had a brilliant answer for that, a preliminary
theory of inertia. He argued that the rock, the
tower, and the person dropping it are all already
moving together with the earth. So the rock doesn't
lose that sideways motion just because you let
it go? It retains it. It's just adding a downward
motion to the horizontal motion it already had.
It's a revolutionary concept that dismantled
the last major argument against a moving Earth.
And Newton, with the Principia, delivers the
final synthesis. He unifies the whole thing.
His laws of motion and universal gravitation
show that the force that makes an apple fall
to the Earth is the very same force that keeps
the Moon in orbit around the Earth and the planets
in orbit around the Sun. One set of laws for
the entire universe. The end of the two realms.
The cosmos was a single unified machine governed
by universal mathematical principles. And with
that, the heliocentric model was no longer in
doubt. Following that idea of the machine, let's
shift from the cosmos to the body, to biology
and medicine, where the authority of Galen was
just as absolute as Aristotle's. For more than
a thousand years, if you were a physician in
Europe, the works of Galen were your Bible. But
Galen had a problem. He wasn't dissecting humans.
He was working in the Roman Empire, where human
dissection was forbidden. So his anatomy was
based largely on dissecting animals, pigs, Barbary
apes. In Vesalius, in 1543, changes that. He
breaks the taboo. He performs human dissections,
and his book, De Huani Corporis Fabrica, is filled
with incredibly detailed and accurate drawings
based on what he actually saw. And what he saw
often contradicted Galen. So he was promoting
an empirical, observational view of the body.
Exactly. The body as a physical structure in
three -dimensional space that had to be seen
and mapped, not just read about in an ancient
text. What were some of the specific errors he
corrected? Big one was in the heart. Galen believed
there were tiny pores in the septum, the wall
between the two main chambers, allowing blood
to seep from one side to the other. Based on
what he saw in pigs. Right. Vesalius looked at
human hearts and said no. The septum is solid.
There are no pores. Which raised a huge question
about how blood actually moved. He also gave
us the first good descriptions of all sorts of
bones and organs and the best anatomy of the
brain up to that point. So Vesalius gives us
the structure, then William Harvey gives us the
function. Harvey gives us physiology. His 1628
book, De Motu Cordis on the Motion of the Heart,
is a masterpiece of the new scientific method.
It combines careful experiment with elegant mathematical
deduction. How did he use math to attack the
old theory of blood? Well, the Galenic theory
was that the liver constantly made new blood
from the food we eat, and the body then consumed
it like fuel. Okay. So Harvey did a simple calculation.
He measured how much blood the heart's ventricles
could hold. He multiplied that by the number
of heartbeats in an hour, and the result was
just, well, absurd. What did he find? He found
that for the Galenic theory to be true, the liver
would have to produce something like 540 pounds
of blood every single day. An impossible amount.
The sheer math showed the old theory had to be
wrong. So what was his alternative? That the
blood circulates. It's a closed system. The heart
is a pump that drives the same blood around and
around the body. And he proved this with experiments.
Simple, elegant experiments. He would tie ligatures,
or tight bands, on people's arms. A very tight
band would cut off all flow, and the arm would
go cold and pale. But if he loosened it just
a little, enough to let arterial blood in but
block the veins from taking it back out, the
arm would swell up, it would get warm and red,
and the veins below the ligature would bulge
with tracked blood. It was undeniable proof of
a one -way circular flow. Beyond these two giants,
you see a lot of specialization starting to happen
in medicine. You do. A physician named Jean Fresnel
coins the term physiology to describe this new
study of bodily function. You have Pierre Fauchard
basically inventing modern dentistry and Ambroise
Perret revolutionizing surgery, especially on
the battlefield. Now let's move to chemistry,
which had to fight its way out of the shadow
of its mystical twin, alchemy. They were very
deeply entangled. I mean, hugely important figures
like Tycho Brahe and even Isaac Newton were serious
alchemists. And chemical philosophy, unlike mechanical
philosophy, often talked about the active powers
in matter, vital principles, spirits. But the
shift toward a more practical, less mystical
approach started in industry. It started with
mining and metallurgy. A 1556 book, De Raid Metallica
by Georges Agricola, was hugely important. It
was a practical manual describing in meticulous
detail the processes of mining and extracting
metals. It stripped away the mysticism. But the
figure who really defines the break, who is called
the first modern chemist, is Robert Boyle. Boyle
is the one who systematically applies the new
scientific method to chemistry. His book from
1661, The Skeptical Chemist, is a direct assault
on the old alchemical ideas. What was his main
argument? He argued from the mechanical philosophy.
Chemical reactions weren't caused by mystical
sympathies or active spirits. They were the result
of the physical collisions of particles in motion.
And he wanted chemistry to stand on its own two
feet. Yes. He pleaded for it to stop being just
a handmaiden. to medicine, or a search for the
philosopher's stone. He said it should be a science
in its own right, and that every single theory
had to be proven experimentally. And he backed
that up with one of the first great quantitative
laws in chemistry. Boyle's Law, from 1662. The
inverse relationship between the pressure and
volume of a gas. It's a simple mathematical equation.
P times V equals a constant. It proved that chemistry
could be just as mathematical and rigorous as
physics. Finally in this section, let's look
at the physical sciences, especially optics and
electricity. Optics made huge strides. Kepler,
again, founded moderate optics in 1604, figuring
out things like the inverse square law for light
intensity. And Wilbur Snellius discovers the
law of refraction. And then Newton comes in and
completely changes our understanding of color
itself. His experiments with prisms are just
legendary. He showed that a prism doesn't create
color. It separates or decomposes white light
into the spectrum of colors it already contains.
And a second prism could put them back together
into white light. Right, which led to his revolutionary
theory that color isn't a property of objects.
It's a property of light. Objects just reflect
or absorb certain colors that are already present
in the light hitting them. He laid this all out
in his book, Optics. And the practical side of
optics, the microscope, opened up a whole new
universe. While Galileo was looking up at the
stars, Anthony van Leeuwenhoek was looking down
at a drop of pond water. He built these incredibly
powerful single -lens microscopes and was the
first human to see bacteria, blood cells, all
sorts of microscopic life. He essentially founded
the field of microbiology. And what about electricity?
William Gilbert, the magnetism guy, shows up
here again. He's the founder of the electrical
science. In Tate -Maguette, he coined the term
electricus from the Greek word for amber, which
was the one substance the ancients knew had this
property. Static electricity. Exactly. And Gilbert
systematically tested hundreds of substances
and found that many others, sulfur, wax, glass,
also had this property when rubbed. He also made
the key discovery that moisture prevented it
from working. And Robert Boyle makes another
appearance here. Boyle proved that this electrical
attraction could work across a vacuum. That was
huge because it showed that the effect didn't
need air to be transmitted. It was some kind
of fundamental force. And you start to see the
invention of devices to study this new force.
Otto von Gehrig. who invented the vacuum pump,
also invented an early electrostatic generator.
And the word electricity itself enters the English
language thanks to Thomas Brown in 1646, long
before anyone really understood what it was.
It's clear that none of this would have been
possible without the tools, the machines of knowledge
that allowed for this new level of precision.
They were completely integral. You can't have
a mathematical science of the heavens if the
calculations take a lifetime to perform by hand.
Which is why the invention of logarithms was
such a big deal. A computational miracle. John
Napier's logarithms turned brutally complex multiplication
and division problems into simple addition and
subtraction. It was an essential tool for people
like Kepler. And we also see the very first steps
toward what we would call computers. The lineage
is really clear. It starts with analog devices
like the slide rule, invented by William Autred
in 1622. And then the first mechanical adding
machines. Blaise Pascal builds his Pascaline
in 1642. Then Gottfried Leibniz, the co -inventor
of calculus, goes even further and designs a
machine that can multiply and divide. And Leibniz
gives us the theoretical foundation for all digital
computers. He refines the binary number system,
the ones and zeros. It's incredible to think
that at the same time they're mapping the cosmos,
they're also mapping the fundamental logic of
computation. The need for accuracy was driving
all of this innovation. And beyond calculation,
they needed new ways to measure the invisible
world around them, like air pressure. Which brings
us to Evangelista Torricelli and the invention
of the mercury barometer in 1643. And this came
from a very practical problem. Trying to get
water out of mines. Exactly. Suction pumps could
only lift water about 30 feet, and no one knew
why. Torricelli realized it was because the weight
of the atmosphere was pushing the water up the
pipe. And the barometer was his way of proving
it. He used mercury. which is much denser than
water, in a sealed glass tube. The column of
mercury only rose to a height that perfectly
balanced the weight of the atmosphere, leaving
a vacuum at the top of the tube, the first quantitative
measurement of air pressure. And that vacuum
itself became a huge subject of study. Which
required the vacuum pump, invented by Otto von
Gehrig in 1st 654. And he used it for his most
famous public demonstration. The Magdeburg Hemispheres.
One of the great theatrical moments in the history
of science. He took two large copper hemispheres,
fitted them together to make a sphere, and pumped
the air out. And the air pressure on the outside
held them together. Held them together so tightly
that two teams of eight horses couldn't pull
them apart. A dramatic, unforgettable proof of
the power of the atmosphere and the reality of
the vacuum. In observation, we talked about the
telescope, but there was a big split between
the two main types. Refracting telescopes, which
use lenses like Galileo's, had a fundamental
flaw called chromatic aberration. The color fringing.
Right. A lens bends different colors of light
at slightly different angles, so you can never
get a perfectly sharp image. Newton argued this
made refractors fundamentally limited. So his
solution was to use mirrors instead of lenses.
Because a mirror reflects all colors of light
at the exact same angle. He built the first functional
reflecting telescope in 1668, a design that would
become the standard for all large astronomical
telescopes in the future. And all this pure science
starts to lead directly to the machines that
will power the next great shift in history, the
Industrial Revolution. The connection becomes
undeniable. The physicist Dennis Papin invents
the steam digester, basically a pressure cooker,
which is the direct forerunner of the steam engine.
Which leads to the first practical engines for
industry. Thomas Savory patents the first working
steam engine in 1698 for pumping water out of
mines. Then Thomas Newcomen perfects a much more
efficient design. Newcomen's engine really is
the machine that kicks off the Industrial Revolution.
And you need better materials to build all these
new machines. Which is where Abraham Darby comes
in. He figures out how to use coke, which is
derived from coal. instead of charcoal, to fuel
his blast furnaces. This allows for the mass
production of high -quality cheap iron, the essential
raw material of the Industrial Age. Before we
move on, it's worth noting that the scientific
instruments that have survived from this period
can be a bit misleading. That's a really important
point of historical context. The instruments
you see in museums are often these beautiful,
ornate objects made of brass and gold. Commissioned
by wealthy patrons. Exactly. They were status
symbols as much as scientific tools. Yeah. The
actual workhorse instruments, the ones that were
used every day in the lab, were probably much
simpler, got worn out, broken and thrown away.
They weren't considered collection pieces. So
what we see is a biased sample. A very biased
sample. But the growing demand for accurate instruments
for navigation, surveying and warfare is what
created the market and the manufacturing skills
that the Industrial Revolution would build upon.
We've called this a revolution all the way through,
but that idea of a sudden radical break isn't
universally accepted by historians. We should
dig into some of those criticisms. Absolutely.
The first major challenge is the continuity thesis.
This argument, championed by people like Pierre
Duhem, says there was no radical break at all,
that the idea of a dark age followed by a sudden
revolution is a myth. So where do they see the
new ideas coming from? They argue that intellectual
development flowed more or less continuously
from the Middle Ages. They point to the 12th
century Renaissance, when all these Greek and
Arabic texts were translated, and say that many
of the revolutionary ideas were already being
debated and developed by medieval scholars. The
change was more of the gradual acceleration.
Okay, so that's one view. It was gradual. What's
another perspective? The reassertion thesis,
or the Renaissance thesis. This view agrees there
was a break with the immediate past, with Aristotle.
But it argues the revolution wasn't the creation
of new knowledge, but the relearning of older
classical ideas that Aristotle had eclipsed.
So again, it's about reviving lost knowledge.
Exactly. They'd point out that Copernicus was
reviving the Pythagorean worldview, that Archimedes
already had a sophisticated mathematical physics.
In this view, the revolution was just an extension
of the Renaissance recovery of classical texts.
Then you have a much more recent argument that
challenges the whole Eurocentric. frame of the
story. The multicultural influence argument put
forward by scholars like Arambala. And his argument
is that the key innovations, mathematical realism,
the mechanical philosophy, heliocentrism, were
not internally generated in Europe. They were
the result of Europe absorbing and transforming
ideas from other cultures. What kind of influences
are we talking about? All sorts. He points to
the influence of the Islamic scientist Al -Hazen's
work on optics, which was crucial for Kepler.
The influence of Chinese mechanical devices,
like clocks, on the idea of the universe as a
machine. The Hindu -Arabic numeral system itself,
which made the new math possible. So Europe was
more of a crucible where all these different
ideas were melted down and reformed into something
new. That's the core of it. Bala acknowledges
that the final accomplishment, the creation of
this new unified system, belonged to the Europeans
like Copernicus and Newton. But he argues the
raw materials were multicultural. Finally, there's
the criticism about who gets left out of this
story, specifically women. It's a vital modern
perspective. The new institutions of science,
the Royal Society, the universities, were almost
exclusively male domains. Women were structurally
excluded from formal participation. But that
doesn't mean they weren't contributing in other
ways. Of course not. We know women were making
advances in areas like herbal medicine, pharmacy,
domestic chemistry. But because they weren't
part of the formal record -keeping institutions,
their contributions are largely available to
history. It's ironic that the very system being
created, with its focus on peer review and formal
publication, is what later allowed women scientists
to finally get their due. It is. The foundations
were laid for a more objective system, but the
doors to that system were closed to half the
population at the time. So, to pull this all
together, we called this a seismic shift. And
it's clear why. It wasn't just about the big
discoveries, as world -changing as they were.
No. The final takeaway has to be about the method.
The realization that the natural world must be
investigated mechanistically, mathematically,
and through rigorous, repeatable experiments.
And that this whole process needed to be institutionalized,
made into a system. That reliance on external
observation, on data, is the true legacy. As
one historian put it, it was the transition from
implicit trust in the internal powers of man's
mind to a professed dependence upon external
observation. That dependence on observation is
the bedrock of our world. And it was formalized
through those 17th century structures like the
Royal Society's journal, which gave us priority
and peer review. A system that was born in the
age of the printing press and gentlemen's clubs.
And today? That system is global, digital, and
under unbelievable pressure from the speed of
information. Which brings us to our final provocative
thought for you to take away from this. If you
were starting a new global scientific institution
today, right now. Knowing that the system we
have was designed for a world of paper letters
and slow communication. How would you redesign
the process of publishing and credentialing science
to guarantee integrity, but also to work at the
speed and scale of the 21st century? Would you
build on those 17th century foundations? Or does
our digital age require a new revolution, a fundamental
break of its own? Something to think about.