I started this course by saying that people
have made knowledge about the natural world,
pretty much forever.
They’ve done this by carefully observing
the world and then devising tests to find
out if their ideas are true.
Today, we refer to a specific series of steps—coming
up with a hypothesis, testing it, and drawing
conclusions—as the scientific method.
But, historically speaking, there is no one
scientific method.
There’s more than one way to make knowledge.
Still, if you look at some of the great minds
who helped shape today’s concept of the
scientific method, a set of basic principles
starts to emerge.
Like rationality.
Experimentation.
And ruthless self-examination.
For these ideas and a lot of other stuff, we have to
thank three of the natural philosophers who
pioneered this abstract “scientific method”:
Galileo, Bacon, and Descartes.
[INTRO MUSIC PLAYS}
Galileo, Bacon, and Descartes are each so
fascinating that they could each have their
own episode.
But one reason to talk about them together
is that they lived at roughly the same time.
A lot changed in European natural philosophy
between the mid-1500s and the mid-1600s, when
Newton started dropping his hits.
We’ll get there later!
But first, Dr. Galileo Galilei was born in
Pisa in 1564.
He considered becoming a priest, studied art,
attended school for medicine, but then attended
a lecture on geometry, and went on to study
math in secret, because his dad wanted him
to focus on medicine.
Much to his father’s chagrin, I’m sure,
Galileo became a professor of a bunch of math-related
stuff at University of Pisa, a lowly, poorly
paid position.
In 1593, Galileo took a job as a ballistics
consultant at the Arsenal of Venice, which
is a heck of a title to have on your C.V.
Then, starting in 1609, he built and refined
telescopes, which eventually made him famous.
The very first telescope was invented by Dutch
spectacle-maker Hans Lippershey in Holland
in 1608.
But Galileo’s versions were much better.
And telescopes are a good example of how scientific
instruments change the nature of scientific
practice.
We often design experiments around how we
can use our instruments—in the case of astronomy,
around what we can see through a telescope.
With his new telescopic success, Galileo quit
his job at Pisa for a much better one at Padua,
and he also took on the role of Chief Mathematician
and Philosopher of Florence.
I love this guy's resume!!!
As he continued to research the night sky,
Galileo became convinced that Copernicus was
right: the earth is not the center of the
universe.
He also looked into Kepler’s ideas but wasn’t
convinced by them.
By 1611, Galileo’s name had been brought
up by the Inquisition.
And, of course, nobody expects that.
But it seems that his vocal support of Copernicanism
was creating some friction in the Florentine
court.
Among many others, the Grand Duchess Christina,
who was basically one of his patrons, said
she took issue with the idea of heliocentrism.
So in 1615, he wrote to a letter to explaining
that the Bible and nature did not disagree:
One was God’s word to the masses—a story
about how to behave and why.
The other was God’s work—the physical
reality that He created.
So science, he said, was simply the uncovering
of God’s work.
Galileo was a man of faith!
Unfortunately for him, Church officials didn’t
like this explanation.
In 1616, the Church added Copernicus’ text,
De rev, to its official list of banned books.
The Inquisitors deemed heliocentrism “foolish
and absurd in philosophy.”
This was bad news for Galileo: he was told
not to uphold or defend Copernicanism.
(But he may have been able to teach a heliocentric
astronomy as a thought experiment.
Historians aren’t sure.)
But Galileo wasn’t having any of it.
In 1623, Galileo published a pamphlet called
the Assayer that basically said scientists
should be free to do their work.
Pope Urban VIII, Galileo’s personal friend,
was a fan.
He said that God could move the heavens in
numberless ways, so the ultimate source of
truth would always be faith.
So sure, Galileo, you want to spend your nights
staring at tiny dots of light?
Knock yourself out.
Urban even renamed Galileo’s next book,
Dialogue on the the Two Chief World Systems
of 1632.
All Urban asked was for his friend to treat
different astronomical systems fairly.
But…
Galileo picked a fight.
The Dialogue made a clear argument for Copernicanism,
comparing it point by point with the Aristotelian–Ptolemaic
system.
He brought new data to the battle: he described
the phases of Venus, which appears to grow
larger and smaller like earth’s moon.
This phasing did not fit with a geocentric
model.
An even stronger argument came from the tides,
whose movements seemed to prove that the earth
moves.
And the pope was not happy.
Urban felt that Galileo had not heard his
warning.
All copies of the Dialogue were recalled.
And in 1632, Galileo was called to Rome to
speak to the Inquisition.
His trial got under way in 1633, and in time,
he was placed under house arrest for the rest
of his life.
Amazingly, Galileo didn’t give up.
Humiliated, under arrest, he kept sciencing.
Beyond his contributions to astronomy, physics,
and the scientific method, Galileo is a rockstar
thanks to his fearlessness.
Galileo’s last text was also perhaps his
most relevant to the idea of methods in science:
His Two New Sciences of 1638 was a mathematical
treatise about how bodies fall through the
air, and how wooden beams break.
It was also a record of the process by which
he discovered these physical laws.
He called for specific tests that would let
experimenters confirm his laws with their
own senses.
This, in his words, was the mark of a “true
scientist”: independent confirmation.
This is an awesome norm to try to live up
to!
So, we shouldn’t be surprised that a lifelong
nerd like Galileo would have played a critical
role in developing better methods of doing
science.
But Francis Bacon, born in London in 1561,
is more of a historical surprise.
For one, he was cast out of public office
for taking bribes.
Two, some people for some reason think he
was Shakespeare.
And I mean, if you’ve ever read these two
writers… there’s a clear difference.
And most of Bacon’s impact on science was
posthumous.
We can basically boil it to down to a new
approach to science, which was practical,
instrumental, and supported by the state.
Bacon wanted to create a whole replacement
system of natural philosophy—that meant
philosophy, mathematics, physics, biology,
all wrapped up together.
He rejected the Aristotelian way of doing
science—arguing rationally using logic.
Instead, he believed that natural philosophers
should help improve the wellbeing of humanity
through technological advances.
Bacon expressed this within a Christian framework,
casting Aristotle’s philosophy as a dereliction
of the Christian duty of charity toward others.
Improving wellbeing meant understanding and
controlling the chaos of the natural.
Bacon described nature as female and passive,
and humanity as male and active.
So, science was supposed to be a masculine
activity: it allowed humans to exploit nature.
Now, this metaphor has not aged well at all,
and not just because it was sexist and horrible.
We also now have plenty of examples of all
the ways that humans simply can’t control
nature.
And yet this metaphor is, sadly, still very
much alive.
So.
What did Bacon’s new system of natural philosophy
look like up close?
Help us out, ThoughtBubble:
For Bacon, control over nature meant deriving
useful arts—or technē—like gunpowder,
silk, and the printing press, from basic knowledge.
And how were Baconians supposed to make useful
knowledge?
They needed first-hand experiences.
This meant testing answers to important questions,
without relying on the words of long-dead
Greek and Arabic philosophers.
For Bacon, science also required central planning
and state support.
Natural philosophy should not be the domain
of a few random nobles, he thought.
It should be a program, or system, that worked
for the public good.
He outlined a vision of a utopian science
bureaucracy in his book called New Atlantis,
published in 1626.
Bacon proposed creating a hub for intellectual
work, a kind of super-university called Salomon’s
House.
Here, the personnel—all male, of course—would
be strictly segregated into specific roles.
Some would travel the world to gather facts.
Others would conduct experiments to generate
new facts.
Yet others would extract potential facts from
books—but these proto-facts would have to
be tested experimentally.
Further up the hierarchy, others would analyze
all of the different natural facts and experimental
outcomes and direct the next round of research.
And at the very top were the Interpreters
of Nature—three men who would take all facts
and use them to produce axioms.
Working along with them were “dowry men”
who drew conclusions from these axioms to
yield specific practical benefits.
That, in a nutshell, is the scientific world
according to Bacon.
Thanks Thought Bubble, Now, another thinker who advocated for a practical
science was René Descartes.
Born in central France in 1596, Descartes
lived mostly in the Netherlands.
He’s known as a founding figure in mathematics
and modern philosophy.
So, that's not bad.
In math, he’s known as the dude who bridged
geometry and algebra.
We call the numbered X–Y axes the plane
of “Cartesian” coordinates.
You can map a lot of math with this system.
Now, Descartes knew what had happened to Galileo,
and his publishers in France didn’t want
to wind up on trial, too.
So Descartes stopped publication of his own
Copernican book, Le monde or The World, in
1633.
But he did come up with a whole new cosmology,
based on Copernicus, that featured a chaotic,
rapidly moving ætherial fluid in which the
planets and stars were suspended—instead
of perfect crystalline spheres.
His Discourse on Method, published in 1637,
was his major contribution to the history
of making knowledge.
But, more than Galileo—a practicing experimentalist—or
Bacon—a statesman thinking about the practical
uses of natural philosophy—Descartes was
a pure philosopher.
He started at the very beginning with an abstract
question: how we know what we know?
This is question at the heart of the philosophical
discipline of epistemology, which Descartes
redefined.
Philosophers today are still debating some
of the questions Descartes raised about the
origins of knowledge.
Descartes wanted to replace Aristotle as the
king of philosophy.
And Descartes’s attack on Aristotle boiled
down to two arguments: one, knowledge obtained
through the senses lacks absolute certainty,
because the senses often deceive us.
And two, human reason can also be deceived!
Logical conclusions from false premises will
lead you to the wrong answers.
So Descartes was like, welp, time to formulate a whole
new philosophy to address these points.
Ultimately, to be certain of the truth, Descartes
could only count on one thing: his mind.
So he described the world reductionistically,
meaning using math to represent physical phenomena.
Only math, which is either right or wrong,
could found a total system of natural philosophy.
For Descartes, the universe is composed only
of things that math can describe.
He thought that philosophers should be able
to provide causal explanations for all observed
phenomena, showing the or the mechanical
principles behind the things that happen in
the universe.
And the tactic Descartes used for checking
the validity of your own knowledge is famous
and still useful today: systematic doubting.
When in doubt, doubt yourself!
This pairs nicely with what Bacon argued:
don’t trust old books; check!
When you add Galileo’s focus on independent,
rational comparison of theories about natural
phenomena to Bacon’s focus on experiment
and social norms promoting scientific research,
and then Descartes’s reminder to always
ask yourself how sure you are that you know
stuff, you get a kind of method or system.
Was it thought of as a single philosophy at
the time?
Sort of.
Some of the most important members of the
early Royal Society, where we’ll head in
a couple of episodes, pointed explicitly to
Bacon as an inspiration.
But this story isn’t all all about better
descriptions of the Solar System.
It’s also about winning wars and conquering
new territory.
Stay tuned.
Next time—we’ll look at how the “new
science” affected the healing arts and beliefs
about the human form… and, yes, there will
be dissections.
A lot of dissections!
Crash Course History of Science is filmed
in the Dr. Cheryl C. Kinney studio in Missoula,
Montana and it’s made with the help of all
this nice people and our animation team is
Thought Cafe.
Crash Course is a Complexly production.
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