WEBVTT 00:00:00.000 --> 00:00:02.100 Welcome back to the Deep Dive. We're so glad 00:00:02.100 --> 00:00:04.280 you're here with us. It's great to be back. Today 00:00:04.280 --> 00:00:07.589 we are looking at a figure who, um... Honestly, 00:00:07.730 --> 00:00:10.390 he sort of defies the usual boxes we like to 00:00:10.390 --> 00:00:12.669 put historical figures in. He really does. You 00:00:12.669 --> 00:00:14.949 know, you usually have your science guys over 00:00:14.949 --> 00:00:17.530 here, your Newtons, your Galileos, your Einsteins. 00:00:17.670 --> 00:00:19.870 And then in a completely different building, 00:00:19.989 --> 00:00:22.250 sometimes on a different planet, you have your 00:00:22.250 --> 00:00:25.289 philosophers, your theologians. Yeah, your Krippegards, 00:00:25.329 --> 00:00:28.030 your Augustans. Exactly. And they don't usually 00:00:28.030 --> 00:00:29.989 talk to each other. They operate in different 00:00:29.989 --> 00:00:32.670 worlds. Well, Stephen Jay Gould had that phrase, 00:00:32.890 --> 00:00:35.850 non -overlapping magisteria. That's how it's 00:00:35.850 --> 00:00:38.869 supposed to work. But today's subject, he didn't 00:00:38.869 --> 00:00:41.530 just overlap them. He smashed them together. 00:00:41.850 --> 00:00:44.530 We are talking about Blaise Pascal. Blaise Pascal. 00:00:44.789 --> 00:00:48.090 And the sheer scope of his life is just staggering 00:00:48.090 --> 00:00:50.229 when you think about it. A man who lived only 00:00:50.229 --> 00:00:52.429 39 years. I mean, that's the first thing that 00:00:52.429 --> 00:00:55.950 hits you. Born in 1623, gone by 1662. A very 00:00:55.950 --> 00:00:59.270 short window. And in that brief window, he managed 00:00:59.270 --> 00:01:02.289 to live what feels like three or four completely 00:01:02.289 --> 00:01:06.450 distinct, brilliant lives. He invents the mechanical 00:01:06.450 --> 00:01:08.769 calculator when he's basically still a teenager. 00:01:09.090 --> 00:01:11.569 To help his dad with his taxes, no less? Right. 00:01:11.849 --> 00:01:14.670 Then he lays the groundwork for probability theory. 00:01:14.870 --> 00:01:17.170 Yeah. All because a gambler friend asked him 00:01:17.170 --> 00:01:19.269 a question about a game. A very practical problem. 00:01:19.510 --> 00:01:22.560 And he revolutionizes physics. By proving that 00:01:22.560 --> 00:01:24.939 the atmosphere, the air around us, actually has 00:01:24.939 --> 00:01:29.500 weight. Yeah. And then, after all that, he just 00:01:29.500 --> 00:01:32.120 pivots. Yeah. He abandons science to become one 00:01:32.120 --> 00:01:34.019 of the most profound, most challenging religious 00:01:34.019 --> 00:01:36.900 writers in the entire Western canon. It is a 00:01:36.900 --> 00:01:39.689 dizzying resume. I mean, it really is. And the 00:01:39.689 --> 00:01:41.769 thing that makes Pascal so compelling, so fascinating 00:01:41.769 --> 00:01:43.829 to dive into, is that he isn't just a jack of 00:01:43.829 --> 00:01:46.310 all trades. He was a master of all of them. He 00:01:46.310 --> 00:01:48.590 didn't just dabble. When he decided to do math, 00:01:48.750 --> 00:01:50.969 he fundamentally changed mathematics. When he 00:01:50.969 --> 00:01:53.450 turned to physics, he broke a 2 ,000 -year -old 00:01:53.450 --> 00:01:56.370 Aristotelian consensus. And when he finally turned 00:01:56.370 --> 00:01:59.530 his mind to God, he wrote this collection of 00:01:59.530 --> 00:02:02.469 fragments, the Pensées, that philosophers and 00:02:02.469 --> 00:02:04.549 theologians are still fiercely arguing about 00:02:04.549 --> 00:02:07.680 400 years later. So the mission for this deep 00:02:07.680 --> 00:02:10.520 dive then is to try and figure out how all those 00:02:10.520 --> 00:02:13.159 pieces fit together. Because on the surface, 00:02:13.379 --> 00:02:15.939 the person who invents a calculating machine 00:02:15.939 --> 00:02:18.740 seems like a completely different person from 00:02:18.740 --> 00:02:21.740 the guy who secretly sows a prayer into the lining 00:02:21.740 --> 00:02:24.340 of his coat. It seems like a contradiction. It 00:02:24.340 --> 00:02:26.199 does. But I have a feeling you're going to tell 00:02:26.199 --> 00:02:27.979 me they're actually the same person driven by 00:02:27.979 --> 00:02:29.939 the same thing. They absolutely are. I think 00:02:29.939 --> 00:02:32.060 the common thread, the engine driving him through 00:02:32.060 --> 00:02:33.960 all these different fields was this relentless, 00:02:34.080 --> 00:02:37.729 almost. almost desperate pursuit of certainty, 00:02:37.990 --> 00:02:40.889 of truth. Whether he was looking for truth in 00:02:40.889 --> 00:02:43.789 the precise meshing of gears in a machine, or 00:02:43.789 --> 00:02:46.629 in the empty space of a glass tube, or in the 00:02:46.629 --> 00:02:50.270 silent contemplation of a monastery, he was applying 00:02:50.270 --> 00:02:53.050 the same rigorous, uncompromising, analytical 00:02:53.050 --> 00:02:55.669 intellect. He just wanted to know what was real. 00:02:55.849 --> 00:02:57.469 Let's start at the beginning then, because the 00:02:57.469 --> 00:03:00.949 origin story here feels absolutely vital to understanding 00:03:00.949 --> 00:03:04.639 the man. Blaise Pascal. Born in Clermont -Ferrand, 00:03:04.740 --> 00:03:08.319 France. June 19, 1623. His mother passes away 00:03:08.319 --> 00:03:10.539 when he's just a toddler, only three years old. 00:03:11.099 --> 00:03:13.819 So he's raised almost entirely by his father, 00:03:14.000 --> 00:03:16.900 Etienne Pascal. And Etienne is a fascinating, 00:03:17.159 --> 00:03:19.659 crucial character in his own right. He wasn't 00:03:19.659 --> 00:03:21.800 just some bureaucrat. He was a tax collector, 00:03:22.000 --> 00:03:24.699 yes. But he was also a member of the Noblesse 00:03:24.699 --> 00:03:27.620 de Robe, which was the administrative nobility. 00:03:27.800 --> 00:03:30.699 So an educated man. A powerful man. Very. And 00:03:30.699 --> 00:03:32.860 an amateur mathematician himself. He was very 00:03:32.860 --> 00:03:34.960 well connected in the intellectual circles of 00:03:34.960 --> 00:03:37.219 Paris at the time. When Blaise was about eight 00:03:37.219 --> 00:03:39.819 years old, Etienne actually moves the family, 00:03:39.919 --> 00:03:42.520 that's Blaise and his two sisters, Gilbert and 00:03:42.520 --> 00:03:44.319 Jacqueline, to Paris. And he makes this really 00:03:44.319 --> 00:03:46.800 interesting decision to homeschool them, which, 00:03:46.879 --> 00:03:49.000 I mean, in the 17th century, that's not exactly 00:03:49.000 --> 00:03:51.139 the norm. Not at all. But Etienne had a very 00:03:51.139 --> 00:03:54.340 specific, very rigid curriculum in mind. And 00:03:54.340 --> 00:03:56.340 the most famous part of that curriculum was what 00:03:56.340 --> 00:03:59.419 it was missing, mathematics. He had this idea, 00:03:59.560 --> 00:04:02.539 this pedagogical theory, that a child's mind 00:04:02.539 --> 00:04:04.719 should be trained first on languages and the 00:04:04.719 --> 00:04:07.680 humanities, Latin, Greek. He thought mathematics 00:04:07.680 --> 00:04:10.500 was too compelling, too absorbing. Maybe even 00:04:10.500 --> 00:04:13.159 too taxing for a young mind. He thought it would 00:04:13.159 --> 00:04:15.759 be a distractor. Total distraction. So he literally 00:04:15.759 --> 00:04:18.899 banned geometry from the house. He hid the textbooks. 00:04:19.000 --> 00:04:21.800 He told Blaze flat out, you are not to think 00:04:21.800 --> 00:04:24.240 about mathematics until you are at least 15. 00:04:24.819 --> 00:04:27.100 Which, I mean, if you know anything about raising 00:04:27.100 --> 00:04:29.779 a curious child, that is the single worst tactic 00:04:29.779 --> 00:04:32.480 you could possibly employ. That's a colossal 00:04:32.480 --> 00:04:35.339 tactical error. You tell a brilliant kid that 00:04:35.339 --> 00:04:37.240 something is forbidden. It becomes the only thing 00:04:37.240 --> 00:04:39.300 they want. The most interesting thing in the 00:04:39.300 --> 00:04:41.600 world. Precisely. It became the forbidden fruit. 00:04:41.879 --> 00:04:44.199 So Blaze starts asking questions. What is geometry? 00:04:44.420 --> 00:04:46.959 What does it even do? And his father gives him 00:04:46.959 --> 00:04:49.740 this very vague general answer. Something like, 00:04:49.819 --> 00:04:52.300 oh, it's the study of how to make precise figures 00:04:52.300 --> 00:04:54.500 and find the relationships between their parts. 00:04:54.779 --> 00:04:56.620 And that was all he needed. That was enough. 00:04:56.759 --> 00:04:59.360 The fuse was lit. And this leads directly to 00:04:59.360 --> 00:05:02.300 what might be the most famous story about Pascal's 00:05:02.300 --> 00:05:06.040 childhood. The kitchen floor incident. Right. 00:05:06.100 --> 00:05:08.079 He's 12 years old at this point. About 12, yes. 00:05:08.379 --> 00:05:10.899 And Etienne comes home one day to find his son 00:05:10.899 --> 00:05:13.199 on the floor with a piece of charcoal drying 00:05:13.199 --> 00:05:16.100 on the tiles. Just doodling, he probably thought. 00:05:16.220 --> 00:05:19.720 At first, maybe. But he watches for a bit. And 00:05:19.720 --> 00:05:22.279 he sees Blaise's drawing shapes, circles, triangles, 00:05:22.620 --> 00:05:25.829 lines. But here's the thing. Because no one had 00:05:25.829 --> 00:05:28.470 ever taught him the official words, he was making 00:05:28.470 --> 00:05:30.649 up his own language for it. Oh, that's incredible. 00:05:30.930 --> 00:05:33.189 He called a circle around. He called a line a 00:05:33.189 --> 00:05:36.370 bar. He was building his own private lexicon 00:05:36.370 --> 00:05:39.350 for geometry. So he's not just drawing. He's 00:05:39.350 --> 00:05:42.089 doing so much more. Etienne realizes that Blaise 00:05:42.089 --> 00:05:43.930 isn't just making pictures. He's constructing 00:05:43.930 --> 00:05:47.089 proofs. He is, from first principles, working 00:05:47.089 --> 00:05:49.670 his way through Euclidean geometry. Without a 00:05:49.670 --> 00:05:52.110 textbook. Without a teacher. Completely on his 00:05:52.110 --> 00:05:54.910 own, by the time his father found him, he had 00:05:54.910 --> 00:05:57.310 allegedly, and this is according to his sister 00:05:57.310 --> 00:06:00.769 Gilbert's account, he had independently rediscovered 00:06:00.769 --> 00:06:03.930 and proven the first 32 propositions of Euclid's 00:06:03.930 --> 00:06:05.790 elements. Okay, let's just pause on that for 00:06:05.790 --> 00:06:08.670 a second. The 32nd proposition of Euclid is the 00:06:08.670 --> 00:06:10.490 one that says the sum of the angles in a triangle 00:06:10.490 --> 00:06:14.350 equals two right angles. Yes. 180 degrees. Yes. 00:06:14.709 --> 00:06:17.930 He derived that from scratch using charcoal on 00:06:17.930 --> 00:06:20.910 a tile floor. At 12 years old. That is the story 00:06:20.910 --> 00:06:23.029 that has come down to us. Now, you know, modern 00:06:23.029 --> 00:06:25.430 historians might debate whether he reconstructed 00:06:25.430 --> 00:06:27.410 the entire sequence perfectly or if he was just 00:06:27.410 --> 00:06:29.930 grasping the core logic of it. But either way, 00:06:30.050 --> 00:06:33.490 the intellectual achievement is just, it's staggering. 00:06:33.689 --> 00:06:35.850 It's off the charts. He deduced the axioms of 00:06:35.850 --> 00:06:39.009 geometry alone in a room. And when Etienne realized 00:06:39.009 --> 00:06:41.350 what was happening, that his son had effectively 00:06:41.350 --> 00:06:44.509 reinvented 2000 years of Greek mathematics in 00:06:44.509 --> 00:06:47.620 their living room, the story goes. That he wept. 00:06:47.660 --> 00:06:49.620 He must have realized he couldn't stop it. He 00:06:49.620 --> 00:06:52.459 knew. He gave up. He went and got Blaze a copy 00:06:52.459 --> 00:06:54.560 of Euclid's Elements, and Blaze, of course, just 00:06:54.560 --> 00:06:57.399 devoured it in a matter of days. And that just 00:06:57.399 --> 00:06:59.639 opened the floodgates. Because it wasn't long 00:06:59.639 --> 00:07:01.980 after that, I mean, he's still a teenager, that 00:07:01.980 --> 00:07:04.160 he's not just learning math anymore. He's contributing 00:07:04.160 --> 00:07:07.949 to it. At 16, he writes the essay on conics. 00:07:08.089 --> 00:07:11.009 On conic sections. Which is a short but incredibly 00:07:11.009 --> 00:07:14.829 dense treatise on conic sections. You know, ellipses, 00:07:14.949 --> 00:07:17.370 parabolas, hyperbolas, all the shapes you get 00:07:17.370 --> 00:07:20.529 by slicing through a cone. And inside this essay, 00:07:20.730 --> 00:07:24.610 he presents something new, what we now call Pascal's 00:07:24.610 --> 00:07:27.610 theorem. Or the mystic hexagram, which is a much 00:07:27.610 --> 00:07:29.649 better name. It is a great name. Explain that 00:07:29.649 --> 00:07:33.149 to us. What is the mystic hexagram? Okay, so 00:07:33.149 --> 00:07:35.490 it's a foundational concept in a field called 00:07:35.490 --> 00:07:39.420 projective geometry. Imagine you have any conic 00:07:39.420 --> 00:07:41.819 section, let's just say an oval to make it easy. 00:07:41.939 --> 00:07:44.680 Now you draw a hexagon inside it so that all 00:07:44.680 --> 00:07:47.459 six of its corners or vertices are touching the 00:07:47.459 --> 00:07:49.899 edge of the oval. Hexagon can be all skewed and 00:07:49.899 --> 00:07:51.519 irregular, right? Totally irregular. It doesn't 00:07:51.519 --> 00:07:54.079 matter. Now take the opposite sides of that hexagon 00:07:54.079 --> 00:07:56.079 and extend them out like lines until they cross 00:07:56.079 --> 00:07:58.100 each other. You'll get three intersection points. 00:07:58.839 --> 00:08:01.480 Pascal proved that those three points will always 00:08:01.480 --> 00:08:04.139 lie on a single straight line. No matter how 00:08:04.139 --> 00:08:06.220 you draw the hexagon. No matter how you draw 00:08:06.220 --> 00:08:08.540 it, it feels like magic when you see it drawn 00:08:08.540 --> 00:08:11.120 out. It's this hidden order. And it's important 00:08:11.120 --> 00:08:13.160 to remember, this was cutting edge stuff. This 00:08:13.160 --> 00:08:15.660 wasn't just solving odd problems. This was creating 00:08:15.660 --> 00:08:19.779 new mathematics. He sent his paper to Father 00:08:19.779 --> 00:08:22.939 Marine Mersenne in Paris. Who was like the central 00:08:22.939 --> 00:08:26.220 node of the European scientific internet at the 00:08:26.220 --> 00:08:28.740 time. He was the guy. He connected everyone. 00:08:29.060 --> 00:08:31.660 And Mersenne, of course, shows it to the biggest 00:08:31.660 --> 00:08:34.769 name in the game. Rene Descartes. The I think, 00:08:34.769 --> 00:08:38.309 therefore I am guy. The philosophical heavyweight. 00:08:38.389 --> 00:08:40.809 And you'd think he'd be blown away by this, but... 00:08:41.210 --> 00:08:43.409 He wasn't. He was skeptical. In fact, he was 00:08:43.409 --> 00:08:45.830 worse than skeptical. He was dismissive. When 00:08:45.830 --> 00:08:47.730 Mersenne showed him the essay, Descartes' first 00:08:47.730 --> 00:08:51.009 reaction was, I do not believe a 16 -year -old 00:08:51.009 --> 00:08:52.769 wrote this. He thought the father wrote it. He 00:08:52.769 --> 00:08:55.110 assumed it was Etienne, the father, trying to 00:08:55.110 --> 00:08:57.230 pass off his own work to build up the family 00:08:57.230 --> 00:08:59.830 name. He just couldn't accept that this level 00:08:59.830 --> 00:09:03.049 of mature, abstract reasoning could come from 00:09:03.049 --> 00:09:05.409 a boy. That's sort of the ultimate backhanded 00:09:05.409 --> 00:09:07.649 compliment, isn't it? This is too good to be 00:09:07.649 --> 00:09:10.710 yours. It really is. And even after he was finally 00:09:10.710 --> 00:09:12.710 convinced that, yes, the kid actually wrote it, 00:09:12.789 --> 00:09:15.649 Descartes was still sniffy about it. He said 00:09:15.649 --> 00:09:17.909 something along the lines of, well, I can see 00:09:17.909 --> 00:09:19.870 how a boy might stumble onto this one little 00:09:19.870 --> 00:09:22.029 proof, but he won't go much further with it. 00:09:22.169 --> 00:09:24.830 Wow. It just shows you, I think, the tension 00:09:24.830 --> 00:09:28.289 between the established, rigid, Cartesian way 00:09:28.289 --> 00:09:31.330 of thinking and this intuitive, almost frightening 00:09:31.330 --> 00:09:34.590 brilliance of Pascal. So by 16, he's already 00:09:34.590 --> 00:09:37.350 a mathematical prodigy. He's gotten the attention 00:09:37.350 --> 00:09:39.490 and the scorn of the most famous philosopher 00:09:39.490 --> 00:09:43.929 in Europe. But then, real life... sort of intrudes. 00:09:43.929 --> 00:09:46.330 His father, Etienne, gets a new government post. 00:09:46.549 --> 00:09:48.269 Right. This is a crucial shift in the story. 00:09:48.470 --> 00:09:50.429 Etienne had briefly fallen out of favor with 00:09:50.429 --> 00:09:52.669 the powerful Cardinal Richelieu, but he gets 00:09:52.669 --> 00:09:55.710 reinstated and is sent to Rouen in Normandy to 00:09:55.710 --> 00:09:58.230 be the king's tax commissioner. And Rouen at 00:09:58.230 --> 00:10:00.289 this time was a mess. A total mess. There had 00:10:00.289 --> 00:10:03.110 been tax revolts. The city was in chaos. And 00:10:03.110 --> 00:10:05.529 Etienne's job was to go through years of disorganized 00:10:05.529 --> 00:10:08.049 records and figure out who owed what. He had 00:10:08.049 --> 00:10:10.309 to assess and collect taxes from thousands of 00:10:10.309 --> 00:10:12.850 people. And the sheer volume... of the arithmetic 00:10:12.850 --> 00:10:15.690 was, well, was crushing. You have to picture 00:10:15.690 --> 00:10:19.149 the scene, right? Night after night, the father 00:10:19.149 --> 00:10:22.149 is just hunched over a desk, buried in ledgers, 00:10:22.230 --> 00:10:25.149 surrounded by flickering candlelight, doing endless 00:10:25.149 --> 00:10:27.309 columns of addition and subtraction by hand. 00:10:27.490 --> 00:10:30.169 And Blaze, who's now about 19, sees his father 00:10:30.169 --> 00:10:32.629 just suffering under this mountain of labor, 00:10:32.769 --> 00:10:35.169 and he decides he's going to help. But he doesn't 00:10:35.169 --> 00:10:37.049 just offer to, you know, double -check the swims. 00:10:37.090 --> 00:10:40.279 No. He thinks, I can build a machine to do this 00:10:40.279 --> 00:10:42.620 for him. I will mechanize this mental drudgery. 00:10:42.799 --> 00:10:45.779 This is the birth of the Pascaline, the mechanical 00:10:45.779 --> 00:10:48.220 calculator. And I think we often just gloss over 00:10:48.220 --> 00:10:50.539 this. We say he built a calculator, but we really 00:10:50.539 --> 00:10:53.179 need to understand what an engineering nightmare 00:10:53.179 --> 00:10:56.100 this must have been in the 1640s. It was a nightmare. 00:10:56.639 --> 00:10:58.240 Because this isn't a simple machine that just 00:10:58.240 --> 00:11:00.159 adds one plus one. Right, because of the money 00:11:00.159 --> 00:11:02.940 system. Exactly. France wasn't using a nice, 00:11:02.960 --> 00:11:06.019 clean decimal system. They were using livre, 00:11:06.299 --> 00:11:09.320 sol, and denier. Walk us through how that works. 00:11:09.419 --> 00:11:11.659 It's confusing. Okay, so livre was the main unit, 00:11:11.720 --> 00:11:13.679 sort of like a dollar or a pound. But there were 00:11:13.679 --> 00:11:16.120 20 sols in a single livre. And then there were 00:11:16.120 --> 00:11:18.539 12 deniers and a single sole. So it's base 12, 00:11:18.679 --> 00:11:20.779 then base 20, then base 10 for the rest. Exactly. 00:11:20.799 --> 00:11:23.100 So if you're building a machine to add this up, 00:11:23.159 --> 00:11:25.279 you can't just have every gear have 10 teeth. 00:11:25.480 --> 00:11:28.360 You need a gear with 12 teeth for the deniers, 00:11:28.460 --> 00:11:31.440 which then has to turn a gear with 20 teeth for 00:11:31.440 --> 00:11:33.360 the soles, which then has to turn the lever gears. 00:11:33.679 --> 00:11:35.419 And they all have to work in perfect sync. In 00:11:35.419 --> 00:11:38.100 sync. And the real killer, the problem that had 00:11:38.100 --> 00:11:40.519 stumped everyone before, was the carry mechanism. 00:11:41.039 --> 00:11:42.879 You mean like when you're adding and you get 00:11:42.879 --> 00:11:46.139 to nine? You ride a zero and carry the one? Precisely. 00:11:46.139 --> 00:11:49.159 On the machine, if your sole's wheel is at 19 00:11:49.159 --> 00:11:51.679 and you add one more sole, that wheel has to 00:11:51.679 --> 00:11:54.379 click over to zero and it has to give a push 00:11:54.379 --> 00:11:56.639 to the next wheel, the lever wheel, to move it 00:11:56.639 --> 00:11:59.000 forward by one. So it's a chain reaction. It 00:11:59.000 --> 00:12:02.740 is. And if you have a number like 9 ,999 lever 00:12:02.740 --> 00:12:05.600 and you add one, you have to carry across four 00:12:05.600 --> 00:12:10.000 or five heavy brass gears all at once. The cumulative 00:12:10.000 --> 00:12:12.779 friction, the force required, would jam any simple 00:12:12.779 --> 00:12:14.860 machine. would just lock up. It's like a domino 00:12:14.860 --> 00:12:17.120 effect of friction and force. So how did he solve 00:12:17.120 --> 00:12:20.460 it? He invented a mechanism of pure genius. It's 00:12:20.460 --> 00:12:23.220 called the sautoir. It's basically a little gravity 00:12:23.220 --> 00:12:26.179 -assisted pawl, like a tiny weighted lever. As 00:12:26.179 --> 00:12:28.379 you turn a number wheel, it slowly lifts this 00:12:28.379 --> 00:12:30.600 little weight. Okay. Then, right when the wheel 00:12:30.600 --> 00:12:33.559 clicks past its final number, say, from 11 to 00:12:33.559 --> 00:12:36.220 0 on the denier's wheel, that little weighted 00:12:36.220 --> 00:12:39.659 lever drops. And the energy from that falling 00:12:39.659 --> 00:12:42.159 weight provides the kick, the little burst of 00:12:42.159 --> 00:12:44.740 force needed to turn the next wheel one notch. 00:12:44.919 --> 00:12:47.820 So he's isolating the force. He's isol - he's 00:12:47.820 --> 00:12:51.139 using gravity as a tiny temporary battery for 00:12:51.139 --> 00:12:53.720 each individual carry. It meant the user felt 00:12:53.720 --> 00:12:55.679 the same easy resistance whether they were adding 00:12:55.679 --> 00:13:00.220 one to one or one to 9 ,999. That is just so 00:13:00.220 --> 00:13:02.419 clever. But it must have been incredibly difficult 00:13:02.419 --> 00:13:04.679 to actually build. Oh, it was a torment. The 00:13:04.679 --> 00:13:07.820 metalworking skills in the 1640s, they just weren't 00:13:07.820 --> 00:13:09.759 up to the kind of precision that Pascal needed. 00:13:09.919 --> 00:13:12.679 He went through more than 50 prototypes. He had 00:13:12.679 --> 00:13:14.799 to personally stand over the blacksmiths and 00:13:14.799 --> 00:13:16.700 the clockmakers because they kept getting the 00:13:16.700 --> 00:13:19.080 tolerances wrong. He spends three years on this, 00:13:19.159 --> 00:13:21.840 right? He finally gets a working model in 1645. 00:13:22.340 --> 00:13:25.580 He even gets a royal patent from the king. This 00:13:25.580 --> 00:13:27.360 should have been a world -changing invention. 00:13:27.720 --> 00:13:29.919 And technologically, it was. It was the first 00:13:29.919 --> 00:13:32.600 truly functional calculator that could be operated 00:13:32.600 --> 00:13:35.799 by a non -expert. It worked. But as a business. 00:13:36.179 --> 00:13:38.919 A disaster. A complete and total disaster. A 00:13:38.919 --> 00:13:42.220 commercial failure. Why? I don't get that. If 00:13:42.220 --> 00:13:44.659 it saves so much time and effort, why didn't 00:13:44.659 --> 00:13:47.700 every accountant and merchant in France buy one? 00:13:48.009 --> 00:13:52.090 Two main reasons. First, the cost. It was outrageously, 00:13:52.110 --> 00:13:55.129 exorbitantly expensive. The fine materials, the 00:13:55.129 --> 00:13:58.330 precision labor. A single Pascaline cost more 00:13:58.330 --> 00:14:00.409 than most skilled craftsmen earned in a lifetime. 00:14:00.669 --> 00:14:03.070 So it becomes a status symbol. Exactly. It became 00:14:03.070 --> 00:14:05.889 a toy for the aristocracy. If you were a wealthy 00:14:05.889 --> 00:14:07.950 duke, you'd have a Pascaline on your desk to 00:14:07.950 --> 00:14:10.009 show off his cleverness to your friends, but 00:14:10.009 --> 00:14:11.470 you probably weren't using it to actually do 00:14:11.470 --> 00:14:13.610 your estate accounts. It's the original expensive 00:14:13.610 --> 00:14:15.889 tech gadget that nobody really needed, but everyone 00:14:15.889 --> 00:14:19.019 wanted on their desk. It absolutely is. And there 00:14:19.019 --> 00:14:21.519 was also, interestingly, some resistance from 00:14:21.519 --> 00:14:23.980 the clerks and accountants themselves, a bit 00:14:23.980 --> 00:14:26.620 of fear of job replacement. They worried this 00:14:26.620 --> 00:14:29.100 machine would make them obsolete. The first fears 00:14:29.100 --> 00:14:31.200 of automation. You could say that. In the end, 00:14:31.220 --> 00:14:33.679 only about 20 finished machines were ever built 00:14:33.679 --> 00:14:36.340 over a decade. But the legacy, of course, is 00:14:36.340 --> 00:14:39.539 massive. Pascal proved that mental labor calculation 00:14:39.539 --> 00:14:42.879 could be mechanized. He's really one of the grandfathers 00:14:42.879 --> 00:14:45.120 of computer hardware. So he's conquered theoretical 00:14:45.120 --> 00:14:48.100 math. He's basically invented hardware engineering. 00:14:49.019 --> 00:14:51.120 Now let's pivot to the next big phase of his 00:14:51.120 --> 00:14:55.159 life. We're in the late 1640s now. The family 00:14:55.159 --> 00:14:58.559 has moved back to Paris. And Pascal gets fascinated 00:14:58.559 --> 00:15:02.240 by physics. Specifically, the physics of nothing. 00:15:02.539 --> 00:15:04.600 The physics of the void. This was one of the 00:15:04.600 --> 00:15:06.820 hottest, most contentious scientific debates 00:15:06.820 --> 00:15:09.039 of the entire 17th century. The nature of the 00:15:09.039 --> 00:15:11.519 vacuum. And the prevailing wisdom going all the 00:15:11.519 --> 00:15:14.019 way back to Aristotle. was horror vacuuming. 00:15:14.039 --> 00:15:16.860 Nature abhors a vacuum. We hear that phrase a 00:15:16.860 --> 00:15:19.200 lot, but what did that actually mean to them? 00:15:19.240 --> 00:15:21.480 Was it just a poetic way of speaking? No, no, 00:15:21.500 --> 00:15:24.120 they took it absolutely literally. Aristotle 00:15:24.120 --> 00:15:26.179 and his followers, which included Descartes, 00:15:26.179 --> 00:15:29.019 by the way, believe that space is a plenum. It 00:15:29.019 --> 00:15:31.500 is completely full. There are no empty gaps. 00:15:31.799 --> 00:15:34.460 If you move an object, air, or some other invisible 00:15:34.460 --> 00:15:38.039 matter, an ether instantly, magically rushes 00:15:38.039 --> 00:15:41.220 in to fill the space. So for them, A true void, 00:15:41.419 --> 00:15:44.200 true nothingness was physically impossible. And 00:15:44.200 --> 00:15:46.360 maybe even theologically impossible, because 00:15:46.360 --> 00:15:49.000 if God is omnipresent, how can there be a place 00:15:49.000 --> 00:15:52.759 where nothing, not even God, exists? So asserting 00:15:52.759 --> 00:15:55.600 that nothing could exist was a deeply controversial, 00:15:55.820 --> 00:15:58.740 even dangerous idea. But then Pascal hears about 00:15:58.740 --> 00:16:01.000 these strange experiments being done down in 00:16:01.000 --> 00:16:03.519 Italy. by Evangelista Torricelli, who was a student 00:16:03.519 --> 00:16:06.120 of Galileo. Torricelli had taken a long glass 00:16:06.120 --> 00:16:08.539 tube, sealed at one end, filled it completely 00:16:08.539 --> 00:16:10.960 with mercury, plugged the open end with his finger, 00:16:11.039 --> 00:16:13.039 and then flipped it upside down into a bowl of 00:16:13.039 --> 00:16:14.899 mercury. And when he took his finger away? The 00:16:14.899 --> 00:16:17.419 column of mercury in the tube fell, but it didn't 00:16:17.419 --> 00:16:19.580 fall all the way. It stopped at a certain height, 00:16:19.659 --> 00:16:23.320 about 30 inches or 760 millimeters. Leaving a 00:16:23.320 --> 00:16:25.240 gap at the top of the tube in the sealed end. 00:16:25.720 --> 00:16:28.340 Exactly, the Torricellian space. And the big 00:16:28.340 --> 00:16:33.149 question was... What is in that space? The Aristotelians 00:16:33.149 --> 00:16:35.669 scrambled for explanations. They said it must 00:16:35.669 --> 00:16:38.350 be filled with mercury vapor or a pocket of that 00:16:38.350 --> 00:16:40.950 invisible ether. Pascal heard about this and 00:16:40.950 --> 00:16:44.169 had a simpler idea. He said, no, it's empty. 00:16:44.169 --> 00:16:47.129 It's a vacuum. It's nothing. And being Pascal, 00:16:47.429 --> 00:16:49.470 he didn't just write a polite paper about it. 00:16:49.490 --> 00:16:52.529 He designed a show. He loved these big, dramatic 00:16:52.529 --> 00:16:55.289 public demonstrations. He was a bit of a showman. 00:16:55.370 --> 00:16:58.049 A total showman. He published a paper called 00:16:58.049 --> 00:17:01.690 New Experiments with the Vacuum in 1647. And 00:17:01.690 --> 00:17:04.009 he repeated Torricelli's experiment, but he did 00:17:04.009 --> 00:17:06.890 these wild variations. He used water and red 00:17:06.890 --> 00:17:09.109 wine instead of mercury. I love the detail about 00:17:09.109 --> 00:17:11.190 the wine. Right. He used different liquids to 00:17:11.190 --> 00:17:13.430 prove it was about density and weight. And because 00:17:13.430 --> 00:17:15.509 water and wine are much lighter than mercury, 00:17:15.819 --> 00:17:18.460 The column stood much, much higher. He had to 00:17:18.460 --> 00:17:21.099 use glass tubes that were 40 feet long and strap 00:17:21.099 --> 00:17:23.380 them to the masts of ships in the middle of a 00:17:23.380 --> 00:17:26.160 courtyard in Rouen. It was a spectacle. But the 00:17:26.160 --> 00:17:28.319 crucial part was his explanation for why the 00:17:28.319 --> 00:17:31.299 liquid stood up in the tube at all. Yes. The 00:17:31.299 --> 00:17:34.099 Old Guard, the Aristotelians, said that the vacuum 00:17:34.099 --> 00:17:36.980 at the top was actively pulling the liquid up, 00:17:37.099 --> 00:17:40.319 a kind of suction force. Pascal suspected the 00:17:40.319 --> 00:17:43.000 exact opposite. He thought it was the immense 00:17:43.000 --> 00:17:45.579 weight of the ocean of air above us pushing down 00:17:45.579 --> 00:17:47.920 on the surface of the liquid in the bowl that 00:17:47.920 --> 00:17:50.200 was forcing it up into the tube. Atmospheric 00:17:50.200 --> 00:17:52.380 pressure, the idea that we are all living at 00:17:52.380 --> 00:17:54.819 the bottom of a deep sea of air. That's the concept. 00:17:54.880 --> 00:17:57.240 And to prove that, he came up with a brilliant 00:17:57.240 --> 00:18:00.309 idea for an experiment. He realized that if air 00:18:00.309 --> 00:18:03.170 has weight, then there must be less air and therefore 00:18:03.170 --> 00:18:05.349 less pressure at the top of a mountain than there 00:18:05.349 --> 00:18:07.750 is at the bottom. This is the PD dome experiment. 00:18:08.009 --> 00:18:11.829 This is the definitive Mike drop moment of 17th 00:18:11.829 --> 00:18:14.579 century physics. Pascal reasoned it all out, 00:18:14.619 --> 00:18:17.000 but there was a problem. He was always sickly. 00:18:17.079 --> 00:18:19.400 He suffered from debilitating stomach pains, 00:18:19.500 --> 00:18:21.900 terrible migraines his whole life. There was 00:18:21.900 --> 00:18:23.920 no way he could hike up a mountain himself. So 00:18:23.920 --> 00:18:26.660 he outsources the work. He does. He writes a 00:18:26.660 --> 00:18:28.619 letter to his brother -in -law, Florent Perrier, 00:18:28.779 --> 00:18:30.759 who conveniently lived near the Prix du Dome, 00:18:30.759 --> 00:18:32.660 which is a large volcanic mountain in central 00:18:32.660 --> 00:18:35.240 France. I can just imagine the letter. Dearest 00:18:35.240 --> 00:18:37.740 Florent... Hope you were well. Would you mind 00:18:37.740 --> 00:18:40.099 doing me a small favor in climbing a nearly 5 00:18:40.099 --> 00:18:43.400 ,000 -foot mountain while carrying a very delicate 00:18:43.400 --> 00:18:47.140 glass tube full of toxic mercury? Thanks, Blaze. 00:18:48.180 --> 00:18:51.259 That's pretty much it. And to his credit, Florin 00:18:51.259 --> 00:18:55.059 did it. On September 19, 1648, Perrier assembled 00:18:55.059 --> 00:18:58.259 a team of local dignitaries, priests, officials, 00:18:58.519 --> 00:19:01.940 doctors to act as official witnesses. He wanted 00:19:01.940 --> 00:19:03.500 to make sure it was all documented properly. 00:19:03.700 --> 00:19:06.640 Oh, yes. This was science as a legal proceeding. 00:19:07.140 --> 00:19:09.859 So first, they set up the barometer in the garden 00:19:09.859 --> 00:19:12.079 of the Minim Fathers Monastery at the base of 00:19:12.079 --> 00:19:14.000 the mountain. They measured the height of the 00:19:14.000 --> 00:19:16.680 mercury column. It stood at 26 French inches 00:19:16.680 --> 00:19:18.740 and three and a half lines. And then they start 00:19:18.740 --> 00:19:21.549 climbing. Then Perrier and his team start the 00:19:21.549 --> 00:19:23.930 3 ,000 -foot ascent to the summit. When they 00:19:23.930 --> 00:19:26.049 get to the top, in the wind, they set up the 00:19:26.049 --> 00:19:27.930 apparatus again. And the result? The mercury 00:19:27.930 --> 00:19:30.150 had dropped. It was significantly lower. It was 00:19:30.150 --> 00:19:32.890 now only 23 inches in two lines, a difference 00:19:32.890 --> 00:19:35.150 of more than three inches. Which is a huge difference. 00:19:35.470 --> 00:19:37.869 It's massive. And to be thorough, they measured 00:19:37.869 --> 00:19:40.210 it at several points on the way back down, and 00:19:40.210 --> 00:19:42.509 the mercury column rose steadily and predictably 00:19:42.509 --> 00:19:44.690 as they descended, returning to its original 00:19:44.690 --> 00:19:47.609 height back in the garden. It was irrefutable. 00:19:47.829 --> 00:19:50.230 The weight of the air was the cause. The suction 00:19:50.230 --> 00:19:53.670 of the vacuum was a myth. It was dead. And Pascal, 00:19:53.890 --> 00:19:56.230 to confirm it, replicated the experiment himself 00:19:56.230 --> 00:19:58.609 on a smaller scale at the top of a church bell 00:19:58.609 --> 00:20:02.029 tower in Paris. This changed everything. It wasn't 00:20:02.029 --> 00:20:03.829 just about how barometers work. It fundamentally 00:20:03.829 --> 00:20:05.890 changed our understanding of the world we live 00:20:05.890 --> 00:20:09.130 in. We aren't in some magical full plenum. We 00:20:09.130 --> 00:20:11.930 are on a rock wrapped in a finite blanket of 00:20:11.930 --> 00:20:14.829 gas that obeys physical laws. And this seems 00:20:14.829 --> 00:20:16.950 to have cemented his idea of what science should 00:20:16.950 --> 00:20:20.170 be. He established a really rigid standard. He 00:20:20.170 --> 00:20:23.130 did. In a famous letter to a critic, a Jesuit 00:20:23.130 --> 00:20:26.369 named Etienne Noel, Pascal basically laid out 00:20:26.369 --> 00:20:29.150 the modern principle of falsifiability 100 years 00:20:29.150 --> 00:20:32.410 before Karl Popper. He said, in effect, your 00:20:32.410 --> 00:20:35.329 theory can explain 99 phenomena perfectly, but 00:20:35.329 --> 00:20:37.769 if one single repeatable fact contradicts it, 00:20:37.829 --> 00:20:40.170 your theory is false, period. It doesn't matter 00:20:40.170 --> 00:20:42.309 what Aristotle said. It doesn't matter what authority 00:20:42.309 --> 00:20:44.130 says. All that matters is what the mercury does 00:20:44.130 --> 00:20:47.069 in the tube. It was a revolution in method. So 00:20:47.069 --> 00:20:50.250 we have the calculator. We have atmospheric pressure 00:20:50.250 --> 00:20:53.009 in the vacuum. Now we're moving into the early 00:20:53.009 --> 00:20:57.569 1650s. His father dies in 1651. Pascal is now 00:20:57.569 --> 00:20:59.869 independently wealthy. He's a bachelor living 00:20:59.869 --> 00:21:02.829 in Paris. And this is what scholars call his 00:21:02.829 --> 00:21:06.230 worldly period. It is. Now, we shouldn't overstate 00:21:06.230 --> 00:21:08.529 it. He wasn't some great debauched libertine. 00:21:09.109 --> 00:21:11.369 But he definitely enjoyed the finer things in 00:21:11.369 --> 00:21:13.650 life for a while. He had a coach and four horses. 00:21:13.710 --> 00:21:16.190 He frequented the fashionable salons. And he 00:21:16.190 --> 00:21:18.730 fell in with a very specific crowd. You know, 00:21:18.769 --> 00:21:21.549 writers, aristocrats, and gamblers. And professional 00:21:21.549 --> 00:21:24.089 gamblers, by their very nature, are obsessed 00:21:24.089 --> 00:21:27.079 with odds and fairness. They have to be. One 00:21:27.079 --> 00:21:29.660 of Pascal's friends was a writer and a man about 00:21:29.660 --> 00:21:31.880 town named the Chevalier de Marais. He was a 00:21:31.880 --> 00:21:34.640 very keen gambler. And de Marais came to Pascal 00:21:34.640 --> 00:21:37.200 with a question that had apparently stumped mathematicians 00:21:37.200 --> 00:21:39.660 for centuries. It's famously known as the problem 00:21:39.660 --> 00:21:42.000 of points. Okay, what's the scenario here? The 00:21:42.000 --> 00:21:44.619 setup is simple. Imagine you and I are playing 00:21:44.619 --> 00:21:47.779 a game of chance. Say, flipping a coin. We've 00:21:47.779 --> 00:21:50.579 each put 50 gold coins into a pot. The first 00:21:50.579 --> 00:21:52.759 person to win five rounds gets the whole hundred 00:21:52.759 --> 00:21:55.579 coin pot. Count it. But for some reason, we have 00:21:55.579 --> 00:21:57.900 to stop the game early. The candles burn out, 00:21:57.960 --> 00:22:00.559 the police raid the gambling den, whatever. And 00:22:00.559 --> 00:22:03.500 when we stop, the score is you have won four 00:22:03.500 --> 00:22:06.579 rounds and I have only won three rounds. So I'm 00:22:06.579 --> 00:22:09.559 ahead. You're ahead. The question is, how do 00:22:09.559 --> 00:22:11.880 we divide the hundred coins in the pot in a way 00:22:11.880 --> 00:22:14.460 that is perfectly mathematically fair? Well, 00:22:14.460 --> 00:22:17.440 the simple answer is just to give it all to me 00:22:17.440 --> 00:22:20.759 since I was winning. Or maybe. Maybe split it 00:22:20.759 --> 00:22:23.099 based on the ratio of our scores, so a 4 to 3 00:22:23.099 --> 00:22:24.759 split. Right, those are the intuitive answers. 00:22:25.180 --> 00:22:27.599 But Desmarais and Pascal knew that neither of 00:22:27.599 --> 00:22:30.079 those is truly fair, because the fair way to 00:22:30.079 --> 00:22:31.920 divide the stakes must depend on the probability 00:22:31.920 --> 00:22:34.259 of what would have happened if the game had continued. 00:22:34.519 --> 00:22:37.039 Ah, so you're not looking at the past, at the 00:22:37.039 --> 00:22:39.480 scores we already have. You're modeling the future. 00:22:39.960 --> 00:22:43.140 That is the crucial revolutionary leap. They 00:22:43.140 --> 00:22:46.660 are trying to quantify the future. So Pascal... 00:22:46.839 --> 00:22:49.519 Intrigued by this, starts a correspondence with 00:22:49.519 --> 00:22:52.640 another one of the great minds of the era, Pierre 00:22:52.640 --> 00:22:54.640 de Fermat. Who was another one of these brilliant 00:22:54.640 --> 00:22:57.220 amateurs. He was a lawyer by trade. A lawyer 00:22:57.220 --> 00:22:59.859 in Toulouse. And in a series of letters back 00:22:59.859 --> 00:23:03.039 and forth in the summer of 1654, these two men, 00:23:03.240 --> 00:23:06.440 Pascal and Fermat, solved it. They realized you 00:23:06.440 --> 00:23:09.240 have to map out all the possible future outcomes. 00:23:09.380 --> 00:23:12.750 So in our game. If we play one more round. There's 00:23:12.750 --> 00:23:14.950 a 50 % chance you win and the game is over. You 00:23:14.950 --> 00:23:16.809 take the pot. Okay. And there's a 50 % chance 00:23:16.809 --> 00:23:18.809 that I win, in which case the score becomes tied 00:23:18.809 --> 00:23:21.569 four to four. Then we'd have to play a final 00:23:21.569 --> 00:23:24.509 deciding round. By mapping out this tree of possibilities 00:23:24.509 --> 00:23:26.890 and weighing each branch by its probability, 00:23:27.269 --> 00:23:29.329 they calculated what they called the expected 00:23:29.329 --> 00:23:31.769 value for each player. And this is it. This is 00:23:31.769 --> 00:23:34.789 the birth of modern probability theory. This 00:23:34.789 --> 00:23:38.259 is the moment. Before this, the future was seen 00:23:38.259 --> 00:23:42.119 as the domain of God or fate or just pure blind 00:23:42.119 --> 00:23:45.900 luck. It was fundamentally unknowable. Pascal 00:23:45.900 --> 00:23:48.019 and Fermat proved that while you can't predict 00:23:48.019 --> 00:23:50.480 the specific outcome of a single future event, 00:23:50.740 --> 00:23:53.359 you can absolutely predict the pattern of outcomes 00:23:53.359 --> 00:23:56.099 over the long run. You can tame uncertainty. 00:23:56.299 --> 00:23:59.319 This underpins, I mean, everything in our modern 00:23:59.319 --> 00:24:02.099 world. Insurance markets, stock market analysis, 00:24:02.440 --> 00:24:05.259 medical trials, election polling, quantum mechanics. 00:24:05.500 --> 00:24:07.980 It all starts right here with two French guys 00:24:07.980 --> 00:24:09.980 trying to figure out the fair way to split a 00:24:09.980 --> 00:24:11.920 gambling pot. And in the middle of all this work, 00:24:12.119 --> 00:24:15.160 Pascal decides to synthesize a lot of his thinking 00:24:15.160 --> 00:24:17.839 about numbers into his treatise on the arithmetical 00:24:17.839 --> 00:24:19.859 triangle. Right. What we all learn in school 00:24:19.859 --> 00:24:22.640 as Pascal's triangle. That pyramid of numbers 00:24:22.640 --> 00:24:25.380 we've all seen where each number is the sum of 00:24:25.380 --> 00:24:27.339 the two numbers directly above it. Now, to be 00:24:27.339 --> 00:24:29.180 clear, he didn't invent the triangle itself. 00:24:29.460 --> 00:24:31.880 The pattern was known to mathematicians in China, 00:24:31.980 --> 00:24:35.039 Persia, and India for centuries before him. But 00:24:35.039 --> 00:24:37.380 Pascal was the first person to really explore 00:24:37.380 --> 00:24:39.819 all of its properties systematically and write 00:24:39.819 --> 00:24:42.039 them down. And he showed how it connected to 00:24:42.039 --> 00:24:44.680 probability. He did. He showed that the numbers 00:24:44.680 --> 00:24:47.799 in the rows are the binomial coefficients. So 00:24:47.799 --> 00:24:49.700 if you want to know, say, how many different 00:24:49.700 --> 00:24:52.019 ways can you choose a committee of three people 00:24:52.019 --> 00:24:54.400 from a group of five, you just go to the fifth 00:24:54.400 --> 00:24:56.279 row of the triangle and the third number is... 00:24:56.269 --> 00:24:58.890 and there's your answer. It's a beautiful, elegant 00:24:58.890 --> 00:25:01.369 tool. There's one more little mathematical story 00:25:01.369 --> 00:25:05.210 from this period involving a toothache. The cycloid. 00:25:05.329 --> 00:25:08.210 Yes, though this happens a bit later in 1658 00:25:08.210 --> 00:25:11.009 after his major religious conversion. But it 00:25:11.009 --> 00:25:13.190 shows his mind was still working on these problems. 00:25:13.430 --> 00:25:16.009 He was suffering from a terrible, raging toothache 00:25:16.009 --> 00:25:18.329 that kept him awake all night. And just as a 00:25:18.329 --> 00:25:20.250 way to distract himself from the pain. A very 00:25:20.250 --> 00:25:22.670 Pascal thing to do. Very. He started thinking 00:25:22.670 --> 00:25:25.049 about a famous unsolved problem in geometry. 00:25:25.789 --> 00:25:28.789 The cycloid. That's the curve traced by a point 00:25:28.789 --> 00:25:31.269 on the rim of a rolling wheel. He used geometry 00:25:31.269 --> 00:25:34.349 as a painkiller. And it worked. As he got deeper 00:25:34.349 --> 00:25:37.390 into the problem, the pain vanished. And he took 00:25:37.390 --> 00:25:40.289 this as a divine signal, a sign from God that 00:25:40.289 --> 00:25:41.970 it was okay for him to engage in mathematics 00:25:41.970 --> 00:25:44.769 as long as it wasn't for vanity. So he solves 00:25:44.769 --> 00:25:47.779 it. He solves it in eight days. He figures out 00:25:47.779 --> 00:25:50.279 the area under the curve, the volume of the shape 00:25:50.279 --> 00:25:52.720 it creates when rotated problems that had stumped 00:25:52.720 --> 00:25:55.680 giants like Galileo and Torricelli. And then, 00:25:55.720 --> 00:25:58.900 in a very strange move, he held a contest under 00:25:58.900 --> 00:26:01.740 a pseudonym, challenging the other great mathematicians 00:26:01.740 --> 00:26:04.279 of Europe to solve it. And then he declared himself 00:26:04.279 --> 00:26:06.740 the winner of his own contest. It did. It was 00:26:06.740 --> 00:26:09.599 a little controversial. Great minds like Christopher 00:26:09.599 --> 00:26:12.660 Wren and John Wallace submitted solutions, but 00:26:12.660 --> 00:26:15.509 Pascal writing as Amos... Dettenville, judged 00:26:15.509 --> 00:26:18.309 his own anonymous solution to be the only fully 00:26:18.309 --> 00:26:21.269 correct one. It just shows that even as he was 00:26:21.269 --> 00:26:24.210 becoming more religious, he still had that incredibly 00:26:24.210 --> 00:26:27.890 sharp, competitive, almost arrogant edge to him. 00:26:28.029 --> 00:26:30.190 Absolutely. But that competitive edge was about 00:26:30.190 --> 00:26:32.309 to be redirected toward a very, very different 00:26:32.309 --> 00:26:34.730 kind of opponent. We have to talk about the great 00:26:34.730 --> 00:26:37.109 shift, the event that changed his life forever, 00:26:37.369 --> 00:26:40.220 the Night of Fire. Because for all his worldly 00:26:40.220 --> 00:26:42.980 success, all the fame from his math and physics, 00:26:43.400 --> 00:26:46.299 Pascal was deeply unhappy. He described it as 00:26:46.299 --> 00:26:49.160 a period of profound spiritual dryness, even 00:26:49.160 --> 00:26:52.619 disgust. He had the money. He had the fame. He 00:26:52.619 --> 00:26:55.160 was celebrated in the salons. But he felt this 00:26:55.160 --> 00:26:58.170 deep sense of his own wretchedness. And at the 00:26:58.170 --> 00:27:00.910 same time, his younger sister Jacqueline, whom 00:27:00.910 --> 00:27:04.029 he was very close to, had become a nun at the 00:27:04.029 --> 00:27:06.670 Port Royal Abbey. And Port Royal was the absolute 00:27:06.670 --> 00:27:09.029 center of a controversial religious movement 00:27:09.029 --> 00:27:12.089 called Jansenism. We really need to define Jansenism 00:27:12.089 --> 00:27:14.529 because it is the essential backdrop for the 00:27:14.529 --> 00:27:17.250 entire second half of Pascal's life. So what 00:27:17.250 --> 00:27:20.279 was it? You can think of Jansenism as a very 00:27:20.279 --> 00:27:23.660 rigorous, very austere reformist wing within 00:27:23.660 --> 00:27:25.940 the Catholic Church. They were heavily influenced 00:27:25.940 --> 00:27:28.480 by the writings of St. Augustine. They believed 00:27:28.480 --> 00:27:31.019 that human nature was totally and utterly corrupted 00:27:31.019 --> 00:27:33.180 after the fall of man in the Garden of Eden. 00:27:33.339 --> 00:27:35.779 So we're inherently broken. Utterly broken. We 00:27:35.779 --> 00:27:38.380 are incapable of doing any good on our own. We 00:27:38.380 --> 00:27:40.759 can only be saved by God's grace, and that grace 00:27:40.759 --> 00:27:43.200 is irresistible, but it is given only to a select 00:27:43.200 --> 00:27:46.019 few. the elect. You can't earn it. You can't 00:27:46.019 --> 00:27:47.900 work your way to heaven. It sounds a lot like 00:27:47.900 --> 00:27:50.200 Calvinism, but inside the Catholic Church. It 00:27:50.200 --> 00:27:53.160 is very, very similar in its theology to Calvinist 00:27:53.160 --> 00:27:55.160 predestination. And that, as you can imagine, 00:27:55.220 --> 00:27:57.099 got them into a huge amount of trouble with the 00:27:57.099 --> 00:27:59.619 mainstream church, especially with the Pope and 00:27:59.619 --> 00:28:02.779 the powerful Jesuit order. But for Pascal, this 00:28:02.779 --> 00:28:05.539 rigorous, all or nothing, uncompromising view 00:28:05.539 --> 00:28:08.220 of the world. It resonated with his personality. 00:28:08.599 --> 00:28:11.339 He was a man of absolutes. So this is all swirling 00:28:11.339 --> 00:28:14.059 in his mind. And then we come to the night of 00:28:14.059 --> 00:28:19.500 November 23, 1654. Pascal is 31 years old. He's 00:28:19.500 --> 00:28:21.180 at his home in Paris. It's late at night. And 00:28:21.180 --> 00:28:24.839 from about 10 .30 p .m. to 12 .30 a .m. for two 00:28:24.839 --> 00:28:27.880 solid hours, he undergoes some kind of intense, 00:28:28.099 --> 00:28:30.720 direct, mystical experience. We don't really 00:28:30.720 --> 00:28:32.319 know what happened. We don't. He never spoke 00:28:32.319 --> 00:28:34.440 about the details to anyone verbally, but we 00:28:34.440 --> 00:28:36.180 know he grabbed a piece of parchment and in a 00:28:36.180 --> 00:28:39.000 frantic, ecstatic state, he scrawled down a series 00:28:39.000 --> 00:28:41.299 of short, fiery phrases to capture the moment. 00:28:41.460 --> 00:28:43.259 And this is the document that we now call the 00:28:43.259 --> 00:28:45.700 memorial. Yes. And it starts with the single 00:28:45.700 --> 00:28:48.259 word FIRE written in huge capital letters at 00:28:48.259 --> 00:28:50.130 the top. And then it says God of Abraham, God 00:28:50.130 --> 00:28:52.809 of Isaac, God of Jacob, not of the philosophers 00:28:52.809 --> 00:28:55.869 and the scholars. Wow. Not of the philosophers 00:28:55.869 --> 00:28:58.349 and the scholars. That is a direct rejection 00:28:58.349 --> 00:29:00.890 of his entire life up to that point. Yeah. He's 00:29:00.890 --> 00:29:03.130 saying the abstract geometric God of Descartes, 00:29:03.150 --> 00:29:06.549 the prime mover. That's not the real God. Not 00:29:06.549 --> 00:29:09.430 at all. He goes on. He writes certitude, certitude, 00:29:09.430 --> 00:29:13.390 feeling, joy, peace, and then joy, joy, joy, 00:29:13.609 --> 00:29:16.859 tears of joy. This wasn't an intellectual conclusion. 00:29:17.039 --> 00:29:19.500 This was a visceral, emotional, overwhelming 00:29:19.500 --> 00:29:22.180 encounter with a personal deity. And what he 00:29:22.180 --> 00:29:24.119 did with this piece of paper is to me the most 00:29:24.119 --> 00:29:26.319 telling part of the whole story. He didn't frame 00:29:26.319 --> 00:29:29.059 it on his wall. No, he folded it up and he sewed 00:29:29.059 --> 00:29:31.039 it into the lining of his coat right over his 00:29:31.039 --> 00:29:32.819 heart. And for the rest of his life, whenever 00:29:32.819 --> 00:29:35.119 he got a new coat, he would carefully unpick 00:29:35.119 --> 00:29:37.180 the seam, take out the precious parchment and 00:29:37.180 --> 00:29:39.339 sew it into the new one. He literally kept that 00:29:39.339 --> 00:29:41.700 fire close to his heart every single day. A servant 00:29:41.700 --> 00:29:44.259 only discovered it by chance after he died. That 00:29:44.259 --> 00:29:46.519 moment really marks the death of Pascal the scientist 00:29:46.519 --> 00:29:48.640 and the birth of Pascal the religious apologist. 00:29:49.059 --> 00:29:51.359 He effectively retires from math and science 00:29:51.359 --> 00:29:53.599 and goes to live in seclusion at Port Royal. 00:29:54.650 --> 00:29:57.309 Almost immediately, he gets drafted into a war, 00:29:57.450 --> 00:30:00.609 a theological war. The Jansenists were under 00:30:00.609 --> 00:30:03.430 fierce attack from the Jesuits. The Sorbonne 00:30:03.430 --> 00:30:05.849 in Paris was trying to formally censure a leading 00:30:05.849 --> 00:30:09.309 Jansenist theologian, Antoine Arnaud. The Jansenists 00:30:09.309 --> 00:30:11.089 were losing the public relations battle. They 00:30:11.089 --> 00:30:13.269 needed a champion. They needed someone who could 00:30:13.269 --> 00:30:15.690 write. So they capped the new guy. They tapped 00:30:15.690 --> 00:30:18.460 Pascal. And he produces the provincial letters. 00:30:18.640 --> 00:30:21.200 Which are 18 letters written under the brilliant 00:30:21.200 --> 00:30:24.680 pseudonym Louis de Montelt, supposedly a symbol 00:30:24.680 --> 00:30:26.960 man from Paris writing to his friend back in 00:30:26.960 --> 00:30:30.059 the provinces. And they are an absolute masterpiece 00:30:30.059 --> 00:30:32.700 of satire and polemic. And he's attacking the 00:30:32.700 --> 00:30:35.000 Jesuit method of moral reasoning, which he calls 00:30:35.000 --> 00:30:37.650 casuistry. Casuistry. It sounds like casual, 00:30:37.710 --> 00:30:40.569 but it's much more complex. Casuistry is case 00:30:40.569 --> 00:30:43.190 based ethical reasoning. The Jesuits developed 00:30:43.190 --> 00:30:45.430 it as a way to help people navigate complex moral 00:30:45.430 --> 00:30:47.869 situations in confession. So on the surface, 00:30:47.950 --> 00:30:51.269 it sounds helpful. It can be. But Pascal argued 00:30:51.269 --> 00:30:54.269 viciously and brilliantly that the Jesuits were 00:30:54.269 --> 00:30:57.289 abusing it. They were using hyper complex hair 00:30:57.289 --> 00:31:00.150 splitting logic to create loopholes that could 00:31:00.150 --> 00:31:03.910 justify almost any sin. He accused them of being 00:31:03.910 --> 00:31:06.509 slimy moral lawyers who could get you off the 00:31:06.509 --> 00:31:09.130 hook for murder or theft if you just defined 00:31:09.130 --> 00:31:11.630 your intention in the right way. Can you give 00:31:11.630 --> 00:31:14.769 us an example of the kind of Jesuitical logic 00:31:14.769 --> 00:31:17.170 he was mocking? Oh, absolutely. He has a field 00:31:17.170 --> 00:31:20.210 day with it. He mocks the idea that while killing 00:31:20.210 --> 00:31:23.109 someone in a formal duel is a mortal sin, you 00:31:23.109 --> 00:31:25.630 can get around it by, say, simply going for a 00:31:25.630 --> 00:31:27.369 walk in a field where you happen to know your 00:31:27.369 --> 00:31:29.549 enemy is waiting. And then if he attacks you, 00:31:29.609 --> 00:31:31.529 well, you can kill him in self -defense. It's 00:31:31.529 --> 00:31:34.170 all about plausible deniability. Exactly. And 00:31:34.170 --> 00:31:37.329 he just shreds this kind of tortured logic. But 00:31:37.329 --> 00:31:39.210 the genius of the letters is that he does it 00:31:39.210 --> 00:31:41.900 with humor. They are genuinely funny. They're 00:31:41.900 --> 00:31:44.380 witty. They're conversational. They're not dense 00:31:44.380 --> 00:31:46.099 theological tracks. And this is where we get 00:31:46.099 --> 00:31:48.160 that famous quote about brevity, isn't it? It 00:31:48.160 --> 00:31:50.779 is. In the 16th letter, he apologizes to his 00:31:50.779 --> 00:31:52.880 correspondent, writing, I have made this longer 00:31:52.880 --> 00:31:54.660 than usual because I have not had time to make 00:31:54.660 --> 00:31:57.380 it shorter. And that captures his style perfectly 00:31:57.380 --> 00:32:00.819 lucid, precise, devastatingly efficient. And 00:32:00.819 --> 00:32:03.190 these letters became a sensation. They were illegal, 00:32:03.390 --> 00:32:05.609 but they were passed around secretly. A black 00:32:05.609 --> 00:32:08.529 market bestseller. The king tried to ban them 00:32:08.529 --> 00:32:10.829 and have them burned. But everybody in Paris 00:32:10.829 --> 00:32:13.329 from the intellectuals to the shopkeepers was 00:32:13.329 --> 00:32:15.990 reading them. They completely changed French 00:32:15.990 --> 00:32:19.190 prose. Before Pascal, serious Frank writing was 00:32:19.190 --> 00:32:22.230 often flowery and dense. Pascal wrote with the 00:32:22.230 --> 00:32:24.289 clarity of a geometric proof, but the wit of 00:32:24.289 --> 00:32:27.190 a stand -up comedian. Later giants like Voltaire 00:32:27.190 --> 00:32:29.789 and Rousseau both pointed to the provincial letters 00:32:29.789 --> 00:32:33.009 as the birth of modern French prose. So he successfully 00:32:33.009 --> 00:32:35.829 defends his friends. He publicly humiliates the 00:32:35.829 --> 00:32:38.450 Jesuits. But he has a much bigger, more ambitious 00:32:38.450 --> 00:32:41.809 project in mind. He wants to write a full, comprehensive 00:32:41.809 --> 00:32:44.559 defense of the Christian religion. An apology. 00:32:44.819 --> 00:32:47.579 This is the great unfinished work of his life. 00:32:47.819 --> 00:32:50.019 And it's what eventually became the book we know 00:32:50.019 --> 00:32:52.700 today as the Pensée, which just means thoughts. 00:32:52.920 --> 00:32:55.140 He never finished it. He died leaving behind 00:32:55.140 --> 00:32:57.940 just hundreds of notes and fragments, some meticulously 00:32:57.940 --> 00:33:00.000 organized and tied into bundles with string, 00:33:00.220 --> 00:33:03.500 others just random phrases jotted on scraps of 00:33:03.500 --> 00:33:06.180 paper. So later editors had to piece it all together 00:33:06.180 --> 00:33:08.980 like a puzzle. Exactly. Which is why it can be 00:33:08.980 --> 00:33:11.559 a challenging read. But even as fragments, they 00:33:11.559 --> 00:33:14.069 are just devastatingly powerful. He focuses so 00:33:14.069 --> 00:33:16.450 intently on the contradictions of the human condition. 00:33:16.630 --> 00:33:19.490 He does. He paints this terrifying picture of 00:33:19.490 --> 00:33:21.890 humanity suspended between two infinities, two 00:33:21.890 --> 00:33:25.089 abysses. On one side, you have the abyss of the 00:33:25.089 --> 00:33:27.789 infinitely large, the silent, terrifying universe 00:33:27.789 --> 00:33:30.289 of stars and galaxies that is too big for us 00:33:30.289 --> 00:33:33.069 to comprehend. And on the other, the abyss of 00:33:33.069 --> 00:33:35.349 the infinitely small, the world of mites and 00:33:35.349 --> 00:33:37.650 atoms that we can't see. We're trapped in the 00:33:37.650 --> 00:33:40.210 middle, he says, unable to grasp either extreme. 00:33:40.490 --> 00:33:42.670 Which leads to his most famous metaphor for humanity. 00:33:43.369 --> 00:33:46.670 The thinking reed. Man is only a reed, the weakest 00:33:46.670 --> 00:33:49.690 in nature, but he is a thinking reed. It's such 00:33:49.690 --> 00:33:52.450 a perfect image. He fully acknowledges our physical 00:33:52.450 --> 00:33:56.150 fragility. A vapor, a drop of water. The universe 00:33:56.150 --> 00:33:57.970 doesn't have to arm itself to crush us. It's 00:33:57.970 --> 00:34:00.990 easy. Right. But our dignity, our greatness lies 00:34:00.990 --> 00:34:03.839 entirely in our thought. We know that we are 00:34:03.839 --> 00:34:06.960 dying. We know the universe is crushing us. The 00:34:06.960 --> 00:34:09.579 universe, he says, knows nothing of this. That 00:34:09.579 --> 00:34:11.940 consciousness, that awareness of our own wretchedness 00:34:11.940 --> 00:34:14.440 is what elevates us. And it's from this analysis 00:34:14.440 --> 00:34:17.039 of the human condition, the state of being lost, 00:34:17.159 --> 00:34:20.400 confused, and self -aware, that he produces the 00:34:20.400 --> 00:34:22.360 most famous and certainly the most controversial 00:34:22.360 --> 00:34:25.900 part of the Pensees. The wager. Pascal's wager, 00:34:25.940 --> 00:34:28.059 yes. And it's so often misunderstood. People 00:34:28.059 --> 00:34:30.260 think it's supposed to be a logical proof of 00:34:30.260 --> 00:34:32.360 God's existence. It's not. He didn't think you 00:34:32.360 --> 00:34:34.940 could prove God with reason. He explicitly believed 00:34:34.940 --> 00:34:36.639 you couldn't. He thought the distance between 00:34:36.639 --> 00:34:39.599 our finite minds and an infinite God was, well, 00:34:39.679 --> 00:34:42.800 infinite. Reason is powerless. So he reframes 00:34:42.800 --> 00:34:45.000 the question. This is not a logic problem. It's 00:34:45.000 --> 00:34:48.079 a decision problem. A gamble. He brings the gambler 00:34:48.079 --> 00:34:50.059 from his worldly period back into his theology. 00:34:50.559 --> 00:34:53.179 He absolutely does. He imagines he's talking 00:34:53.179 --> 00:34:55.559 to a skeptic, a friend from the salons, who says, 00:34:55.739 --> 00:34:58.179 I just don't know if God exists or not, so I'm 00:34:58.179 --> 00:35:00.159 not going to choose. I will suspend judgment. 00:35:00.239 --> 00:35:02.739 I won't bet. Which seems like a reasonable position. 00:35:03.019 --> 00:35:06.260 It does. But Pascal's brilliant move is to say, 00:35:06.280 --> 00:35:08.400 you can't suspend judgment. You have no choice. 00:35:08.679 --> 00:35:11.579 You are already embarked. You are alive. Your 00:35:11.579 --> 00:35:13.619 life is moving forward toward death. You are 00:35:13.619 --> 00:35:17.159 already in the game. You must place a bet. So 00:35:17.159 --> 00:35:19.219 he draws up the betting matrix. Let's walk through 00:35:19.219 --> 00:35:21.880 the four quadrants of the wager. Okay. Quadrant 00:35:21.880 --> 00:35:24.920 one. You choose to bet that God exists, and it 00:35:24.920 --> 00:35:26.639 turns out you're right. He does exist. What's 00:35:26.639 --> 00:35:29.449 the result? Infinite gain. Eternal happiness, 00:35:29.730 --> 00:35:33.030 heaven. Okay. Quadrant two, you bet God exists 00:35:33.030 --> 00:35:35.349 and it turns out you're wrong. He doesn't. What 00:35:35.349 --> 00:35:38.250 did you lose? A finite loss. You lived a virtuous 00:35:38.250 --> 00:35:40.349 life. Maybe you missed out on some parties or 00:35:40.349 --> 00:35:42.730 pleasures. Then you died and that was it. You 00:35:42.730 --> 00:35:45.449 lost a few earthly experiences. Right. A limited 00:35:45.449 --> 00:35:48.590 finite loss. Now, the other side. Quadrant three, 00:35:48.710 --> 00:35:51.449 you bet that God does not exist and you're wrong. 00:35:51.570 --> 00:35:55.210 He does exist. Infinite loss. Damnation. Losing 00:35:55.210 --> 00:35:57.420 out on everything that matter. The ultimate bad 00:35:57.420 --> 00:36:00.800 outcome. And finally, quadrant four. You bet 00:36:00.800 --> 00:36:03.760 God doesn't exist. And you're right. A finite 00:36:03.760 --> 00:36:06.280 gain. You enjoyed those parties you otherwise 00:36:06.280 --> 00:36:08.860 would have missed. You died. And that was it. 00:36:09.210 --> 00:36:11.750 So when you lay it out like that, it becomes 00:36:11.750 --> 00:36:14.150 a problem of probability and expected value, 00:36:14.349 --> 00:36:17.090 just like the problem of points. You have a choice 00:36:17.090 --> 00:36:19.889 between a finite risk for a potentially infinite 00:36:19.889 --> 00:36:22.809 reward on one side and a finite reward for a 00:36:22.809 --> 00:36:25.489 potentially infinite risk on the other. And Pascal's 00:36:25.489 --> 00:36:28.769 conclusion is that no rational gambler, no sane 00:36:28.769 --> 00:36:32.719 person would ever bet against the infinite. Even 00:36:32.719 --> 00:36:34.519 if you think the probability of God existing 00:36:34.519 --> 00:36:38.199 is tiny, one in a billion, the potential infinite 00:36:38.199 --> 00:36:40.840 payoff still makes it the only rational bet. 00:36:41.000 --> 00:36:43.480 The expected value of believing is always infinite. 00:36:43.639 --> 00:36:46.300 That's the cold, hard logic of it. But people, 00:36:46.400 --> 00:36:48.239 and I include myself here, people have always 00:36:48.239 --> 00:36:50.400 had a problem with this argument. It feels cold. 00:36:50.579 --> 00:36:53.840 It feels cynical, mercenary. It feels transactional. 00:36:53.900 --> 00:36:56.480 I'll believe just in case to cover my bet. Right. 00:36:56.559 --> 00:36:58.059 And it feels like you're just faking it. You 00:36:58.059 --> 00:36:59.860 can't just decide to believe something because 00:36:59.860 --> 00:37:03.199 it's a good bet. And Pascal, brilliant psychologist 00:37:03.199 --> 00:37:05.639 that he was, anticipated this objection completely. 00:37:05.840 --> 00:37:08.500 He has his skeptics say, OK, I'm convinced by 00:37:08.500 --> 00:37:10.599 the logic, but I can't make myself believe. What 00:37:10.599 --> 00:37:13.880 do I do? And Pascal's advice is chillingly practical. 00:37:14.260 --> 00:37:17.260 He says, if you want to believe but can't, you 00:37:17.260 --> 00:37:19.519 must cure yourself of your passions, which are 00:37:19.519 --> 00:37:22.119 the obstacle. Start acting as if you believe. 00:37:22.320 --> 00:37:25.139 Go through the motions. Yes. Go to mass. Take 00:37:25.139 --> 00:37:27.900 the holy water. Mumble the prayers, he calls 00:37:27.900 --> 00:37:31.039 it a betir, which literally means to stupefy 00:37:31.039 --> 00:37:33.199 yourself or to make yourself like a beast, like 00:37:33.199 --> 00:37:36.219 the unthinking faithful peasants. He argues that 00:37:36.219 --> 00:37:38.400 by taming your skeptical intellect through habit 00:37:38.400 --> 00:37:41.320 and ritual, genuine faith might eventually follow. 00:37:41.500 --> 00:37:43.420 It's fake it till you make it, applied to the 00:37:43.420 --> 00:37:45.750 salvation of your soul. It's a profound psychological 00:37:45.750 --> 00:37:48.469 insight. He understood, perhaps better than anyone, 00:37:48.630 --> 00:37:51.030 that belief isn't always a purely intellectual 00:37:51.030 --> 00:37:53.309 switch you can flip. It's a habit of the heart, 00:37:53.389 --> 00:37:56.150 and habits are formed through action. So we are 00:37:56.150 --> 00:37:58.349 nearing the end of his short life now. He is 00:37:58.349 --> 00:38:00.369 wracked with illness. He's coring his soul into 00:38:00.369 --> 00:38:03.030 these fragmented thoughts. But he has one last 00:38:03.030 --> 00:38:07.769 surprising invention left in him. In 1662, the 00:38:07.769 --> 00:38:10.829 very year he dies, he decides to fix the traffic 00:38:10.829 --> 00:38:14.099 problem in Paris. It's just the most wonderful 00:38:14.099 --> 00:38:18.099 and unexpected final act. The Carassas à Saint 00:38:18.099 --> 00:38:20.960 -Saëns, the five sole carriages. Pascal looked 00:38:20.960 --> 00:38:22.880 at the city of Paris and he saw a problem of 00:38:22.880 --> 00:38:25.860 logistics and social equity. If you were poor, 00:38:26.019 --> 00:38:28.480 you walked everywhere. If you were rich, you 00:38:28.480 --> 00:38:30.699 had a private carriage. There was no middle ground. 00:38:30.880 --> 00:38:33.340 So he invents the public bus system. He basically 00:38:33.340 --> 00:38:35.280 does. He, along with some powerful friends like 00:38:35.280 --> 00:38:37.320 the Duke of Rennes, formed a company. They got 00:38:37.320 --> 00:38:40.159 a royal patent. He designed a system of large 00:38:40.159 --> 00:38:42.659 multi passenger carriages that would run on fixed 00:38:42.659 --> 00:38:45.199 rides across Paris for a fixed price of five 00:38:45.199 --> 00:38:47.579 souls. But the truly revolutionary part, the 00:38:47.579 --> 00:38:50.079 part that makes it modern was. the schedule. 00:38:50.199 --> 00:38:53.079 That was the genius of it. The carriages left 00:38:53.079 --> 00:38:55.739 at specific regular times, regardless of whether 00:38:55.739 --> 00:38:57.719 they were full or empty. Which is the single 00:38:57.719 --> 00:39:00.300 defining feature of true public transit, reliability. 00:39:00.760 --> 00:39:03.199 You know the bus will be there. It was an instant 00:39:03.199 --> 00:39:06.039 success. The first line opened in March of 1662. 00:39:06.380 --> 00:39:08.480 There were crowds in the streets cheering for 00:39:08.480 --> 00:39:11.639 it. It was a sensation. Pascal had even stipulated 00:39:11.639 --> 00:39:14.019 in the plans that the profits should go to the 00:39:14.019 --> 00:39:16.639 poor and that the poor must be allowed to ride. 00:39:17.119 --> 00:39:19.300 It just goes to show that his mind never, ever 00:39:19.300 --> 00:39:21.519 turned off. Whether it was the abstract geometry 00:39:21.519 --> 00:39:24.500 of a hexagon or the practical logistics of moving 00:39:24.500 --> 00:39:27.400 people across a city, he saw systems and he wanted 00:39:27.400 --> 00:39:30.059 to optimize them. But he didn't live to see his 00:39:30.059 --> 00:39:33.469 bus line flourish. By the summer of 1662, his 00:39:33.469 --> 00:39:35.969 health had completely collapsed. He was in constant 00:39:35.969 --> 00:39:38.150 agony. Do we know what was actually wrong with 00:39:38.150 --> 00:39:40.730 him physically? It's very difficult to diagnose 00:39:40.730 --> 00:39:43.489 retrospectively from 400 years away. But the 00:39:43.489 --> 00:39:45.690 consensus is that it was likely a combination 00:39:45.690 --> 00:39:48.849 of stomach cancer and malignant tuberculosis. 00:39:48.949 --> 00:39:52.030 He had terrible stomach ulcers. The autopsy that 00:39:52.030 --> 00:39:54.510 was performed revealed grave damage to his stomach, 00:39:54.670 --> 00:39:56.989 his liver, and they even found lesions on his 00:39:56.989 --> 00:39:59.550 brain. And yet in those agonizing final months, 00:39:59.710 --> 00:40:04.440 his religious is set. It did. He sold his fine 00:40:04.440 --> 00:40:06.300 furniture and his carriage to give the money 00:40:06.300 --> 00:40:09.139 to the poor. He had moved into his sister's house, 00:40:09.260 --> 00:40:11.940 but he begged her to let him be taken to a hospital 00:40:11.940 --> 00:40:14.800 for the incurables so that he could die among 00:40:14.800 --> 00:40:19.219 the poorest of the poor. They refused. He was 00:40:19.219 --> 00:40:22.110 simply too sick and unstable to be moved. He 00:40:22.110 --> 00:40:24.110 spent his final days in and out of consciousness, 00:40:24.329 --> 00:40:26.530 suffering from terrible convulsions and pain. 00:40:26.769 --> 00:40:29.590 He made his last confession, he received communion, 00:40:29.849 --> 00:40:32.889 and his last recorded words were, May God never 00:40:32.889 --> 00:40:37.130 abandon me. He died on August 19, 1662. Gone 00:40:37.130 --> 00:40:41.349 at 39. 39. The legacy he leaves behind is, well, 00:40:41.389 --> 00:40:44.269 it's fragmented, just like his pensées. It's 00:40:44.269 --> 00:40:47.369 everywhere. We use the Pascal as the SI unit 00:40:47.369 --> 00:40:49.650 of pressure. There's a major programming language 00:40:49.650 --> 00:40:52.280 named Pascal. Computer chip architectures are 00:40:52.280 --> 00:40:54.739 named after him. And we use his probability theory 00:40:54.739 --> 00:40:56.820 every single time we check a weather forecast 00:40:56.820 --> 00:40:59.659 or read a political poll. And we use his arguments 00:40:59.659 --> 00:41:01.960 or argue against them every time we debate the 00:41:01.960 --> 00:41:04.860 existence of God. And in a deeper sense, we still 00:41:04.860 --> 00:41:06.960 struggle with the same core problems he did. 00:41:07.559 --> 00:41:10.719 We're all still thinking reeds, aware of our 00:41:10.719 --> 00:41:13.579 own mortality, often terrified by the silent, 00:41:13.679 --> 00:41:16.360 infinite spaces of the universe, distracting 00:41:16.360 --> 00:41:18.659 ourselves with our own modern versions of gambling 00:41:18.659 --> 00:41:21.190 and bus schedules. That's the enduring power 00:41:21.190 --> 00:41:24.090 of Pascal. He seems to have seen the modern condition, 00:41:24.449 --> 00:41:27.190 our condition, before modernity had even properly 00:41:27.190 --> 00:41:29.889 begun. He saw that science would give us immense 00:41:29.889 --> 00:41:32.789 power, but it wouldn't and couldn't give us peace. 00:41:33.110 --> 00:41:35.070 I think I want to end with that famous thought 00:41:35.070 --> 00:41:37.869 of his. He wrote, all of humanity's problems 00:41:37.869 --> 00:41:40.670 stem from man's inability to sit quietly in a 00:41:40.670 --> 00:41:44.610 room alone. Divertissement. the constant need 00:41:44.610 --> 00:41:47.269 to be doing something, to be entertained, so 00:41:47.269 --> 00:41:48.929 that we don't have to face the big questions, 00:41:48.989 --> 00:41:51.289 to face ourselves. So a final thought for all 00:41:51.289 --> 00:41:53.610 of you listening. Maybe after this is over, just 00:41:53.610 --> 00:41:55.949 for a few minutes, turn everything off, sit in 00:41:55.949 --> 00:41:59.469 a room, be quiet, and see what happens. It might 00:41:59.469 --> 00:42:01.429 be the hardest experiment Pascal ever proposed. 00:42:01.809 --> 00:42:03.489 Thank you for joining us for this deep dive. 00:42:03.630 --> 00:42:04.329 We'll see you next time.