WEBVTT 00:00:00.000 --> 00:00:03.740 Imagine making a mathematical error at your job, 00:00:04.299 --> 00:00:06.419 and your boss comes up to you and tells you that 00:00:06.419 --> 00:00:09.980 if you don't find a way to fix it, you are going 00:00:09.980 --> 00:00:12.300 to be crucified. Right, literally crucified on 00:00:12.300 --> 00:00:16.239 the job site. Not fired, not demoted. You're 00:00:16.239 --> 00:00:18.839 a criminal. Crucified. It's intense. Yeah, welcome 00:00:18.839 --> 00:00:21.480 to today's Deep Dive. We are traveling back to 00:00:21.480 --> 00:00:25.859 the Islamic golden age in ninth century Baghdad. 00:00:25.980 --> 00:00:27.760 Right. And we're going to explore the brilliant 00:00:27.760 --> 00:00:30.960 minds, the unprecedented inventions and the truly 00:00:30.960 --> 00:00:33.899 perilous workplace environment of the Bonamusa 00:00:33.899 --> 00:00:37.119 Brothers. It is a story that, honestly, it forces 00:00:37.119 --> 00:00:40.000 us to completely rethink how scientific progress 00:00:40.000 --> 00:00:41.939 actually happens. Absolutely. Because we tend 00:00:41.939 --> 00:00:44.420 to picture the history of science as this, like, 00:00:44.539 --> 00:00:47.380 orderly, civilized march forward in pristine 00:00:47.380 --> 00:00:49.659 laboratories, you know? But the reality here 00:00:49.659 --> 00:00:51.920 is scorching deserts, cutthroat palace intrigue, 00:00:52.060 --> 00:00:54.579 and literal highway robbery. OK, let's unpack 00:00:54.579 --> 00:00:57.020 this. Today we are pulling from a comprehensive 00:00:57.020 --> 00:00:59.359 Wikipedia article detailing the biographical 00:00:59.359 --> 00:01:02.280 timeline of these three brothers, Muammar, Ahmad, 00:01:02.490 --> 00:01:05.629 And also on the bun. Exactly. We're going to 00:01:05.629 --> 00:01:08.689 look at their surviving texts and how they managed 00:01:08.689 --> 00:01:12.230 to bridge ancient Greek theoretical math with 00:01:12.230 --> 00:01:15.209 like hand on physical engineering. They essentially 00:01:15.209 --> 00:01:18.430 built what might be the world's first programmable 00:01:18.430 --> 00:01:20.670 machine, which is just mind blowing for the ninth 00:01:20.670 --> 00:01:23.590 century. Right. But to understand how they achieved 00:01:23.590 --> 00:01:25.329 any of this, you really have to look at their 00:01:25.329 --> 00:01:29.099 origin story because their father. Musa ibn Shaqir 00:01:29.099 --> 00:01:33.040 was a bandit. He started his career as a highwayman 00:01:33.040 --> 00:01:35.799 in Khorasan, just robbing travelers. Which is 00:01:35.799 --> 00:01:38.159 an incredibly rare starting point for a family 00:01:38.159 --> 00:01:40.980 of legendary polymaths. I mean, yeah. We don't 00:01:40.980 --> 00:01:43.260 have the exact historical record of how he managed 00:01:43.260 --> 00:01:46.799 this pivot, but somehow this highway robber puts 00:01:46.799 --> 00:01:49.420 down his sword, studies the stars, and becomes 00:01:49.420 --> 00:01:51.920 a recognized astronomer. That's wild. And more 00:01:51.920 --> 00:01:54.519 importantly, he manages to befriend a man who 00:01:54.519 --> 00:01:57.790 would eventually become the Abbasid caliph And 00:01:57.790 --> 00:02:00.629 that friendship is the catalyst for everything. 00:02:01.230 --> 00:02:03.909 Because when the father dies, his three sons 00:02:03.909 --> 00:02:07.010 are left orphaned. But the caliph remembers his 00:02:07.010 --> 00:02:10.310 friend. He steps in, takes these three boys under 00:02:10.310 --> 00:02:13.169 his wing, assigns a senior Baghdad official as 00:02:13.169 --> 00:02:15.710 their guardian, and enrolls them in the House 00:02:15.710 --> 00:02:17.650 of Wisdom. The intellectual center of the world 00:02:17.650 --> 00:02:19.710 at that time. Yeah. I'm trying to think of a 00:02:19.710 --> 00:02:21.430 modern equivalent for you listening. And the 00:02:21.430 --> 00:02:25.849 closest thing would be if a superpower government 00:02:25.849 --> 00:02:29.960 scooped up three orphan kids and just drop them 00:02:29.960 --> 00:02:33.139 into a top -secret elite tech incubator with 00:02:33.139 --> 00:02:35.020 an unlimited black budget. That's a great way 00:02:35.020 --> 00:02:38.379 to put it. Right. They were handed every conceivable 00:02:38.379 --> 00:02:41.360 resource and trained by senior court astrologers 00:02:41.360 --> 00:02:44.340 in geometry, mechanics, music, and mathematics. 00:02:44.639 --> 00:02:46.280 Well, if we connect this to the bigger picture, 00:02:46.419 --> 00:02:48.080 you have to understand the environment they were 00:02:48.080 --> 00:02:50.419 dropped into. The Abbasid Caliphate at this time 00:02:50.419 --> 00:02:53.439 was completely obsessed with acquiring knowledge. 00:02:53.580 --> 00:02:55.620 Right. The translation movement. Exactly. This 00:02:55.620 --> 00:02:58.039 was the peak of the Great Translation Movement. 00:02:58.479 --> 00:03:00.860 The state's primary goal was to gather ancient 00:03:00.860 --> 00:03:03.780 Greek texts from Byzantium, you know, works of 00:03:03.780 --> 00:03:06.599 philosophy, mathematics, engineering, and translate 00:03:06.599 --> 00:03:08.719 them into Arabic. And the Bani Musa brothers 00:03:08.719 --> 00:03:10.659 didn't just sit in a classroom reading these 00:03:10.659 --> 00:03:13.240 texts. As they grew older and acquired immense 00:03:13.240 --> 00:03:16.340 state -sponsored wealth, they became major power 00:03:16.340 --> 00:03:19.060 players in this movement. Yeah. The sources say 00:03:19.060 --> 00:03:22.259 they were personally paying translators 500 dinars 00:03:22.259 --> 00:03:24.719 a month. Which is a staggering fortune. To put 00:03:24.719 --> 00:03:26.800 that in perspective, yeah, it was massive. They 00:03:26.800 --> 00:03:28.879 were funding these massive expeditions just to 00:03:28.879 --> 00:03:31.259 hunt down ancient manuscripts. Oh, totally. They 00:03:31.259 --> 00:03:33.280 even traveled to Byzantium themselves to find 00:03:33.280 --> 00:03:37.219 these books. what stands out to me is their eye 00:03:37.219 --> 00:03:41.180 for raw, unconventional talent. Yes, the Thabit 00:03:41.180 --> 00:03:43.860 Dibbinkora story. Exactly, there's this one specific 00:03:43.860 --> 00:03:47.280 story where the eldest brother, Muthamad, is 00:03:47.280 --> 00:03:49.639 traveling back to Baghdad, and he happens to 00:03:49.639 --> 00:03:52.419 stop at a currency exchange stall in Haran. He 00:03:52.419 --> 00:03:54.819 starts talking to the money changer, a man named 00:03:54.819 --> 00:03:57.620 Thabit Dibbinkora. And a money changer is someone 00:03:57.620 --> 00:04:01.219 dealing constantly in fractions, conversion rates, 00:04:01.840 --> 00:04:04.780 rapid mental arithmetic. Right, exactly. So Momod 00:04:04.780 --> 00:04:07.180 recognized that the man wasn't just doing basic 00:04:07.180 --> 00:04:10.060 commerce, you know. He had a profound intuitive 00:04:10.060 --> 00:04:13.340 grasp of complex mathematics. So Momod just recruits 00:04:13.340 --> 00:04:15.539 him on the spot. Literally just takes him. Yeah, 00:04:15.659 --> 00:04:17.339 he pulls him out of the market and brings him 00:04:17.339 --> 00:04:19.970 into their inner circle. and that money changer 00:04:19.970 --> 00:04:23.110 goes on to make massive historical discoveries 00:04:23.110 --> 00:04:25.910 in algebra and geometry. It's incredible. It 00:04:25.910 --> 00:04:28.970 really proves that genius isn't confined to academic 00:04:28.970 --> 00:04:32.350 institutions. If you have the vision and, well, 00:04:32.509 --> 00:04:34.990 the funding to look for it, you can find brilliant 00:04:34.990 --> 00:04:38.509 minds working at a currency exchange stall. Absolutely. 00:04:38.750 --> 00:04:41.370 And that wealth gave them the freedom to not 00:04:41.370 --> 00:04:44.970 just archive knowledge, but to aggressively test 00:04:44.970 --> 00:04:47.149 it in the real world. Right. They were working 00:04:47.149 --> 00:04:50.029 alongside titans of the era, like Al -Khorizmi 00:04:50.029 --> 00:04:53.350 and Al -Kindi, but the brothers were unique because 00:04:53.350 --> 00:04:55.970 they weren't satisfied with merely translating 00:04:55.970 --> 00:04:57.949 what the ancient Greeks thought about the universe. 00:04:57.970 --> 00:05:00.050 They wanted to prove it. Exactly. They demanded 00:05:00.050 --> 00:05:02.189 empirical proof. Which brings us to a project 00:05:02.189 --> 00:05:04.389 that sounds like an absolute logistical nightmare. 00:05:04.680 --> 00:05:07.199 So the ancient Greeks had theorized that the 00:05:07.199 --> 00:05:09.600 circumference of the earth was roughly 25 ,000 00:05:09.600 --> 00:05:12.920 miles. Right. Eratosthenes. Yeah. And the Caliph 00:05:12.920 --> 00:05:15.339 Alma Moon basically issues a challenge. He's 00:05:15.339 --> 00:05:19.000 like, go verify that. Now, imagine you are tasked 00:05:19.000 --> 00:05:21.800 with measuring the entire planet, but you are 00:05:21.800 --> 00:05:24.199 living in the ninth century. Good luck. Right. 00:05:24.420 --> 00:05:26.459 You don't have satellites. You don't have lasers. 00:05:26.800 --> 00:05:29.680 The brothers' solution was to travel out to the 00:05:29.680 --> 00:05:33.379 desert near Sanjar in northern Mesopotamia, equipped 00:05:33.379 --> 00:05:36.579 with essentially nothing but wooden pegs, long 00:05:36.579 --> 00:05:39.399 ropes, and the night sky. Their methodology was 00:05:39.399 --> 00:05:41.579 brilliantly elegant, though. Walk us through 00:05:41.579 --> 00:05:44.699 it. So they waited until nightfall and measured 00:05:44.699 --> 00:05:47.500 the exact altitude of the pole star in the sky. 00:05:47.839 --> 00:05:50.779 Then they started walking due north. Okay. As 00:05:50.779 --> 00:05:53.680 they walked, they drove wooden pegs into the 00:05:53.680 --> 00:05:56.240 hard desert ground and stretched a rope tightly 00:05:56.240 --> 00:05:58.240 between them to ensure they were walking in a 00:05:58.240 --> 00:06:00.560 perfectly straight line, measuring the exact 00:06:00.560 --> 00:06:02.899 distance they covered. Right. They kept walking 00:06:02.899 --> 00:06:05.199 north until the altitude of the pole star changed 00:06:05.199 --> 00:06:08.120 by exactly one degree. Then they returned to 00:06:08.120 --> 00:06:10.079 their starting point and did the exact same thing, 00:06:10.319 --> 00:06:12.360 walking due south. See, I'm trying to picture 00:06:12.360 --> 00:06:14.579 the sheer physical toll of this. You're in the 00:06:14.579 --> 00:06:16.319 Mesopotamian desert. Whoa, it would have been 00:06:16.319 --> 00:06:19.930 grueling. But beyond that... I just have to challenge 00:06:19.930 --> 00:06:22.290 the accuracy here. You're telling me they used 00:06:22.290 --> 00:06:25.129 a giant protractor and a long piece of string 00:06:25.129 --> 00:06:28.089 to measure a planet? Essentially, yes. Wait, 00:06:28.329 --> 00:06:30.370 how do you account for a rope stretching in the 00:06:30.370 --> 00:06:32.569 midday heat or just the fact that humans naturally 00:06:32.569 --> 00:06:34.889 drift and don't walk in perfectly straight lines, 00:06:35.209 --> 00:06:37.269 especially over dunes and uneven terrain? Well, 00:06:37.449 --> 00:06:39.790 those are the exact variables that ruin scientific 00:06:39.790 --> 00:06:41.569 experiments, right? Yeah. And the brothers knew 00:06:41.569 --> 00:06:44.329 it. That is why they didn't just do it once. 00:06:44.910 --> 00:06:47.329 The brilliance of their work lies in the rigorous 00:06:47.329 --> 00:06:50.310 repetition. By walking both north and south, 00:06:50.569 --> 00:06:53.470 they averaged out local topographical errors, 00:06:53.970 --> 00:06:56.759 but they went further. They packed up the entire 00:06:56.759 --> 00:06:59.120 expedition, traveled to a completely different 00:06:59.120 --> 00:07:01.800 geographical location, Al -Kufa, and repeated 00:07:01.800 --> 00:07:05.399 the entire grueling process all over again. Wow. 00:07:05.620 --> 00:07:07.199 Okay, so they were verifying their own data. 00:07:07.519 --> 00:07:10.060 Exactly. They were actively trying to control 00:07:10.060 --> 00:07:12.860 four environmental variables. By measuring the 00:07:12.860 --> 00:07:14.939 physical distance on the ground that corresponded 00:07:14.939 --> 00:07:17.180 to a one -degree change in the star's altitude, 00:07:17.459 --> 00:07:21.279 they knew they had measured exactly one 360th 00:07:21.279 --> 00:07:24.000 of the Earth's circumference. Multiply that distance 00:07:24.000 --> 00:07:27.990 by 360. and they arrived at their answer, 24 00:07:27.990 --> 00:07:31.810 ,000 miles. Which is astonishingly close to the 00:07:31.810 --> 00:07:35.569 actual figure of about 24 ,900 miles. It's incredible. 00:07:35.769 --> 00:07:38.569 They achieve that precision using sticks, string, 00:07:38.850 --> 00:07:40.490 and exhaustion. Pretty much. And you can see 00:07:40.490 --> 00:07:43.490 that transition from theoretical to hyper practical 00:07:43.490 --> 00:07:45.970 in their mathematical text too. Specifically, 00:07:46.560 --> 00:07:48.500 Their treat is called the book on the measurement 00:07:48.500 --> 00:07:51.399 of plane and spherical figures. Oh, that specific 00:07:51.399 --> 00:07:54.360 book was foundational. Medieval mathematicians 00:07:54.360 --> 00:07:57.100 like Fibonacci used it centuries later. Wow, 00:07:57.279 --> 00:07:59.819 really? Yeah. The reason it was so revolutionary 00:07:59.819 --> 00:08:01.860 is that it fundamentally broke away from the 00:08:01.860 --> 00:08:04.980 Greek tradition of geometry. Think about Euclid 00:08:04.980 --> 00:08:07.600 or Archimedes. When the Greeks did geometry, 00:08:07.920 --> 00:08:10.139 they thought in terms of abstract ratios. OK, 00:08:10.199 --> 00:08:12.560 like how? They would say that the area of a circle 00:08:12.560 --> 00:08:15.339 relates to its radius in a specific proportional 00:08:15.339 --> 00:08:17.980 relationship. It was a philosophical way of looking 00:08:17.980 --> 00:08:20.860 at shapes. But the Banu and Musa brothers needed 00:08:20.860 --> 00:08:23.560 something more concrete. They shifted that paradigm 00:08:23.560 --> 00:08:27.639 by expressing area and circumference as actual 00:08:27.639 --> 00:08:31.560 hard numerical values. It is the difference between 00:08:31.560 --> 00:08:34.460 reading a recipe that says use twice as much 00:08:34.460 --> 00:08:37.700 flour as sugar versus a recipe that says pour 00:08:37.700 --> 00:08:41.000 in exactly 500 grams of flour. That's a perfect 00:08:41.000 --> 00:08:43.679 analogy. One is relational concept. The other 00:08:43.679 --> 00:08:46.320 is an actionable blueprint. And that shift is 00:08:46.320 --> 00:08:48.620 the critical leap between a philosopher and an 00:08:48.620 --> 00:08:50.700 engineer. If you want to actually build a physical 00:08:50.700 --> 00:08:53.419 machine, ratios aren't enough. You need exact 00:08:53.419 --> 00:08:55.740 numbers. You need exact numbers to know how much 00:08:55.740 --> 00:08:58.519 brass to cut or exactly how much water a cylinder 00:08:58.519 --> 00:09:00.960 can hold. Because they had finally nailed down 00:09:00.960 --> 00:09:03.759 how to use exact, concrete numbers, they could 00:09:03.759 --> 00:09:06.419 start building physical working mechanisms. Which 00:09:06.419 --> 00:09:08.879 perfectly explains the middle brother, A -mad. 00:09:09.120 --> 00:09:11.620 He is the author of the book of Ingenious Devices, 00:09:12.059 --> 00:09:14.559 a manuscript detailing a hundred different physical 00:09:14.559 --> 00:09:16.600 inventions. Yes. And looking at the breakdown 00:09:16.600 --> 00:09:18.740 of this book is hilarious because it highlights 00:09:18.740 --> 00:09:21.320 the dual nature of engineering. Out of the hundred 00:09:21.320 --> 00:09:24.379 inventions, about 25 are highly practical, life 00:09:24.379 --> 00:09:27.179 -saving tools. We are talking about genuine industrial 00:09:27.179 --> 00:09:30.279 innovation here. They designed a gas mask for 00:09:30.279 --> 00:09:32.539 workers exploring polluted underground wells. 00:09:33.039 --> 00:09:35.519 They built a hurricane lamp designed to withstand 00:09:35.519 --> 00:09:38.480 high winds without blowing out. They even engineered 00:09:38.480 --> 00:09:40.899 a mechanical grabbing tool for recovering heavy 00:09:40.899 --> 00:09:43.639 objects underwater. Right. The clamshell design. 00:09:43.779 --> 00:09:46.279 Yeah. The source material notes that it was constructed 00:09:46.279 --> 00:09:49.600 using two hinged toothed buckets that snapped 00:09:49.600 --> 00:09:52.340 together under rope tension, which is the exact 00:09:52.340 --> 00:09:55.039 same mechanical principle as the clamshell grabber 00:09:55.039 --> 00:09:57.639 you see on a modern construction excavator. It's 00:09:57.639 --> 00:10:00.340 identical. But that leaves 75 other inventions 00:10:00.340 --> 00:10:03.419 in the book. The vast majority of A -Man's work 00:10:03.419 --> 00:10:06.419 was dedicated to trick -pouring vessels. Party 00:10:06.419 --> 00:10:08.840 tricks. Pictures designed for fancy banquets 00:10:08.840 --> 00:10:11.460 that would pour wine, then pour water, and then 00:10:11.460 --> 00:10:14.360 pour a mixture of both, seemingly by magic. They 00:10:14.360 --> 00:10:16.500 were essentially ninth -century parlor tricks 00:10:16.500 --> 00:10:20.299 designed to confuse rich guests. It is easy to 00:10:20.299 --> 00:10:22.899 dismiss those pictures as frivolous toys. But 00:10:22.899 --> 00:10:25.320 what's fascinating here is that the significance 00:10:25.320 --> 00:10:27.940 for the history of engineering isn't what the 00:10:27.940 --> 00:10:30.659 pitchers did, it is how they functioned. Okay, 00:10:30.779 --> 00:10:32.919 explain that. The trick pitcher was merely a 00:10:32.919 --> 00:10:35.639 physical shell hiding a labyrinth of fluid dynamics. 00:10:36.259 --> 00:10:38.159 To make a pitcher pour two different liquids 00:10:38.159 --> 00:10:40.419 automatically without the user doing anything, 00:10:40.960 --> 00:10:43.080 Ahmad had to invent automatic one -way and two 00:10:43.080 --> 00:10:45.899 -way valves. He built concentric siphons. Wait, 00:10:45.960 --> 00:10:48.460 break that down for me. How do you build a mechanical 00:10:48.460 --> 00:10:52.220 delay? out of just water and gravity. Okay, imagine 00:10:52.220 --> 00:10:55.720 a hidden secondary tank inside the pitcher. As 00:10:55.720 --> 00:10:58.940 you pour the first liquid, water is also slowly 00:10:58.940 --> 00:11:01.879 bleeding into this hidden chamber. Inside that 00:11:01.879 --> 00:11:05.200 chamber is a piece of cork, a float valve, very 00:11:05.200 --> 00:11:07.220 similar to the ball floating in the back of your 00:11:07.220 --> 00:11:09.379 modern toilet tank. Oh, I see where this is going. 00:11:09.480 --> 00:11:11.840 Right. As the hidden chamber fills, the cork 00:11:11.840 --> 00:11:14.879 rises. Once the water reaches a specific height, 00:11:15.120 --> 00:11:17.720 the rising cork trips a hidden lever, which snaps 00:11:17.720 --> 00:11:20.200 a valve shut and opens a new one, changing the 00:11:20.200 --> 00:11:22.720 liquid being poured. That is so clever. The time 00:11:22.720 --> 00:11:25.120 it takes for that hidden tank to fill up creates 00:11:25.120 --> 00:11:27.779 a physical delay. It is a timer made entirely 00:11:27.779 --> 00:11:30.360 out of fluid pressure and gravity. They were 00:11:30.360 --> 00:11:32.820 creating even statements using water. Here's 00:11:32.820 --> 00:11:35.519 where it gets really interesting. Because they 00:11:35.519 --> 00:11:38.559 took those if in statements, those control valves, 00:11:39.059 --> 00:11:40.679 and they applied them to a completely different 00:11:40.679 --> 00:11:43.360 medium. Yes, they did. It's detailed in a separate 00:11:43.360 --> 00:11:45.980 manuscript called The Book on the Description 00:11:45.980 --> 00:11:49.580 of the Instrument, which sounds by itself. This 00:11:49.580 --> 00:11:52.679 wasn't a water pitcher. It was a massive automatic 00:11:52.679 --> 00:11:55.620 flute player. The conceptual leap here is just, 00:11:55.620 --> 00:11:58.019 it's astonishing. They took the principles of 00:11:58.019 --> 00:12:00.539 fluid control and used them to sequence information. 00:12:00.720 --> 00:12:03.419 The mechanism is brilliant. Think of a child's 00:12:03.419 --> 00:12:05.960 wind up music box. The kind of with a rotating 00:12:05.960 --> 00:12:08.139 metal cylinder covered in little raised bumps 00:12:08.139 --> 00:12:10.399 that pluck metal teeth to make a song. Right. 00:12:10.600 --> 00:12:13.120 Everyone knows those. Now, scale that up and 00:12:13.120 --> 00:12:16.080 power it with a steam engine concept. The brothers 00:12:16.080 --> 00:12:18.860 used continuous water pressure to slowly rotate 00:12:18.860 --> 00:12:21.779 a large cylinder covered in strategically placed 00:12:21.779 --> 00:12:24.940 pins. As the cylinder turned, those pins pushed 00:12:24.940 --> 00:12:27.720 against levers. The levers acted like human fingers, 00:12:27.919 --> 00:12:29.879 dropping down to open and close the holes on 00:12:29.879 --> 00:12:32.779 a flute, while steam or steady air pressure was 00:12:32.779 --> 00:12:35.669 forced through the mouthpiece. and the most revolutionary 00:12:35.669 --> 00:12:39.070 part. You could pull that pin cylinder out and 00:12:39.070 --> 00:12:41.830 swap it for a different cylinder with a different 00:12:41.830 --> 00:12:43.730 pattern of pins. And it would play a new song. 00:12:44.009 --> 00:12:45.889 Exactly. The machine would play a completely 00:12:45.889 --> 00:12:48.889 different song. That is physical coding. Yeah. 00:12:49.350 --> 00:12:52.350 They separated the hardware, the air pressure, 00:12:52.429 --> 00:12:56.100 and the levers from the software. The pin cylinder. 00:12:56.299 --> 00:12:58.740 Yes. They essentially invented a programmable 00:12:58.740 --> 00:13:02.179 machine, an early music sequencer, hundreds of 00:13:02.179 --> 00:13:04.639 years before the Industrial Revolution. It really 00:13:04.639 --> 00:13:07.200 is an early computer. Now you would assume that 00:13:07.200 --> 00:13:10.120 inventing gas masks, measuring the globe, and 00:13:10.120 --> 00:13:12.639 building the first programmable robots would 00:13:12.639 --> 00:13:14.779 make the brothers universally beloved. You would 00:13:14.779 --> 00:13:18.100 think so. But extreme brilliance combined with 00:13:18.100 --> 00:13:20.779 limitless state funding often breeds extreme 00:13:20.779 --> 00:13:23.320 arrogance. And they were incredibly arrogant. 00:13:23.419 --> 00:13:26.179 As they accumulated wealth under successive caliphs, 00:13:26.299 --> 00:13:29.000 they became deeply entrenched in court politics. 00:13:29.039 --> 00:13:31.259 Very deeply. They were basically the real housewives 00:13:31.259 --> 00:13:34.059 of 9th century Baghdad. They used their proximity 00:13:34.059 --> 00:13:36.679 to power to ruthlessly crush anyone they viewed 00:13:36.679 --> 00:13:39.220 as a rival. And the most glaring example of this 00:13:39.220 --> 00:13:41.759 is their treatment of al -Kindi, who was himself 00:13:41.759 --> 00:13:44.860 a legendary philosopher and mathematician. Yeah, 00:13:44.980 --> 00:13:47.639 the brothers viewed him as a threat to their 00:13:47.639 --> 00:13:50.700 monopoly on the caliph's favor. So they started 00:13:50.700 --> 00:13:53.919 by academically bullying him. harshly mocking 00:13:53.919 --> 00:13:57.120 his writings on the astrolabe. Just petty academic 00:13:57.120 --> 00:13:59.779 stuff at first. Right. But academic debate wasn't 00:13:59.779 --> 00:14:02.269 enough. They leveraged their political influence 00:14:02.269 --> 00:14:05.389 to have al -Kindi physically beaten. Which is 00:14:05.389 --> 00:14:07.309 just awful. They have banished from the court 00:14:07.309 --> 00:14:10.049 and then they confiscated his entire personal 00:14:10.049 --> 00:14:13.210 library. It's his workplace toxicity on a staggering 00:14:13.210 --> 00:14:15.629 scale. But when your entire career depends on 00:14:15.629 --> 00:14:18.850 the favor of an absolute monarch, playing political 00:14:18.850 --> 00:14:21.850 games is an existential risk. If you make enemies, 00:14:21.970 --> 00:14:24.190 you better not make any mistakes. Which brings 00:14:24.190 --> 00:14:27.070 us to the Jafferet Canal disaster. Oh boy. The 00:14:27.070 --> 00:14:29.750 Caliph al -Mutawakil decides to build a massive 00:14:29.750 --> 00:14:33.149 new city, and he demands the Banu Musa oversee 00:14:33.149 --> 00:14:35.690 the construction of a vital canal to supply it 00:14:35.690 --> 00:14:38.230 with water. The brothers, perhaps feeling that 00:14:38.230 --> 00:14:40.750 digging ditches was beneath their immense intellect, 00:14:41.409 --> 00:14:43.889 delegate the actual engineering and surveying 00:14:43.889 --> 00:14:46.909 work to a man named Al Fargani. And Al Fargani 00:14:46.909 --> 00:14:49.509 makes a catastrophic error in fluid dynamics. 00:14:50.210 --> 00:14:52.490 He digs the origin of the canal deeper than the 00:14:52.490 --> 00:14:55.100 destination. Water does not flow uphill. No, 00:14:55.159 --> 00:14:57.220 it does not. Once the canal is completed and 00:14:57.220 --> 00:14:58.840 the water is let in, it isn't going to flow into 00:14:58.840 --> 00:15:01.320 the new city. It is going to drain away completely 00:15:01.320 --> 00:15:04.019 into the desert. Exactly. The ultimate masters 00:15:04.019 --> 00:15:07.360 of fluid pressure somehow oversaw a project that 00:15:07.360 --> 00:15:10.360 fundamentally failed at moving water. And the 00:15:10.360 --> 00:15:12.600 caliph finds out. And the caliph's response is 00:15:12.600 --> 00:15:15.059 swift and brutal. He decrees that on the day 00:15:15.059 --> 00:15:17.580 the canal is opened, if the water fails to reach 00:15:17.580 --> 00:15:20.590 the city. the Banu Musta brothers will be crucified 00:15:20.590 --> 00:15:23.330 on crosses erected right beside the dry riverbed. 00:15:23.830 --> 00:15:27.070 I just marvel at the absolute terror of that 00:15:27.070 --> 00:15:29.370 four -month waiting period. Imagine standing 00:15:29.370 --> 00:15:31.730 on a construction site, looking at a dry ditch, 00:15:32.309 --> 00:15:34.210 knowing a mathematical error is going to end 00:15:34.210 --> 00:15:36.490 with you nailed to a piece of wood. They needed 00:15:36.490 --> 00:15:38.889 a miracle, or they needed someone willing to 00:15:38.889 --> 00:15:41.590 risk their own life to cover for them. And the 00:15:41.590 --> 00:15:44.289 person who steps in to save them is a consultant 00:15:44.289 --> 00:15:48.049 engineer named Sanad Binah. But here is the massive 00:15:48.049 --> 00:15:51.110 twist. Sanad Binah was close friends with Al 00:15:51.110 --> 00:15:53.490 -Kindi. The same scholar the brothers had beaten 00:15:53.490 --> 00:15:56.309 and robbed. The irony is thick. The brothers' 00:15:56.370 --> 00:15:58.669 lives are entirely in the hands of a man whose 00:15:58.669 --> 00:16:00.730 best friend they destroyed. It's like something 00:16:00.730 --> 00:16:03.269 out of a movie. Right. Sanad Binah approaches 00:16:03.269 --> 00:16:05.889 the terrified brothers and offers a deal. He 00:16:05.889 --> 00:16:08.529 says, I will save your lives, but my condition 00:16:08.529 --> 00:16:10.950 is that you immediately return Al -Kindi's library. 00:16:11.519 --> 00:16:13.620 And they agree instantly. Oh, of course they 00:16:13.620 --> 00:16:16.220 do. So Sanad goes to the Caliph. Now, Sanad knows 00:16:16.220 --> 00:16:18.740 the canal is a total failure, but he also knows 00:16:18.740 --> 00:16:21.700 a piece of court gossip. Ah, the astrologers. 00:16:21.799 --> 00:16:24.360 Yes. The royal astrologers have recently predicted 00:16:24.360 --> 00:16:26.799 that the Caliph only has a few months left to 00:16:26.799 --> 00:16:29.340 live. He decides to gamble his own life on a 00:16:29.340 --> 00:16:31.840 horoscope. He lies directly to the Caliph's face. 00:16:32.740 --> 00:16:35.139 He proclaims that the canal is perfectly engineered. 00:16:35.600 --> 00:16:38.860 buying the brothers time. Wow. For months, Sanad 00:16:38.860 --> 00:16:41.360 and the brothers sweated out, waiting to see 00:16:41.360 --> 00:16:43.460 if the water will drop before the caliph drops. 00:16:43.580 --> 00:16:46.399 Talk about high stakes. Right. And incredibly, 00:16:46.539 --> 00:16:50.159 the gamble pays off. Just months before the canal's 00:16:50.159 --> 00:16:52.899 failure would become undeniable, the Caliph al 00:16:52.899 --> 00:16:55.860 -Nutawakil is assassinated. This raises an important 00:16:55.860 --> 00:16:58.480 question about the reality of state -sponsored 00:16:58.480 --> 00:17:00.639 science in the ancient world. What do you mean? 00:17:01.080 --> 00:17:03.480 Well, we love to romanticize the house of wisdom 00:17:03.480 --> 00:17:05.740 and the endless flow of gold for translation 00:17:05.740 --> 00:17:09.839 and research, but the sword cuts both ways. The 00:17:09.839 --> 00:17:12.160 Banu Musa brothers had limitless funding, but 00:17:12.160 --> 00:17:14.779 their genius, their research, and their literal 00:17:14.779 --> 00:17:18.099 survival were entirely subject to the unpredictable 00:17:18.099 --> 00:17:21.359 moods, the whims, and the lifespans of absolute 00:17:21.359 --> 00:17:23.440 rulers. Yeah, it was a perilous way to innovate. 00:17:23.680 --> 00:17:25.680 But innovate they did. They escaped execution, 00:17:25.819 --> 00:17:27.599 the library was returned, and they went right 00:17:27.599 --> 00:17:31.329 back to their work. The eldest, Muthamad, even 00:17:31.329 --> 00:17:33.509 ended up negotiating military sieges later in 00:17:33.509 --> 00:17:36.250 his life, just continuing this relentlessly chaotic 00:17:36.250 --> 00:17:39.569 existence until his death in January 873. They 00:17:39.569 --> 00:17:41.990 lived large. But when you strip away the political 00:17:41.990 --> 00:17:44.869 madness, their legacy is undeniably monumental. 00:17:45.190 --> 00:17:47.589 They took abstract Greek theory, forced it into 00:17:47.589 --> 00:17:50.190 concrete numerical values, and used those numbers 00:17:50.190 --> 00:17:52.509 to manipulate the physical world in ways no one 00:17:52.509 --> 00:17:56.049 had ever seen. They are the vital bridge. They 00:17:56.049 --> 00:17:58.730 pushed humanity past philosophical observation 00:17:58.730 --> 00:18:01.890 and into the realm of automated control. So what 00:18:01.890 --> 00:18:04.329 does this all mean? Why should you care about 00:18:04.329 --> 00:18:07.049 three chaotic brothers from 9th century Baghdad? 00:18:07.109 --> 00:18:09.490 Oh, right. Because the next time you set up a 00:18:09.490 --> 00:18:11.630 smart home routine on your phone to turn on your 00:18:11.630 --> 00:18:14.369 lights at sunset, or you watch an automated sprinkler 00:18:14.369 --> 00:18:17.009 system adjust its own water pressure, or even 00:18:17.009 --> 00:18:19.269 if you just drop a coin into a claw machine at 00:18:19.269 --> 00:18:22.150 a local arcade to grab a stuffed animal, you 00:18:22.150 --> 00:18:24.529 are experiencing the distant echoes of their 00:18:24.529 --> 00:18:26.750 work. You really are. You are interacting with 00:18:26.750 --> 00:18:29.450 the legacy of three orphan boys who use ropes 00:18:29.450 --> 00:18:31.950 and pegs to measure the planet, and who forced 00:18:31.950 --> 00:18:34.579 water to become the world's first computer. And 00:18:34.579 --> 00:18:37.819 it leaves us with one final, profound thought 00:18:37.819 --> 00:18:40.400 to consider. What's that? When we look back at 00:18:40.400 --> 00:18:42.599 the book of ingenious devices, the vast majority 00:18:42.599 --> 00:18:45.299 of those incredible mechanical leaps, the automated 00:18:45.299 --> 00:18:48.559 valves, the mechanical delays, the feedback loops, 00:18:48.579 --> 00:18:50.400 they weren't built for industry. Right, they 00:18:50.400 --> 00:18:52.700 were for the parties. They were originally designed 00:18:52.700 --> 00:18:56.019 simply to entertain party guests. They were frivolous 00:18:56.019 --> 00:18:59.480 toys. It makes you wonder... What obscure video 00:18:59.480 --> 00:19:01.559 game mechanics or seemingly pointless digital 00:19:01.559 --> 00:19:03.799 toys being developed right now just for entertainment 00:19:03.799 --> 00:19:06.460 are secretly laying the invisible functional 00:19:06.460 --> 00:19:09.400 foundations for our most critical future technology. 00:19:09.839 --> 00:19:11.940 From a magic trick at a party to the future of 00:19:11.940 --> 00:19:14.099 engineering. Thanks for joining us on this deep 00:19:14.099 --> 00:19:14.339 dive.