Welcome back to the Deep Dive. We're so glad
you're here with us. It's great to be back. Today
we are looking at a figure who, um... Honestly,
he sort of defies the usual boxes we like to
put historical figures in. He really does. You
know, you usually have your science guys over
here, your Newtons, your Galileos, your Einsteins.
And then in a completely different building,
sometimes on a different planet, you have your
philosophers, your theologians. Yeah, your Krippegards,
your Augustans. Exactly. And they don't usually
talk to each other. They operate in different
worlds. Well, Stephen Jay Gould had that phrase,
non -overlapping magisteria. That's how it's
supposed to work. But today's subject, he didn't
just overlap them. He smashed them together.
We are talking about Blaise Pascal. Blaise Pascal.
And the sheer scope of his life is just staggering
when you think about it. A man who lived only
39 years. I mean, that's the first thing that
hits you. Born in 1623, gone by 1662. A very
short window. And in that brief window, he managed
to live what feels like three or four completely
distinct, brilliant lives. He invents the mechanical
calculator when he's basically still a teenager.
To help his dad with his taxes, no less? Right.
Then he lays the groundwork for probability theory.
Yeah. All because a gambler friend asked him
a question about a game. A very practical problem.
And he revolutionizes physics. By proving that
the atmosphere, the air around us, actually has
weight. Yeah. And then, after all that, he just
pivots. Yeah. He abandons science to become one
of the most profound, most challenging religious
writers in the entire Western canon. It is a
dizzying resume. I mean, it really is. And the
thing that makes Pascal so compelling, so fascinating
to dive into, is that he isn't just a jack of
all trades. He was a master of all of them. He
didn't just dabble. When he decided to do math,
he fundamentally changed mathematics. When he
turned to physics, he broke a 2 ,000 -year -old
Aristotelian consensus. And when he finally turned
his mind to God, he wrote this collection of
fragments, the Pensées, that philosophers and
theologians are still fiercely arguing about
400 years later. So the mission for this deep
dive then is to try and figure out how all those
pieces fit together. Because on the surface,
the person who invents a calculating machine
seems like a completely different person from
the guy who secretly sows a prayer into the lining
of his coat. It seems like a contradiction. It
does. But I have a feeling you're going to tell
me they're actually the same person driven by
the same thing. They absolutely are. I think
the common thread, the engine driving him through
all these different fields was this relentless,
almost. almost desperate pursuit of certainty,
of truth. Whether he was looking for truth in
the precise meshing of gears in a machine, or
in the empty space of a glass tube, or in the
silent contemplation of a monastery, he was applying
the same rigorous, uncompromising, analytical
intellect. He just wanted to know what was real.
Let's start at the beginning then, because the
origin story here feels absolutely vital to understanding
the man. Blaise Pascal. Born in Clermont -Ferrand,
France. June 19, 1623. His mother passes away
when he's just a toddler, only three years old.
So he's raised almost entirely by his father,
Etienne Pascal. And Etienne is a fascinating,
crucial character in his own right. He wasn't
just some bureaucrat. He was a tax collector,
yes. But he was also a member of the Noblesse
de Robe, which was the administrative nobility.
So an educated man. A powerful man. Very. And
an amateur mathematician himself. He was very
well connected in the intellectual circles of
Paris at the time. When Blaise was about eight
years old, Etienne actually moves the family,
that's Blaise and his two sisters, Gilbert and
Jacqueline, to Paris. And he makes this really
interesting decision to homeschool them, which,
I mean, in the 17th century, that's not exactly
the norm. Not at all. But Etienne had a very
specific, very rigid curriculum in mind. And
the most famous part of that curriculum was what
it was missing, mathematics. He had this idea,
this pedagogical theory, that a child's mind
should be trained first on languages and the
humanities, Latin, Greek. He thought mathematics
was too compelling, too absorbing. Maybe even
too taxing for a young mind. He thought it would
be a distractor. Total distraction. So he literally
banned geometry from the house. He hid the textbooks.
He told Blaze flat out, you are not to think
about mathematics until you are at least 15.
Which, I mean, if you know anything about raising
a curious child, that is the single worst tactic
you could possibly employ. That's a colossal
tactical error. You tell a brilliant kid that
something is forbidden. It becomes the only thing
they want. The most interesting thing in the
world. Precisely. It became the forbidden fruit.
So Blaze starts asking questions. What is geometry?
What does it even do? And his father gives him
this very vague general answer. Something like,
oh, it's the study of how to make precise figures
and find the relationships between their parts.
And that was all he needed. That was enough.
The fuse was lit. And this leads directly to
what might be the most famous story about Pascal's
childhood. The kitchen floor incident. Right.
He's 12 years old at this point. About 12, yes.
And Etienne comes home one day to find his son
on the floor with a piece of charcoal drying
on the tiles. Just doodling, he probably thought.
At first, maybe. But he watches for a bit. And
he sees Blaise's drawing shapes, circles, triangles,
lines. But here's the thing. Because no one had
ever taught him the official words, he was making
up his own language for it. Oh, that's incredible.
He called a circle around. He called a line a
bar. He was building his own private lexicon
for geometry. So he's not just drawing. He's
doing so much more. Etienne realizes that Blaise
isn't just making pictures. He's constructing
proofs. He is, from first principles, working
his way through Euclidean geometry. Without a
textbook. Without a teacher. Completely on his
own, by the time his father found him, he had
allegedly, and this is according to his sister
Gilbert's account, he had independently rediscovered
and proven the first 32 propositions of Euclid's
elements. Okay, let's just pause on that for
a second. The 32nd proposition of Euclid is the
one that says the sum of the angles in a triangle
equals two right angles. Yes. 180 degrees. Yes.
He derived that from scratch using charcoal on
a tile floor. At 12 years old. That is the story
that has come down to us. Now, you know, modern
historians might debate whether he reconstructed
the entire sequence perfectly or if he was just
grasping the core logic of it. But either way,
the intellectual achievement is just, it's staggering.
It's off the charts. He deduced the axioms of
geometry alone in a room. And when Etienne realized
what was happening, that his son had effectively
reinvented 2000 years of Greek mathematics in
their living room, the story goes. That he wept.
He must have realized he couldn't stop it. He
knew. He gave up. He went and got Blaze a copy
of Euclid's Elements, and Blaze, of course, just
devoured it in a matter of days. And that just
opened the floodgates. Because it wasn't long
after that, I mean, he's still a teenager, that
he's not just learning math anymore. He's contributing
to it. At 16, he writes the essay on conics.
On conic sections. Which is a short but incredibly
dense treatise on conic sections. You know, ellipses,
parabolas, hyperbolas, all the shapes you get
by slicing through a cone. And inside this essay,
he presents something new, what we now call Pascal's
theorem. Or the mystic hexagram, which is a much
better name. It is a great name. Explain that
to us. What is the mystic hexagram? Okay, so
it's a foundational concept in a field called
projective geometry. Imagine you have any conic
section, let's just say an oval to make it easy.
Now you draw a hexagon inside it so that all
six of its corners or vertices are touching the
edge of the oval. Hexagon can be all skewed and
irregular, right? Totally irregular. It doesn't
matter. Now take the opposite sides of that hexagon
and extend them out like lines until they cross
each other. You'll get three intersection points.
Pascal proved that those three points will always
lie on a single straight line. No matter how
you draw the hexagon. No matter how you draw
it, it feels like magic when you see it drawn
out. It's this hidden order. And it's important
to remember, this was cutting edge stuff. This
wasn't just solving odd problems. This was creating
new mathematics. He sent his paper to Father
Marine Mersenne in Paris. Who was like the central
node of the European scientific internet at the
time. He was the guy. He connected everyone.
And Mersenne, of course, shows it to the biggest
name in the game. Rene Descartes. The I think,
therefore I am guy. The philosophical heavyweight.
And you'd think he'd be blown away by this, but...
He wasn't. He was skeptical. In fact, he was
worse than skeptical. He was dismissive. When
Mersenne showed him the essay, Descartes' first
reaction was, I do not believe a 16 -year -old
wrote this. He thought the father wrote it. He
assumed it was Etienne, the father, trying to
pass off his own work to build up the family
name. He just couldn't accept that this level
of mature, abstract reasoning could come from
a boy. That's sort of the ultimate backhanded
compliment, isn't it? This is too good to be
yours. It really is. And even after he was finally
convinced that, yes, the kid actually wrote it,
Descartes was still sniffy about it. He said
something along the lines of, well, I can see
how a boy might stumble onto this one little
proof, but he won't go much further with it.
Wow. It just shows you, I think, the tension
between the established, rigid, Cartesian way
of thinking and this intuitive, almost frightening
brilliance of Pascal. So by 16, he's already
a mathematical prodigy. He's gotten the attention
and the scorn of the most famous philosopher
in Europe. But then, real life... sort of intrudes.
His father, Etienne, gets a new government post.
Right. This is a crucial shift in the story.
Etienne had briefly fallen out of favor with
the powerful Cardinal Richelieu, but he gets
reinstated and is sent to Rouen in Normandy to
be the king's tax commissioner. And Rouen at
this time was a mess. A total mess. There had
been tax revolts. The city was in chaos. And
Etienne's job was to go through years of disorganized
records and figure out who owed what. He had
to assess and collect taxes from thousands of
people. And the sheer volume... of the arithmetic
was, well, was crushing. You have to picture
the scene, right? Night after night, the father
is just hunched over a desk, buried in ledgers,
surrounded by flickering candlelight, doing endless
columns of addition and subtraction by hand.
And Blaze, who's now about 19, sees his father
just suffering under this mountain of labor,
and he decides he's going to help. But he doesn't
just offer to, you know, double -check the swims.
No. He thinks, I can build a machine to do this
for him. I will mechanize this mental drudgery.
This is the birth of the Pascaline, the mechanical
calculator. And I think we often just gloss over
this. We say he built a calculator, but we really
need to understand what an engineering nightmare
this must have been in the 1640s. It was a nightmare.
Because this isn't a simple machine that just
adds one plus one. Right, because of the money
system. Exactly. France wasn't using a nice,
clean decimal system. They were using livre,
sol, and denier. Walk us through how that works.
It's confusing. Okay, so livre was the main unit,
sort of like a dollar or a pound. But there were
20 sols in a single livre. And then there were
12 deniers and a single sole. So it's base 12,
then base 20, then base 10 for the rest. Exactly.
So if you're building a machine to add this up,
you can't just have every gear have 10 teeth.
You need a gear with 12 teeth for the deniers,
which then has to turn a gear with 20 teeth for
the soles, which then has to turn the lever gears.
And they all have to work in perfect sync. In
sync. And the real killer, the problem that had
stumped everyone before, was the carry mechanism.
You mean like when you're adding and you get
to nine? You ride a zero and carry the one? Precisely.
On the machine, if your sole's wheel is at 19
and you add one more sole, that wheel has to
click over to zero and it has to give a push
to the next wheel, the lever wheel, to move it
forward by one. So it's a chain reaction. It
is. And if you have a number like 9 ,999 lever
and you add one, you have to carry across four
or five heavy brass gears all at once. The cumulative
friction, the force required, would jam any simple
machine. would just lock up. It's like a domino
effect of friction and force. So how did he solve
it? He invented a mechanism of pure genius. It's
called the sautoir. It's basically a little gravity
-assisted pawl, like a tiny weighted lever. As
you turn a number wheel, it slowly lifts this
little weight. Okay. Then, right when the wheel
clicks past its final number, say, from 11 to
0 on the denier's wheel, that little weighted
lever drops. And the energy from that falling
weight provides the kick, the little burst of
force needed to turn the next wheel one notch.
So he's isolating the force. He's isol - he's
using gravity as a tiny temporary battery for
each individual carry. It meant the user felt
the same easy resistance whether they were adding
one to one or one to 9 ,999. That is just so
clever. But it must have been incredibly difficult
to actually build. Oh, it was a torment. The
metalworking skills in the 1640s, they just weren't
up to the kind of precision that Pascal needed.
He went through more than 50 prototypes. He had
to personally stand over the blacksmiths and
the clockmakers because they kept getting the
tolerances wrong. He spends three years on this,
right? He finally gets a working model in 1645.
He even gets a royal patent from the king. This
should have been a world -changing invention.
And technologically, it was. It was the first
truly functional calculator that could be operated
by a non -expert. It worked. But as a business.
A disaster. A complete and total disaster. A
commercial failure. Why? I don't get that. If
it saves so much time and effort, why didn't
every accountant and merchant in France buy one?
Two main reasons. First, the cost. It was outrageously,
exorbitantly expensive. The fine materials, the
precision labor. A single Pascaline cost more
than most skilled craftsmen earned in a lifetime.
So it becomes a status symbol. Exactly. It became
a toy for the aristocracy. If you were a wealthy
duke, you'd have a Pascaline on your desk to
show off his cleverness to your friends, but
you probably weren't using it to actually do
your estate accounts. It's the original expensive
tech gadget that nobody really needed, but everyone
wanted on their desk. It absolutely is. And there
was also, interestingly, some resistance from
the clerks and accountants themselves, a bit
of fear of job replacement. They worried this
machine would make them obsolete. The first fears
of automation. You could say that. In the end,
only about 20 finished machines were ever built
over a decade. But the legacy, of course, is
massive. Pascal proved that mental labor calculation
could be mechanized. He's really one of the grandfathers
of computer hardware. So he's conquered theoretical
math. He's basically invented hardware engineering.
Now let's pivot to the next big phase of his
life. We're in the late 1640s now. The family
has moved back to Paris. And Pascal gets fascinated
by physics. Specifically, the physics of nothing.
The physics of the void. This was one of the
hottest, most contentious scientific debates
of the entire 17th century. The nature of the
vacuum. And the prevailing wisdom going all the
way back to Aristotle. was horror vacuuming.
Nature abhors a vacuum. We hear that phrase a
lot, but what did that actually mean to them?
Was it just a poetic way of speaking? No, no,
they took it absolutely literally. Aristotle
and his followers, which included Descartes,
by the way, believe that space is a plenum. It
is completely full. There are no empty gaps.
If you move an object, air, or some other invisible
matter, an ether instantly, magically rushes
in to fill the space. So for them, A true void,
true nothingness was physically impossible. And
maybe even theologically impossible, because
if God is omnipresent, how can there be a place
where nothing, not even God, exists? So asserting
that nothing could exist was a deeply controversial,
even dangerous idea. But then Pascal hears about
these strange experiments being done down in
Italy. by Evangelista Torricelli, who was a student
of Galileo. Torricelli had taken a long glass
tube, sealed at one end, filled it completely
with mercury, plugged the open end with his finger,
and then flipped it upside down into a bowl of
mercury. And when he took his finger away? The
column of mercury in the tube fell, but it didn't
fall all the way. It stopped at a certain height,
about 30 inches or 760 millimeters. Leaving a
gap at the top of the tube in the sealed end.
Exactly, the Torricellian space. And the big
question was... What is in that space? The Aristotelians
scrambled for explanations. They said it must
be filled with mercury vapor or a pocket of that
invisible ether. Pascal heard about this and
had a simpler idea. He said, no, it's empty.
It's a vacuum. It's nothing. And being Pascal,
he didn't just write a polite paper about it.
He designed a show. He loved these big, dramatic
public demonstrations. He was a bit of a showman.
A total showman. He published a paper called
New Experiments with the Vacuum in 1647. And
he repeated Torricelli's experiment, but he did
these wild variations. He used water and red
wine instead of mercury. I love the detail about
the wine. Right. He used different liquids to
prove it was about density and weight. And because
water and wine are much lighter than mercury,
The column stood much, much higher. He had to
use glass tubes that were 40 feet long and strap
them to the masts of ships in the middle of a
courtyard in Rouen. It was a spectacle. But the
crucial part was his explanation for why the
liquid stood up in the tube at all. Yes. The
Old Guard, the Aristotelians, said that the vacuum
at the top was actively pulling the liquid up,
a kind of suction force. Pascal suspected the
exact opposite. He thought it was the immense
weight of the ocean of air above us pushing down
on the surface of the liquid in the bowl that
was forcing it up into the tube. Atmospheric
pressure, the idea that we are all living at
the bottom of a deep sea of air. That's the concept.
And to prove that, he came up with a brilliant
idea for an experiment. He realized that if air
has weight, then there must be less air and therefore
less pressure at the top of a mountain than there
is at the bottom. This is the PD dome experiment.
This is the definitive Mike drop moment of 17th
century physics. Pascal reasoned it all out,
but there was a problem. He was always sickly.
He suffered from debilitating stomach pains,
terrible migraines his whole life. There was
no way he could hike up a mountain himself. So
he outsources the work. He does. He writes a
letter to his brother -in -law, Florent Perrier,
who conveniently lived near the Prix du Dome,
which is a large volcanic mountain in central
France. I can just imagine the letter. Dearest
Florent... Hope you were well. Would you mind
doing me a small favor in climbing a nearly 5
,000 -foot mountain while carrying a very delicate
glass tube full of toxic mercury? Thanks, Blaze.
That's pretty much it. And to his credit, Florin
did it. On September 19, 1648, Perrier assembled
a team of local dignitaries, priests, officials,
doctors to act as official witnesses. He wanted
to make sure it was all documented properly.
Oh, yes. This was science as a legal proceeding.
So first, they set up the barometer in the garden
of the Minim Fathers Monastery at the base of
the mountain. They measured the height of the
mercury column. It stood at 26 French inches
and three and a half lines. And then they start
climbing. Then Perrier and his team start the
3 ,000 -foot ascent to the summit. When they
get to the top, in the wind, they set up the
apparatus again. And the result? The mercury
had dropped. It was significantly lower. It was
now only 23 inches in two lines, a difference
of more than three inches. Which is a huge difference.
It's massive. And to be thorough, they measured
it at several points on the way back down, and
the mercury column rose steadily and predictably
as they descended, returning to its original
height back in the garden. It was irrefutable.
The weight of the air was the cause. The suction
of the vacuum was a myth. It was dead. And Pascal,
to confirm it, replicated the experiment himself
on a smaller scale at the top of a church bell
tower in Paris. This changed everything. It wasn't
just about how barometers work. It fundamentally
changed our understanding of the world we live
in. We aren't in some magical full plenum. We
are on a rock wrapped in a finite blanket of
gas that obeys physical laws. And this seems
to have cemented his idea of what science should
be. He established a really rigid standard. He
did. In a famous letter to a critic, a Jesuit
named Etienne Noel, Pascal basically laid out
the modern principle of falsifiability 100 years
before Karl Popper. He said, in effect, your
theory can explain 99 phenomena perfectly, but
if one single repeatable fact contradicts it,
your theory is false, period. It doesn't matter
what Aristotle said. It doesn't matter what authority
says. All that matters is what the mercury does
in the tube. It was a revolution in method. So
we have the calculator. We have atmospheric pressure
in the vacuum. Now we're moving into the early
1650s. His father dies in 1651. Pascal is now
independently wealthy. He's a bachelor living
in Paris. And this is what scholars call his
worldly period. It is. Now, we shouldn't overstate
it. He wasn't some great debauched libertine.
But he definitely enjoyed the finer things in
life for a while. He had a coach and four horses.
He frequented the fashionable salons. And he
fell in with a very specific crowd. You know,
writers, aristocrats, and gamblers. And professional
gamblers, by their very nature, are obsessed
with odds and fairness. They have to be. One
of Pascal's friends was a writer and a man about
town named the Chevalier de Marais. He was a
very keen gambler. And de Marais came to Pascal
with a question that had apparently stumped mathematicians
for centuries. It's famously known as the problem
of points. Okay, what's the scenario here? The
setup is simple. Imagine you and I are playing
a game of chance. Say, flipping a coin. We've
each put 50 gold coins into a pot. The first
person to win five rounds gets the whole hundred
coin pot. Count it. But for some reason, we have
to stop the game early. The candles burn out,
the police raid the gambling den, whatever. And
when we stop, the score is you have won four
rounds and I have only won three rounds. So I'm
ahead. You're ahead. The question is, how do
we divide the hundred coins in the pot in a way
that is perfectly mathematically fair? Well,
the simple answer is just to give it all to me
since I was winning. Or maybe. Maybe split it
based on the ratio of our scores, so a 4 to 3
split. Right, those are the intuitive answers.
But Desmarais and Pascal knew that neither of
those is truly fair, because the fair way to
divide the stakes must depend on the probability
of what would have happened if the game had continued.
Ah, so you're not looking at the past, at the
scores we already have. You're modeling the future.
That is the crucial revolutionary leap. They
are trying to quantify the future. So Pascal...
Intrigued by this, starts a correspondence with
another one of the great minds of the era, Pierre
de Fermat. Who was another one of these brilliant
amateurs. He was a lawyer by trade. A lawyer
in Toulouse. And in a series of letters back
and forth in the summer of 1654, these two men,
Pascal and Fermat, solved it. They realized you
have to map out all the possible future outcomes.
So in our game. If we play one more round. There's
a 50 % chance you win and the game is over. You
take the pot. Okay. And there's a 50 % chance
that I win, in which case the score becomes tied
four to four. Then we'd have to play a final
deciding round. By mapping out this tree of possibilities
and weighing each branch by its probability,
they calculated what they called the expected
value for each player. And this is it. This is
the birth of modern probability theory. This
is the moment. Before this, the future was seen
as the domain of God or fate or just pure blind
luck. It was fundamentally unknowable. Pascal
and Fermat proved that while you can't predict
the specific outcome of a single future event,
you can absolutely predict the pattern of outcomes
over the long run. You can tame uncertainty.
This underpins, I mean, everything in our modern
world. Insurance markets, stock market analysis,
medical trials, election polling, quantum mechanics.
It all starts right here with two French guys
trying to figure out the fair way to split a
gambling pot. And in the middle of all this work,
Pascal decides to synthesize a lot of his thinking
about numbers into his treatise on the arithmetical
triangle. Right. What we all learn in school
as Pascal's triangle. That pyramid of numbers
we've all seen where each number is the sum of
the two numbers directly above it. Now, to be
clear, he didn't invent the triangle itself.
The pattern was known to mathematicians in China,
Persia, and India for centuries before him. But
Pascal was the first person to really explore
all of its properties systematically and write
them down. And he showed how it connected to
probability. He did. He showed that the numbers
in the rows are the binomial coefficients. So
if you want to know, say, how many different
ways can you choose a committee of three people
from a group of five, you just go to the fifth
row of the triangle and the third number is...
and there's your answer. It's a beautiful, elegant
tool. There's one more little mathematical story
from this period involving a toothache. The cycloid.
Yes, though this happens a bit later in 1658
after his major religious conversion. But it
shows his mind was still working on these problems.
He was suffering from a terrible, raging toothache
that kept him awake all night. And just as a
way to distract himself from the pain. A very
Pascal thing to do. Very. He started thinking
about a famous unsolved problem in geometry.
The cycloid. That's the curve traced by a point
on the rim of a rolling wheel. He used geometry
as a painkiller. And it worked. As he got deeper
into the problem, the pain vanished. And he took
this as a divine signal, a sign from God that
it was okay for him to engage in mathematics
as long as it wasn't for vanity. So he solves
it. He solves it in eight days. He figures out
the area under the curve, the volume of the shape
it creates when rotated problems that had stumped
giants like Galileo and Torricelli. And then,
in a very strange move, he held a contest under
a pseudonym, challenging the other great mathematicians
of Europe to solve it. And then he declared himself
the winner of his own contest. It did. It was
a little controversial. Great minds like Christopher
Wren and John Wallace submitted solutions, but
Pascal writing as Amos... Dettenville, judged
his own anonymous solution to be the only fully
correct one. It just shows that even as he was
becoming more religious, he still had that incredibly
sharp, competitive, almost arrogant edge to him.
Absolutely. But that competitive edge was about
to be redirected toward a very, very different
kind of opponent. We have to talk about the great
shift, the event that changed his life forever,
the Night of Fire. Because for all his worldly
success, all the fame from his math and physics,
Pascal was deeply unhappy. He described it as
a period of profound spiritual dryness, even
disgust. He had the money. He had the fame. He
was celebrated in the salons. But he felt this
deep sense of his own wretchedness. And at the
same time, his younger sister Jacqueline, whom
he was very close to, had become a nun at the
Port Royal Abbey. And Port Royal was the absolute
center of a controversial religious movement
called Jansenism. We really need to define Jansenism
because it is the essential backdrop for the
entire second half of Pascal's life. So what
was it? You can think of Jansenism as a very
rigorous, very austere reformist wing within
the Catholic Church. They were heavily influenced
by the writings of St. Augustine. They believed
that human nature was totally and utterly corrupted
after the fall of man in the Garden of Eden.
So we're inherently broken. Utterly broken. We
are incapable of doing any good on our own. We
can only be saved by God's grace, and that grace
is irresistible, but it is given only to a select
few. the elect. You can't earn it. You can't
work your way to heaven. It sounds a lot like
Calvinism, but inside the Catholic Church. It
is very, very similar in its theology to Calvinist
predestination. And that, as you can imagine,
got them into a huge amount of trouble with the
mainstream church, especially with the Pope and
the powerful Jesuit order. But for Pascal, this
rigorous, all or nothing, uncompromising view
of the world. It resonated with his personality.
He was a man of absolutes. So this is all swirling
in his mind. And then we come to the night of
November 23, 1654. Pascal is 31 years old. He's
at his home in Paris. It's late at night. And
from about 10 .30 p .m. to 12 .30 a .m. for two
solid hours, he undergoes some kind of intense,
direct, mystical experience. We don't really
know what happened. We don't. He never spoke
about the details to anyone verbally, but we
know he grabbed a piece of parchment and in a
frantic, ecstatic state, he scrawled down a series
of short, fiery phrases to capture the moment.
And this is the document that we now call the
memorial. Yes. And it starts with the single
word FIRE written in huge capital letters at
the top. And then it says God of Abraham, God
of Isaac, God of Jacob, not of the philosophers
and the scholars. Wow. Not of the philosophers
and the scholars. That is a direct rejection
of his entire life up to that point. Yeah. He's
saying the abstract geometric God of Descartes,
the prime mover. That's not the real God. Not
at all. He goes on. He writes certitude, certitude,
feeling, joy, peace, and then joy, joy, joy,
tears of joy. This wasn't an intellectual conclusion.
This was a visceral, emotional, overwhelming
encounter with a personal deity. And what he
did with this piece of paper is to me the most
telling part of the whole story. He didn't frame
it on his wall. No, he folded it up and he sewed
it into the lining of his coat right over his
heart. And for the rest of his life, whenever
he got a new coat, he would carefully unpick
the seam, take out the precious parchment and
sew it into the new one. He literally kept that
fire close to his heart every single day. A servant
only discovered it by chance after he died. That
moment really marks the death of Pascal the scientist
and the birth of Pascal the religious apologist.
He effectively retires from math and science
and goes to live in seclusion at Port Royal.
Almost immediately, he gets drafted into a war,
a theological war. The Jansenists were under
fierce attack from the Jesuits. The Sorbonne
in Paris was trying to formally censure a leading
Jansenist theologian, Antoine Arnaud. The Jansenists
were losing the public relations battle. They
needed a champion. They needed someone who could
write. So they capped the new guy. They tapped
Pascal. And he produces the provincial letters.
Which are 18 letters written under the brilliant
pseudonym Louis de Montelt, supposedly a symbol
man from Paris writing to his friend back in
the provinces. And they are an absolute masterpiece
of satire and polemic. And he's attacking the
Jesuit method of moral reasoning, which he calls
casuistry. Casuistry. It sounds like casual,
but it's much more complex. Casuistry is case
based ethical reasoning. The Jesuits developed
it as a way to help people navigate complex moral
situations in confession. So on the surface,
it sounds helpful. It can be. But Pascal argued
viciously and brilliantly that the Jesuits were
abusing it. They were using hyper complex hair
splitting logic to create loopholes that could
justify almost any sin. He accused them of being
slimy moral lawyers who could get you off the
hook for murder or theft if you just defined
your intention in the right way. Can you give
us an example of the kind of Jesuitical logic
he was mocking? Oh, absolutely. He has a field
day with it. He mocks the idea that while killing
someone in a formal duel is a mortal sin, you
can get around it by, say, simply going for a
walk in a field where you happen to know your
enemy is waiting. And then if he attacks you,
well, you can kill him in self -defense. It's
all about plausible deniability. Exactly. And
he just shreds this kind of tortured logic. But
the genius of the letters is that he does it
with humor. They are genuinely funny. They're
witty. They're conversational. They're not dense
theological tracks. And this is where we get
that famous quote about brevity, isn't it? It
is. In the 16th letter, he apologizes to his
correspondent, writing, I have made this longer
than usual because I have not had time to make
it shorter. And that captures his style perfectly
lucid, precise, devastatingly efficient. And
these letters became a sensation. They were illegal,
but they were passed around secretly. A black
market bestseller. The king tried to ban them
and have them burned. But everybody in Paris
from the intellectuals to the shopkeepers was
reading them. They completely changed French
prose. Before Pascal, serious Frank writing was
often flowery and dense. Pascal wrote with the
clarity of a geometric proof, but the wit of
a stand -up comedian. Later giants like Voltaire
and Rousseau both pointed to the provincial letters
as the birth of modern French prose. So he successfully
defends his friends. He publicly humiliates the
Jesuits. But he has a much bigger, more ambitious
project in mind. He wants to write a full, comprehensive
defense of the Christian religion. An apology.
This is the great unfinished work of his life.
And it's what eventually became the book we know
today as the Pensée, which just means thoughts.
He never finished it. He died leaving behind
just hundreds of notes and fragments, some meticulously
organized and tied into bundles with string,
others just random phrases jotted on scraps of
paper. So later editors had to piece it all together
like a puzzle. Exactly. Which is why it can be
a challenging read. But even as fragments, they
are just devastatingly powerful. He focuses so
intently on the contradictions of the human condition.
He does. He paints this terrifying picture of
humanity suspended between two infinities, two
abysses. On one side, you have the abyss of the
infinitely large, the silent, terrifying universe
of stars and galaxies that is too big for us
to comprehend. And on the other, the abyss of
the infinitely small, the world of mites and
atoms that we can't see. We're trapped in the
middle, he says, unable to grasp either extreme.
Which leads to his most famous metaphor for humanity.
The thinking reed. Man is only a reed, the weakest
in nature, but he is a thinking reed. It's such
a perfect image. He fully acknowledges our physical
fragility. A vapor, a drop of water. The universe
doesn't have to arm itself to crush us. It's
easy. Right. But our dignity, our greatness lies
entirely in our thought. We know that we are
dying. We know the universe is crushing us. The
universe, he says, knows nothing of this. That
consciousness, that awareness of our own wretchedness
is what elevates us. And it's from this analysis
of the human condition, the state of being lost,
confused, and self -aware, that he produces the
most famous and certainly the most controversial
part of the Pensees. The wager. Pascal's wager,
yes. And it's so often misunderstood. People
think it's supposed to be a logical proof of
God's existence. It's not. He didn't think you
could prove God with reason. He explicitly believed
you couldn't. He thought the distance between
our finite minds and an infinite God was, well,
infinite. Reason is powerless. So he reframes
the question. This is not a logic problem. It's
a decision problem. A gamble. He brings the gambler
from his worldly period back into his theology.
He absolutely does. He imagines he's talking
to a skeptic, a friend from the salons, who says,
I just don't know if God exists or not, so I'm
not going to choose. I will suspend judgment.
I won't bet. Which seems like a reasonable position.
It does. But Pascal's brilliant move is to say,
you can't suspend judgment. You have no choice.
You are already embarked. You are alive. Your
life is moving forward toward death. You are
already in the game. You must place a bet. So
he draws up the betting matrix. Let's walk through
the four quadrants of the wager. Okay. Quadrant
one. You choose to bet that God exists, and it
turns out you're right. He does exist. What's
the result? Infinite gain. Eternal happiness,
heaven. Okay. Quadrant two, you bet God exists
and it turns out you're wrong. He doesn't. What
did you lose? A finite loss. You lived a virtuous
life. Maybe you missed out on some parties or
pleasures. Then you died and that was it. You
lost a few earthly experiences. Right. A limited
finite loss. Now, the other side. Quadrant three,
you bet that God does not exist and you're wrong.
He does exist. Infinite loss. Damnation. Losing
out on everything that matter. The ultimate bad
outcome. And finally, quadrant four. You bet
God doesn't exist. And you're right. A finite
gain. You enjoyed those parties you otherwise
would have missed. You died. And that was it.
So when you lay it out like that, it becomes
a problem of probability and expected value,
just like the problem of points. You have a choice
between a finite risk for a potentially infinite
reward on one side and a finite reward for a
potentially infinite risk on the other. And Pascal's
conclusion is that no rational gambler, no sane
person would ever bet against the infinite. Even
if you think the probability of God existing
is tiny, one in a billion, the potential infinite
payoff still makes it the only rational bet.
The expected value of believing is always infinite.
That's the cold, hard logic of it. But people,
and I include myself here, people have always
had a problem with this argument. It feels cold.
It feels cynical, mercenary. It feels transactional.
I'll believe just in case to cover my bet. Right.
And it feels like you're just faking it. You
can't just decide to believe something because
it's a good bet. And Pascal, brilliant psychologist
that he was, anticipated this objection completely.
He has his skeptics say, OK, I'm convinced by
the logic, but I can't make myself believe. What
do I do? And Pascal's advice is chillingly practical.
He says, if you want to believe but can't, you
must cure yourself of your passions, which are
the obstacle. Start acting as if you believe.
Go through the motions. Yes. Go to mass. Take
the holy water. Mumble the prayers, he calls
it a betir, which literally means to stupefy
yourself or to make yourself like a beast, like
the unthinking faithful peasants. He argues that
by taming your skeptical intellect through habit
and ritual, genuine faith might eventually follow.
It's fake it till you make it, applied to the
salvation of your soul. It's a profound psychological
insight. He understood, perhaps better than anyone,
that belief isn't always a purely intellectual
switch you can flip. It's a habit of the heart,
and habits are formed through action. So we are
nearing the end of his short life now. He is
wracked with illness. He's coring his soul into
these fragmented thoughts. But he has one last
surprising invention left in him. In 1662, the
very year he dies, he decides to fix the traffic
problem in Paris. It's just the most wonderful
and unexpected final act. The Carassas à Saint
-Saëns, the five sole carriages. Pascal looked
at the city of Paris and he saw a problem of
logistics and social equity. If you were poor,
you walked everywhere. If you were rich, you
had a private carriage. There was no middle ground.
So he invents the public bus system. He basically
does. He, along with some powerful friends like
the Duke of Rennes, formed a company. They got
a royal patent. He designed a system of large
multi passenger carriages that would run on fixed
rides across Paris for a fixed price of five
souls. But the truly revolutionary part, the
part that makes it modern was. the schedule.
That was the genius of it. The carriages left
at specific regular times, regardless of whether
they were full or empty. Which is the single
defining feature of true public transit, reliability.
You know the bus will be there. It was an instant
success. The first line opened in March of 1662.
There were crowds in the streets cheering for
it. It was a sensation. Pascal had even stipulated
in the plans that the profits should go to the
poor and that the poor must be allowed to ride.
It just goes to show that his mind never, ever
turned off. Whether it was the abstract geometry
of a hexagon or the practical logistics of moving
people across a city, he saw systems and he wanted
to optimize them. But he didn't live to see his
bus line flourish. By the summer of 1662, his
health had completely collapsed. He was in constant
agony. Do we know what was actually wrong with
him physically? It's very difficult to diagnose
retrospectively from 400 years away. But the
consensus is that it was likely a combination
of stomach cancer and malignant tuberculosis.
He had terrible stomach ulcers. The autopsy that
was performed revealed grave damage to his stomach,
his liver, and they even found lesions on his
brain. And yet in those agonizing final months,
his religious is set. It did. He sold his fine
furniture and his carriage to give the money
to the poor. He had moved into his sister's house,
but he begged her to let him be taken to a hospital
for the incurables so that he could die among
the poorest of the poor. They refused. He was
simply too sick and unstable to be moved. He
spent his final days in and out of consciousness,
suffering from terrible convulsions and pain.
He made his last confession, he received communion,
and his last recorded words were, May God never
abandon me. He died on August 19, 1662. Gone
at 39. 39. The legacy he leaves behind is, well,
it's fragmented, just like his pensées. It's
everywhere. We use the Pascal as the SI unit
of pressure. There's a major programming language
named Pascal. Computer chip architectures are
named after him. And we use his probability theory
every single time we check a weather forecast
or read a political poll. And we use his arguments
or argue against them every time we debate the
existence of God. And in a deeper sense, we still
struggle with the same core problems he did.
We're all still thinking reeds, aware of our
own mortality, often terrified by the silent,
infinite spaces of the universe, distracting
ourselves with our own modern versions of gambling
and bus schedules. That's the enduring power
of Pascal. He seems to have seen the modern condition,
our condition, before modernity had even properly
begun. He saw that science would give us immense
power, but it wouldn't and couldn't give us peace.
I think I want to end with that famous thought
of his. He wrote, all of humanity's problems
stem from man's inability to sit quietly in a
room alone. Divertissement. the constant need
to be doing something, to be entertained, so
that we don't have to face the big questions,
to face ourselves. So a final thought for all
of you listening. Maybe after this is over, just
for a few minutes, turn everything off, sit in
a room, be quiet, and see what happens. It might
be the hardest experiment Pascal ever proposed.
Thank you for joining us for this deep dive.
We'll see you next time.