WEBVTT 00:00:00.000 --> 00:00:02.480 Welcome back to the Deep Dive. Our mission here 00:00:02.480 --> 00:00:05.200 is simple. We tear through a stack of sources, 00:00:05.559 --> 00:00:07.960 extract the vital knowledge, and deliver it to 00:00:07.960 --> 00:00:10.779 you as a high -octane intellectual shortcut. 00:00:11.019 --> 00:00:13.779 And today, we're taking on, well, maybe the most 00:00:13.779 --> 00:00:16.519 colossal mind in Western history. It feels that 00:00:16.519 --> 00:00:20.359 way. We are synthesizing the life, the art, and 00:00:20.359 --> 00:00:23.579 the frankly unbelievable scientific genius of 00:00:23.579 --> 00:00:26.160 the high renaissance's quintessential polymath. 00:00:26.539 --> 00:00:28.480 Leonardo da Vinci. It's not just a challenge 00:00:28.480 --> 00:00:30.579 it's an absolute rabbit hole. I mean we're dealing 00:00:30.579 --> 00:00:34.619 with a human being who truly defied categorization. 00:00:34.719 --> 00:00:37.280 He really did. A painter, a draftsman, engineer, 00:00:37.659 --> 00:00:40.479 a military architect, scientist, anatomist, a 00:00:40.479 --> 00:00:43.460 theorist. The sources consistently describe him 00:00:43.460 --> 00:00:46.119 as possessing an unquenchable curiosity. And 00:00:46.119 --> 00:00:48.719 that phrase I love, a feverishly inventive imagination. 00:00:49.200 --> 00:00:51.320 Yes, he was the very embodiment of the Renaissance 00:00:51.320 --> 00:00:54.340 humanist ideal. That phrase, feverishly inventive 00:00:54.340 --> 00:00:56.399 imagination, I think that has to be our anchor 00:00:56.399 --> 00:00:58.719 because our goal today is to move beyond the 00:00:58.719 --> 00:01:01.060 famous, you know, the familiar portrait. Beyond 00:01:01.060 --> 00:01:04.890 the smile. Exactly. Beyond the smile to understand 00:01:04.890 --> 00:01:08.370 the full revolutionary scope of his genius. We 00:01:08.370 --> 00:01:10.689 need to uncover his groundbreaking and often 00:01:10.689 --> 00:01:13.530 unpublished work in anatomy, in engineering. 00:01:13.870 --> 00:01:17.010 Tribology, even. Tribology, right. And most importantly, 00:01:17.129 --> 00:01:20.409 we need to address that central paradox. Why 00:01:20.409 --> 00:01:22.969 did this towering intellect, whose notes contain 00:01:22.969 --> 00:01:25.609 epoch -making discoveries, have so little direct 00:01:25.609 --> 00:01:28.030 published influence during his lifetime? And 00:01:28.030 --> 00:01:29.950 to set the baseline before we even jump into 00:01:29.950 --> 00:01:32.469 all that science, we have to acknowledge his 00:01:32.469 --> 00:01:35.650 artistic legacy first. It's immense. Of course. 00:01:35.849 --> 00:01:37.890 Historians have noted that his collective works, 00:01:38.030 --> 00:01:40.250 I mean, they represent a contribution to the 00:01:40.250 --> 00:01:42.870 subsequent generations of European artists matched 00:01:42.870 --> 00:01:45.329 only by his younger contemporary, Michelangelo. 00:01:45.370 --> 00:01:48.290 His visual impact is just undeniable. Okay, so 00:01:48.290 --> 00:01:49.870 let's start at the beginning. Let's unpack his 00:01:49.870 --> 00:01:52.250 origin story. Before we get to the genius, who 00:01:52.250 --> 00:01:55.489 was he? Where did he come from? That name, Leonardo 00:01:55.489 --> 00:01:58.049 da Vinci, it's not really a family name, is it? 00:01:58.129 --> 00:02:00.250 No, not in the modern sense. It's more of a geographic 00:02:00.250 --> 00:02:02.870 marker. His full name was Leonardo di Serpiero 00:02:02.870 --> 00:02:04.870 da Vinci. Okay, break that down for us. It's 00:02:04.870 --> 00:02:08.310 simple, really. Leonardo, son of Serpiero, from 00:02:08.310 --> 00:02:11.229 the town of Vinci. So he was born in, or at least 00:02:11.229 --> 00:02:13.849 near, the Tuscan Hill town of Vinci, which is 00:02:13.849 --> 00:02:16.520 about 20 miles outside of Florence. April 15th, 00:02:16.520 --> 00:02:19.680 1452. So the da Vinci part is just from Vinci. 00:02:20.080 --> 00:02:23.419 Exactly. It's just a place name. And the circumstances 00:02:23.419 --> 00:02:26.080 of his birth are actually really revealing about 00:02:26.080 --> 00:02:28.919 his education and, well, his later trajectory. 00:02:29.120 --> 00:02:32.020 How so? He was born out of wedlock. His father 00:02:32.020 --> 00:02:34.759 was Sir Piero, a successful Florentine legal 00:02:34.759 --> 00:02:37.580 notary, a man of some standing. But his mother 00:02:37.580 --> 00:02:40.340 was a woman named Caterina di Meolipi, described 00:02:40.340 --> 00:02:44.689 in the sources as a lower class woman. They never 00:02:44.689 --> 00:02:46.629 married. No, they both married other people the 00:02:46.629 --> 00:02:49.090 year after Leonardo was born. And this social 00:02:49.090 --> 00:02:51.430 reality had profound implications for him. Right. 00:02:51.509 --> 00:02:53.909 Because in the Renaissance, that illegitimate 00:02:53.909 --> 00:02:55.990 status, it would have closed certain doors. It 00:02:55.990 --> 00:02:58.449 absolutely did. Because he was born outside those 00:02:58.449 --> 00:03:01.409 strict societal bounds. He only received a basic 00:03:01.409 --> 00:03:04.270 informal education. He learned to read. He learned 00:03:04.270 --> 00:03:06.150 vernacular writing, some rudimentary mathematics. 00:03:06.550 --> 00:03:09.099 So not the important stuff for a scholar. Critically, 00:03:09.159 --> 00:03:11.659 no. He did not receive the classical education 00:03:11.659 --> 00:03:15.939 in Latin that was mandatory for anyone aspiring 00:03:15.939 --> 00:03:18.539 to a university degree or scholarly pursuits, 00:03:18.580 --> 00:03:21.680 especially something like law or advanced medicine. 00:03:22.000 --> 00:03:24.000 And the theory is that his family just saw his 00:03:24.000 --> 00:03:26.500 artistic talent so early on. That's the common 00:03:26.500 --> 00:03:29.539 theory, yes. They recognized his prodigious artistic 00:03:29.539 --> 00:03:32.560 talent and decided to focus their resources there. 00:03:32.620 --> 00:03:34.639 It was a more practical path for him. And that 00:03:34.639 --> 00:03:37.159 lack of formal Latin, the language of European 00:03:37.159 --> 00:03:39.319 scholarship at the time, that's going to become 00:03:39.319 --> 00:03:41.479 the key intellectual roadblock for his scientific 00:03:41.479 --> 00:03:45.879 work centuries later. A catastrophic irony. It's 00:03:45.879 --> 00:03:47.539 unbelievable. The very tools of communication 00:03:47.539 --> 00:03:49.639 he lacked were the things that would have instantly 00:03:49.639 --> 00:03:52.280 validated his revolutionary findings in the eyes 00:03:52.280 --> 00:03:54.900 of his peers. So that background leads us straight 00:03:54.900 --> 00:03:57.120 into our first section, the artist's crucible. 00:03:57.199 --> 00:04:00.360 This is from his birth in 1452 to about 1500. 00:04:00.819 --> 00:04:03.180 In his real education, it wasn't a schoolhouse. 00:04:03.460 --> 00:04:05.780 No, it was a workshop. The real training began 00:04:05.780 --> 00:04:08.500 when he moved to Florence around age 14 and became 00:04:08.500 --> 00:04:12.139 a garzone, which is essentially a studio boy 00:04:12.139 --> 00:04:14.199 or an apprentice. In whose workshop? The workshop 00:04:14.199 --> 00:04:17.480 of Andrea del Verrocchio. And you have to understand, 00:04:17.699 --> 00:04:20.779 Verrocchio was not just a painter. He was the 00:04:20.779 --> 00:04:23.699 leading Florentine master known for his sculpture 00:04:23.699 --> 00:04:26.720 and for running this huge, almost industrial 00:04:26.720 --> 00:04:30.100 -scale operation. Leonardo spent seven crucial 00:04:30.100 --> 00:04:32.199 years there. And the sources are very clear. 00:04:32.240 --> 00:04:34.439 This wasn't just an art class. Far from it. This 00:04:34.439 --> 00:04:37.740 was vocational training. for a modern generalist. 00:04:37.819 --> 00:04:39.500 I mean, his seven years there gave him these 00:04:39.500 --> 00:04:42.639 incredibly broad technical and theoretical skills. 00:04:42.839 --> 00:04:45.420 Like what specifically? Well, drafting, sculpting, 00:04:45.420 --> 00:04:48.199 painting, obviously, but also chemistry for mixing 00:04:48.199 --> 00:04:51.019 pigments and mediums, metallurgy for bronze casting, 00:04:51.259 --> 00:04:53.899 mechanics for lifting these huge statues, plaster 00:04:53.899 --> 00:04:56.339 casting, woodworking. Wow. It was a hands -on 00:04:56.339 --> 00:04:58.740 technical institution. It set him up not just 00:04:58.740 --> 00:05:01.040 as an artist, but as an innovator who really 00:05:01.040 --> 00:05:03.439 understood how things were physically made. And 00:05:03.439 --> 00:05:06.470 his mastery showed almost instantly. Which brings 00:05:06.470 --> 00:05:09.350 us to that legendary story of the baptism of 00:05:09.350 --> 00:05:12.689 Christ. Ah, yes. Vasari, the famed biographer, 00:05:12.709 --> 00:05:17.990 he recounts this. Around 1472, maybe 1475, Leonardo 00:05:17.990 --> 00:05:20.370 is still a young apprentice. He collaborates 00:05:20.370 --> 00:05:23.329 with Verrocchio on this painting. Leonardo's 00:05:23.329 --> 00:05:25.550 job was to paint one of the young angels holding 00:05:25.550 --> 00:05:29.410 Jesus' robe. And the result was... Staggering. 00:05:29.410 --> 00:05:32.550 It was. His angel was deemed so superior, so 00:05:32.550 --> 00:05:35.230 alive and advanced in its technique that Verrocchio 00:05:35.230 --> 00:05:37.769 allegedly became so disheartened that he vowed 00:05:37.769 --> 00:05:40.129 never to paint again. Now, that's probably apocryphal, 00:05:40.129 --> 00:05:42.470 right? I mean, Verrocchio was a very busy sculptor. 00:05:42.529 --> 00:05:45.250 It probably is, yes. But the anecdote tells us 00:05:45.250 --> 00:05:46.930 something really important about Leonardo's technique 00:05:46.930 --> 00:05:48.649 at the time. Which was his immediate embrace 00:05:48.649 --> 00:05:51.439 of innovation. Exactly. The majority of the baptism 00:05:51.439 --> 00:05:53.860 of Christ was painted using the older, fast -drying 00:05:53.860 --> 00:05:56.540 temper technique. Leonardo used the newer, richer, 00:05:56.660 --> 00:05:59.060 more luminous oil paints for his angel. This 00:05:59.060 --> 00:06:00.899 wasn't just better drawing. It was better material 00:06:00.899 --> 00:06:04.360 science. He instantly saw and utilized his superior 00:06:04.360 --> 00:06:07.180 medium to get a level of realism and glow that 00:06:07.180 --> 00:06:09.399 just, well, it superseded his master's work. 00:06:09.759 --> 00:06:11.980 And speaking of realism and technical superiority 00:06:11.980 --> 00:06:15.300 translating into massive commercial value, we 00:06:15.300 --> 00:06:18.459 have the bizarre and wonderful story of the Medusa 00:06:18.459 --> 00:06:21.500 shield. Oh, this is a perfect anecdote. It shows 00:06:21.500 --> 00:06:24.279 his dedication to psychological realism to dramatic 00:06:24.279 --> 00:06:27.879 effect. A local peasant brings a round wooden 00:06:27.879 --> 00:06:30.480 shield to Leonardo's father, asking for it to 00:06:30.480 --> 00:06:33.680 be painted. A simple job. A simple job. Sir Piero 00:06:33.680 --> 00:06:36.290 passes it to Leonardo. But instead of painting 00:06:36.290 --> 00:06:38.750 a standard decorative scene, Leonardo decides 00:06:38.750 --> 00:06:41.009 he wants to create something that would terrify 00:06:41.009 --> 00:06:43.250 the viewer. He didn't just paint a Gorgon from 00:06:43.250 --> 00:06:46.189 mythology. No, he painted a monster derived from 00:06:46.189 --> 00:06:49.550 his own mind. He painted a fire -breathing, terrifying 00:06:49.550 --> 00:06:52.870 composite creature. And it was so lifelike, so 00:06:52.870 --> 00:06:55.290 detailed in its terror, that when he finally 00:06:55.290 --> 00:06:58.050 unveiled it to his father, Sir Piero recoiled 00:06:58.050 --> 00:07:00.649 in shock. This was his first use of art as pure 00:07:00.649 --> 00:07:03.269 psychological shock. Absolutely. And Sir Piero, 00:07:03.350 --> 00:07:06.029 being a savvy businessman, recognized the genius 00:07:06.029 --> 00:07:08.350 and the commercial value. He did not give it 00:07:08.350 --> 00:07:10.509 back to the peasant. What did he do? He quietly 00:07:10.509 --> 00:07:12.930 bought the peasant a cheaper, different shield, 00:07:13.089 --> 00:07:15.730 and then sold Leonardo's original creation to 00:07:15.730 --> 00:07:19.490 a Florentine art dealer for 100 ducats. 100 ducats. 00:07:19.509 --> 00:07:22.129 That was an enormous sum at the time. I mean, 00:07:22.129 --> 00:07:25.259 that's years of a skilled laborer's wages. It 00:07:25.259 --> 00:07:27.699 confirmed his commercial appeal early on. He 00:07:27.699 --> 00:07:30.779 could generate fear, wonder, fascination, and 00:07:30.779 --> 00:07:33.399 that translated directly into high monetary value. 00:07:33.720 --> 00:07:35.899 He was a recognized master in the Guild of St. 00:07:35.980 --> 00:07:38.639 Luke by age 20. And yet, despite all the success, 00:07:38.759 --> 00:07:40.819 despite major commissions in Florence, like the 00:07:40.819 --> 00:07:43.699 uncompleted Adoration of the Magi, he just ups 00:07:43.699 --> 00:07:46.819 and leaves around 1482. He moves to Milan. He 00:07:46.819 --> 00:07:49.939 does. And this move to Milan is perhaps the greatest 00:07:49.939 --> 00:07:53.009 indicator of his true interests. He wasn't looking 00:07:53.009 --> 00:07:54.829 for work as a painter. He was applying for a 00:07:54.829 --> 00:07:57.009 job as a defense contractor. That's exactly right. 00:07:57.129 --> 00:07:59.629 The letter he wrote to Ludovico Sforza, the Duke 00:07:59.629 --> 00:08:02.750 of Milan, is the true aha moment for understanding 00:08:02.750 --> 00:08:05.250 this whole paradox. In the same as letter, he 00:08:05.250 --> 00:08:07.550 lists 10 points detailing his abilities. And 00:08:07.550 --> 00:08:09.649 what's on the list? The first nine points relate 00:08:09.649 --> 00:08:12.870 entirely to engineering, weapon design, military 00:08:12.870 --> 00:08:14.910 architecture, and hydraulics. So he's talking 00:08:14.910 --> 00:08:18.389 about bridges and cannons. Yes. He details how 00:08:18.389 --> 00:08:21.100 he could build lightweight bridges. Design cannons 00:08:21.100 --> 00:08:23.899 that fired unusual projectiles, create armored 00:08:23.899 --> 00:08:26.480 fighting vehicles, use hydraulic principles for 00:08:26.480 --> 00:08:30.079 siege warfare. All military tech. And the painting, 00:08:30.259 --> 00:08:32.399 where does that come in? It's relegated to point 00:08:32.399 --> 00:08:35.659 number 10. He writes, I can also carry out work 00:08:35.659 --> 00:08:38.580 in sculpture. And in painting, I can do everything 00:08:38.580 --> 00:08:41.539 possible, as well as any other whoever he may 00:08:41.539 --> 00:08:44.700 be. So he positions painting almost as a side 00:08:44.700 --> 00:08:47.899 skill, an optional extra. He saw himself, first 00:08:47.899 --> 00:08:50.679 and foremost, as an engineer and military expert. 00:08:51.139 --> 00:08:53.259 And he even brought a musical instrument shaped 00:08:53.259 --> 00:08:56.320 like a horse's head made out of silver just to 00:08:56.320 --> 00:08:59.019 showcase his flair for multidisciplinary craftsmanship 00:08:59.019 --> 00:09:01.879 right in the job interview. And it worked. Sforza 00:09:01.879 --> 00:09:04.259 hired him. He was hired for his technical knowledge. 00:09:04.539 --> 00:09:06.980 And that kicked off his first Milanese period. 00:09:07.610 --> 00:09:09.809 This period, however, did still produce some 00:09:09.809 --> 00:09:11.909 absolute masterpieces. Right, like the Virgin 00:09:11.909 --> 00:09:14.309 of the Rocks. Yes, commissioned for the confraternity 00:09:14.309 --> 00:09:16.809 of the Immaculate Conception. That painting is 00:09:16.809 --> 00:09:18.330 groundbreaking because of the way he handles 00:09:18.330 --> 00:09:20.659 the figures and the environment. It has this 00:09:20.659 --> 00:09:23.980 beautiful, almost ethereal quality. It's so atmospheric. 00:09:24.279 --> 00:09:26.980 It does. He places the Madonna and the infants, 00:09:27.139 --> 00:09:29.980 Jesus and John the Baptist, a subject known as 00:09:29.980 --> 00:09:32.039 the apocryphal meeting. It's not explicitly in 00:09:32.039 --> 00:09:35.019 the Bible in this strange, tumbling, almost lunar 00:09:35.019 --> 00:09:37.379 landscape. It's filled with dark grottos and 00:09:37.379 --> 00:09:40.179 strange flora. And the light is incredible. He 00:09:40.179 --> 00:09:43.179 uses light and shadow to create this unified 00:09:43.179 --> 00:09:46.279 emotional field. The figures just emerge from 00:09:46.279 --> 00:09:49.139 the shadows, bathed in this soft internal glow. 00:09:49.629 --> 00:09:51.850 It demonstrates an early mastery of atmospheric 00:09:51.850 --> 00:09:54.929 depths that just moves far beyond the stiff linearity 00:09:54.929 --> 00:09:57.090 of his predecessors. Then you have The Lady with 00:09:57.090 --> 00:09:59.690 an Ermine, a portrait that introduces dynamic 00:09:59.690 --> 00:10:02.450 movement into what was, until then, a pretty 00:10:02.450 --> 00:10:05.090 static art form. A profound shift in portraiture. 00:10:05.129 --> 00:10:07.590 This is a painting of Cecilia Gallerani, Sforza's 00:10:07.590 --> 00:10:10.500 young mistress. And previously... Portraits were 00:10:10.500 --> 00:10:13.220 often very stiff, formal profiles. You're just 00:10:13.220 --> 00:10:16.019 looking off to the side. Exactly. But here, Cecilia's 00:10:16.019 --> 00:10:18.360 head is turned at an angle that contrasts with 00:10:18.360 --> 00:10:20.740 her torso. It suggests a sudden movement or a 00:10:20.740 --> 00:10:22.879 reaction. She looks as if she just heard something 00:10:22.879 --> 00:10:24.620 off canvas. But it's a psychological moment. 00:10:24.840 --> 00:10:27.840 It is. And the ermine she's holding is also significant. 00:10:28.200 --> 00:10:30.659 It could be a pun on her name. The Greek word 00:10:30.659 --> 00:10:33.960 gali means ermine or weasel. Or it could relate 00:10:33.960 --> 00:10:36.960 to Sforz's prestigious Order of the Ermine, which 00:10:36.960 --> 00:10:40.429 signaled virtue and purity. The innovation is 00:10:40.429 --> 00:10:42.909 that introduction of a narrative, a moment in 00:10:42.909 --> 00:10:45.570 time. And all of that artistic triumph in Milan 00:10:45.570 --> 00:10:48.629 was meant to culminate in this one massive project, 00:10:48.909 --> 00:10:51.809 the Sforza horse, the Gran Cavallo. The Gran 00:10:51.809 --> 00:10:54.409 Cavallo perfectly encapsulates the ambition and, 00:10:54.450 --> 00:10:57.090 well, the disappointment of his Milanese service. 00:10:57.629 --> 00:11:00.009 Sforza commissioned a massive equestrian monument 00:11:00.009 --> 00:11:02.750 for his father, Francesco Sforza. And Leonardo 00:11:02.750 --> 00:11:05.070 actually built a model, right? He did. He completed 00:11:05.070 --> 00:11:07.899 a 24 -foot tall clay model. It was widely admired. 00:11:08.100 --> 00:11:09.740 If it had been cast in bronze, it would have 00:11:09.740 --> 00:11:11.720 been the largest equestrian statue in history, 00:11:11.899 --> 00:11:14.559 far surpassing works like Donatello's Gattamelata. 00:11:14.759 --> 00:11:17.519 But the irony strikes again. The engineer loses 00:11:17.519 --> 00:11:19.860 his artistic monument because of a military need. 00:11:20.100 --> 00:11:24.500 In 1494, history intervenes. Francis King Charles 00:11:24.500 --> 00:11:27.879 VIII invades Italy, and Ludovico Sforza desperately 00:11:27.879 --> 00:11:30.929 needs to defend the city. The 70 tons of bronze 00:11:30.929 --> 00:11:33.029 that Leonardo had reserved for casting the horse 00:11:33.029 --> 00:11:35.850 were diverted. To make cannons. To manufacture 00:11:35.850 --> 00:11:38.370 cannons. The huge clay model was left exposed 00:11:38.370 --> 00:11:40.490 to the elements, and years later it was used 00:11:40.490 --> 00:11:42.909 for target practice by French soldiers. It just 00:11:42.909 --> 00:11:45.629 fell into ruin. His greatest artistic sculpture 00:11:45.629 --> 00:11:48.470 was sacrificed for the war machines he was hired 00:11:48.470 --> 00:11:50.649 to design in the first place. A truly frustrating 00:11:50.649 --> 00:11:53.899 cycle. A perfect example of the paradox. Okay, 00:11:53.940 --> 00:11:56.679 moving into our second major phase, we look at 00:11:56.679 --> 00:11:59.480 how Leonardo captured emotion and revolutionized 00:11:59.480 --> 00:12:02.259 painting technique, often leaving this enduring 00:12:02.259 --> 00:12:05.379 mystery behind the canvas. Let's start with what 00:12:05.379 --> 00:12:08.159 has become the most iconic, psychologically charged 00:12:08.159 --> 00:12:11.960 religious painting ever, The Last Supper. After 00:12:11.960 --> 00:12:13.720 the failed horse project, Leonardo dedicated 00:12:13.720 --> 00:12:16.480 himself to this commission. It's in the refectory 00:12:16.480 --> 00:12:18.820 of the Convento Santa Maria del Vigrazi in Milan. 00:12:19.320 --> 00:12:23.399 He painted it from about 1495 to 1498, and he 00:12:23.399 --> 00:12:26.279 chose the most explosive, the most dramatic moment 00:12:26.279 --> 00:12:28.720 possible. The moment of betrayal. The immediate 00:12:28.720 --> 00:12:30.779 reaction of the disciples right after Jesus says, 00:12:30.919 --> 00:12:32.899 one of you will betray me. And the genius of 00:12:32.899 --> 00:12:35.539 the work is how he manages to capture 12 separate, 00:12:35.639 --> 00:12:38.500 distinct psychological reactions. He groups them 00:12:38.500 --> 00:12:42.220 into four triads of three. It's an absolute masterclass 00:12:42.220 --> 00:12:46.120 in emotion, gesture, and characterization. I 00:12:46.120 --> 00:12:48.590 mean, you see... Disbelief, you see anger, confusion, 00:12:48.889 --> 00:12:51.909 horror, all radiating from these groups and all 00:12:51.909 --> 00:12:54.289 of it pointing back to this calm, isolated figure 00:12:54.289 --> 00:12:57.009 of Christ at the center. The emotional intensity 00:12:57.009 --> 00:13:00.590 is just, it's unprecedented. And he did his research. 00:13:00.649 --> 00:13:02.990 He didn't just imagine these faces. Not at all. 00:13:03.009 --> 00:13:05.169 He spent hours simply observing people in the 00:13:05.169 --> 00:13:07.450 streets, looking for faces that could represent 00:13:07.450 --> 00:13:11.889 various character types from nobility to treachery. 00:13:12.080 --> 00:13:14.899 That deep, almost clinical study of human emotion 00:13:14.899 --> 00:13:17.700 physiognomy is so key to his artistic method. 00:13:18.019 --> 00:13:20.580 But my favorite anecdote from this period involves 00:13:20.580 --> 00:13:23.000 a convent prior who clearly did not understand 00:13:23.000 --> 00:13:25.139 the creative process. Ah, yes, the poor prior. 00:13:25.360 --> 00:13:27.600 The writer Matteo Bandello, who actually observed 00:13:27.600 --> 00:13:30.120 Leonardo at work, noted that Leonardo's process 00:13:30.120 --> 00:13:33.039 was erratic. Not a 9 -to -5 job. Definitely not. 00:13:33.559 --> 00:13:36.480 Some days he would paint continuously from sunrise 00:13:36.480 --> 00:13:38.700 to sunset, but then other days he would just 00:13:38.700 --> 00:13:40.620 stand there and stare at the work for hours, 00:13:40.799 --> 00:13:43.139 maybe add a single brush stroke or sometimes 00:13:43.139 --> 00:13:46.159 not paint at all for three or four days. And 00:13:46.159 --> 00:13:48.460 the prior, who thought painting should be a steady 00:13:48.460 --> 00:13:52.120 job, hounded Leonardo mercilessly. And Leonardo 00:13:52.120 --> 00:13:54.679 being Leonardo turned this bureaucratic irritation 00:13:54.679 --> 00:13:58.379 into a pretty serious threat. He did. He sought 00:13:58.379 --> 00:14:00.620 the Duke's intervention to stop the prior's harassment. 00:14:00.940 --> 00:14:03.059 He explained that he was troubled over finding 00:14:03.059 --> 00:14:06.139 the perfect face for Christ and equally the perfect 00:14:06.139 --> 00:14:08.679 face for the traitor Judas. And then he dropped 00:14:08.679 --> 00:14:11.080 the bombshell. He told the Duke that if he could 00:14:11.080 --> 00:14:13.340 not find a suitable model for the villain soon, 00:14:13.600 --> 00:14:15.799 he would be forced to use the face of the prior. 00:14:15.980 --> 00:14:19.259 Huh. I love that. And according to Vasari, that 00:14:19.259 --> 00:14:21.639 little threat secured him peace to work on the 00:14:21.639 --> 00:14:23.769 mural for the remainder of the commission. That 00:14:23.769 --> 00:14:26.049 detail about the non -continuous painting and 00:14:26.049 --> 00:14:29.210 his desire for perfect realism, it also hints 00:14:29.210 --> 00:14:31.870 at the profound tragedy of his choice of medium 00:14:31.870 --> 00:14:34.730 for The Last Supper. It is perhaps the biggest 00:14:34.730 --> 00:14:37.230 artistic miscalculation of his entire career. 00:14:37.490 --> 00:14:41.029 He needed a medium that allowed for slow, deliberate 00:14:41.029 --> 00:14:44.610 blending and correction. True fresco, painting 00:14:44.610 --> 00:14:46.750 on wet plaster doesn't allow for that. You have 00:14:46.750 --> 00:14:49.559 to work fast. So he experimented. He did. He 00:14:49.559 --> 00:14:51.639 used tempera mixed with oil on a dry plaster 00:14:51.639 --> 00:14:53.840 surface that he'd prepared with gesso and pitch. 00:14:54.100 --> 00:14:56.799 But this technique was completely unstable, especially 00:14:56.799 --> 00:14:58.919 in Milan's humid climate. And the consequence 00:14:58.919 --> 00:15:01.539 was a disaster. A profound tragedy, absolutely. 00:15:01.840 --> 00:15:03.940 The sources confirmed that within 100 years, 00:15:04.159 --> 00:15:06.580 the painting was already described by one viewer 00:15:06.580 --> 00:15:09.659 as completely ruined. The paint was just flaking 00:15:09.659 --> 00:15:11.980 off the wall. And yet it's still the most reproduced 00:15:11.980 --> 00:15:14.000 religious painting ever. Which just speaks to 00:15:14.000 --> 00:15:15.980 the sheer power and perfection of the underlying 00:15:15.980 --> 00:15:19.279 composition. It's that good. Speaking of achieving 00:15:19.279 --> 00:15:22.899 nuanced, perfect effects, this brings us to Leonardo's 00:15:22.899 --> 00:15:25.799 key painting innovation. It's the signature technique 00:15:25.799 --> 00:15:29.659 you see on his most famous work, sfumato. Sfumato. 00:15:29.799 --> 00:15:32.940 It literally translates from the Italian as smoky 00:15:32.940 --> 00:15:36.059 or like smoke. And it's a technique of creating 00:15:36.059 --> 00:15:39.179 this subtle, almost imperceptible gradation of 00:15:39.179 --> 00:15:42.789 tone or shading. It allows colors and tones to 00:15:42.789 --> 00:15:45.230 blend into one another without any distinct outlines. 00:15:45.570 --> 00:15:48.149 So it softens the edges. It softens edges and 00:15:48.149 --> 00:15:51.110 creates an elusive, misty quality. It's not just 00:15:51.110 --> 00:15:53.149 shading, though. It's really an optical illusion 00:15:53.149 --> 00:15:55.970 designed to trick the eye. And it perfectly complements 00:15:55.970 --> 00:15:58.549 his study of physiognomy. Exactly. His lifelong 00:15:58.549 --> 00:16:01.070 study of how the human face registers fleeting, 00:16:01.070 --> 00:16:04.230 complex emotion. By blurring the lines around 00:16:04.230 --> 00:16:06.690 the eyes and the mouth, he leaves the exact nature 00:16:06.690 --> 00:16:09.370 of the subject's expression ambiguous. It forces 00:16:09.370 --> 00:16:11.789 your eye and your brain to constantly re -evaluate 00:16:11.789 --> 00:16:13.490 what you're seeing. And all of this converges 00:16:13.490 --> 00:16:15.830 on the Mona Lisa. The Mona Lisa, or La Gioconda, 00:16:15.990 --> 00:16:18.110 is the absolute culmination of this technique. 00:16:18.450 --> 00:16:20.750 Its status as the world's most famous individual 00:16:20.750 --> 00:16:23.789 painting rests entirely on that famous, elusive, 00:16:23.809 --> 00:16:26.649 and mysterious smile. And that mystery is fumato. 00:16:26.870 --> 00:16:30.700 It's pure fumato. The subtle, deeply shadowed 00:16:30.700 --> 00:16:32.740 corners of the mouth and the eyes prevent you, 00:16:33.000 --> 00:16:36.220 the viewer, from ever being able to definitively 00:16:36.220 --> 00:16:39.259 say whether she is smiling or not. Right. If 00:16:39.259 --> 00:16:41.519 you stare at her eyes, the smile seems to vanish, 00:16:41.580 --> 00:16:43.720 and if you stare at her mouth, it reappears. 00:16:44.059 --> 00:16:46.519 It's a kinetic painting, even though it's completely 00:16:46.519 --> 00:16:49.120 static. And beyond that psychological effect, 00:16:49.320 --> 00:16:51.919 the painting is a technical marvel. The dress 00:16:51.919 --> 00:16:54.269 is unadorned. which ensures all your attention 00:16:54.269 --> 00:16:57.269 is focused on the hands and the face. The background 00:16:57.269 --> 00:17:01.350 is this dramatic, fluctuating, desolate, almost 00:17:01.350 --> 00:17:04.450 alien landscape with winding paths and water. 00:17:04.609 --> 00:17:06.990 And the brush strokes are invisible. That's the 00:17:06.990 --> 00:17:09.069 crucial part. The sources point out the extreme 00:17:09.069 --> 00:17:11.769 smoothness of the application of oils. They're 00:17:11.769 --> 00:17:13.869 blended so perfectly that the brush strokes are 00:17:13.869 --> 00:17:17.140 virtually invisible. Vasari, in awe, said the 00:17:17.140 --> 00:17:19.299 quality of the painting would make even the most 00:17:19.299 --> 00:17:22.460 confident master despair and lose heart. Yet 00:17:22.460 --> 00:17:24.759 perhaps the greatest irony of his entire painting 00:17:24.759 --> 00:17:26.880 career is that the most famous work in the world 00:17:26.880 --> 00:17:29.160 may have been left technically unfinished due 00:17:29.160 --> 00:17:31.500 to a physical disability. This is one of the 00:17:31.500 --> 00:17:33.539 most important biographical details confirmed 00:17:33.539 --> 00:17:36.519 by the sources. Leonardo kept working on the 00:17:36.519 --> 00:17:39.160 Mona Lisa for years. He carried it with him to 00:17:39.160 --> 00:17:42.420 France. But crucially, we have a medical record 00:17:42.420 --> 00:17:45.420 from October 1517 confirming a paralysis of his 00:17:45.420 --> 00:17:48.700 right hand at age 65. And this is why he stopped 00:17:48.700 --> 00:17:51.480 painting major commissions. The sources explicitly 00:17:51.480 --> 00:17:54.680 suggest this is the reason. It's why pieces like 00:17:54.680 --> 00:17:56.420 the Mona Lisa were left technically incomplete. 00:17:57.279 --> 00:17:59.460 While he remained perfected with his left hand 00:17:59.460 --> 00:18:02.079 for writing, the fine motor skills required for 00:18:02.079 --> 00:18:04.799 that invisible blend, that perfect sfumato, they 00:18:04.799 --> 00:18:06.740 were compromised. From the meticulous perfection 00:18:06.740 --> 00:18:09.759 of the Mona Lisa, we pivot to the sheer, magnificent 00:18:09.759 --> 00:18:12.099 mess of his mind as captured in his drawings. 00:18:12.599 --> 00:18:14.900 These journals aren't just art. They're the complete 00:18:14.900 --> 00:18:17.509 visual index of his intellectual life. He was 00:18:17.509 --> 00:18:19.910 a prolific draftsman to an almost unbelievable 00:18:19.910 --> 00:18:23.789 degree. I mean, he amassed a staggering 13 ,000 00:18:23.789 --> 00:18:26.329 pages of surviving notes and drawings. And just 00:18:26.329 --> 00:18:28.759 think how much must have been lost. Exactly. 00:18:28.839 --> 00:18:32.160 The total volume of his recorded thought is unimaginable. 00:18:32.180 --> 00:18:34.599 And these journals contain everything from grocery 00:18:34.599 --> 00:18:37.940 lists to detailed designs for war machines, philosophy, 00:18:38.380 --> 00:18:41.160 optical studies, and of course, anatomy. And 00:18:41.160 --> 00:18:43.759 among these thousands of pages, we find iconic 00:18:43.759 --> 00:18:47.019 works that are known globally. Yes. The instantly 00:18:47.019 --> 00:18:50.170 recognizable Vitruvian Man. which is a study 00:18:50.170 --> 00:18:52.390 of human proportions based on the Roman architect 00:18:52.390 --> 00:18:56.410 Vitruvius' theories and his thousands of detailed 00:18:56.410 --> 00:18:58.910 anatomical studies, including the scientific 00:18:58.910 --> 00:19:01.460 drawing of a fetus in utero. These aren't just 00:19:01.460 --> 00:19:03.880 art or science, are they? They're a fusion. They're 00:19:03.880 --> 00:19:06.660 the fusion of both disciplines. He used the perfection 00:19:06.660 --> 00:19:09.380 of artistic technique to serve the accuracy of 00:19:09.380 --> 00:19:12.180 scientific observation. And sometimes that observational 00:19:12.180 --> 00:19:15.299 impulse took a very dark, detached turn, which 00:19:15.299 --> 00:19:17.619 is exemplified by that macabre sketch of the 00:19:17.619 --> 00:19:19.960 hanged man. That sketch is a chilling illustration 00:19:19.960 --> 00:19:23.839 of his purely clinical eye. In 1479, after the 00:19:23.839 --> 00:19:26.480 Pazzi conspiracy, an attempt by the Pazzi family 00:19:26.480 --> 00:19:29.099 to assassinate Lorenzo de' Medici, a man named 00:19:29.099 --> 00:19:31.400 Bernardo Barancelli was hanged in Florence. And 00:19:31.400 --> 00:19:33.960 Leonardo went to watch. He went and meticulously 00:19:33.960 --> 00:19:37.099 documented the body. He recorded every detail 00:19:37.099 --> 00:19:39.480 of the man's appearance, including the precise 00:19:39.480 --> 00:19:41.799 colors and condition of the robes the condemned 00:19:41.799 --> 00:19:45.390 man wore when he died. It was pure, detached, 00:19:45.650 --> 00:19:48.109 scientific record keeping. He was treating a 00:19:48.109 --> 00:19:50.769 fresh corpse as just another object to be drawn 00:19:50.769 --> 00:19:53.670 and cataloged. That cold, clinical eye he used 00:19:53.670 --> 00:19:56.789 for artistic realism, even when observing a hanged 00:19:56.789 --> 00:19:59.410 criminal, leads us directly into the core of 00:19:59.410 --> 00:20:02.809 our paradox. Leonardo, the unrecognized scientist 00:20:02.809 --> 00:20:05.509 and engineer. This is the part of the deep dive 00:20:05.509 --> 00:20:07.690 that requires the most attention, because while 00:20:07.690 --> 00:20:09.950 the world worships the painter, the scientist 00:20:09.950 --> 00:20:12.500 was truly centuries ahead of his time. If we 00:20:12.500 --> 00:20:14.940 look at his scientific methodology, one characteristic 00:20:14.940 --> 00:20:17.859 is paramount. His approach was purely empirical 00:20:17.859 --> 00:20:20.180 and observational. He believed only in what he 00:20:20.180 --> 00:20:22.960 could see, describe and accurately depict. He 00:20:22.960 --> 00:20:26.339 was driven by a burning desire to, well, to reverse 00:20:26.339 --> 00:20:28.740 engineer creation. And this is where his earlier 00:20:28.740 --> 00:20:31.160 lack of formal education becomes a major liability 00:20:31.160 --> 00:20:34.180 that stifled the dissemination of his work. Precisely. 00:20:34.460 --> 00:20:37.559 Because he lacked formal education in Latin and 00:20:37.559 --> 00:20:39.880 advanced mathematics, the requisite languages 00:20:39.880 --> 00:20:41.799 for scholarly communication in the Renaissance, 00:20:42.140 --> 00:20:45.220 his scientific work was largely dismissed or 00:20:45.220 --> 00:20:47.400 simply unreadable by contemporary academics. 00:20:47.740 --> 00:20:50.059 They judged the language of the messenger, not 00:20:50.059 --> 00:20:52.160 the brilliance of the message. And the sheer 00:20:52.160 --> 00:20:54.599 magnitude of his intellectual leap is confirmed 00:20:54.599 --> 00:20:57.119 by this stunning statement found in his notes. 00:20:57.359 --> 00:21:01.700 Il sole non si move. The sun does not move. That 00:21:01.700 --> 00:21:05.039 is profound. He was anticipating the heliocentric 00:21:05.039 --> 00:21:07.519 model, which wouldn't gain wide acceptance until 00:21:07.519 --> 00:21:10.460 decades after Copernicus's death and decades 00:21:10.460 --> 00:21:13.380 after Leonardo wrote that down. It confirms he 00:21:13.380 --> 00:21:15.259 was thinking radically beyond the established 00:21:15.259 --> 00:21:19.240 Ptolemaic Earth -centric view. But nowhere, nowhere 00:21:19.240 --> 00:21:21.660 was his scientific genius more revolutionary 00:21:21.660 --> 00:21:24.259 than in anatomy. Let's just contextualize this 00:21:24.259 --> 00:21:26.180 for you listening. What was the accepted state 00:21:26.180 --> 00:21:29.210 of medical knowledge in Europe around 1500? Medicine 00:21:29.210 --> 00:21:31.549 was still overwhelmingly dominated by Galenic 00:21:31.549 --> 00:21:33.950 theory. This was based on the writings of Galen, 00:21:34.029 --> 00:21:36.609 a Roman physician who lived over 1 ,300 years 00:21:36.609 --> 00:21:39.829 earlier. And Galen's work was based largely on 00:21:39.829 --> 00:21:42.109 the dissection of animals, like pigs and monkeys, 00:21:42.269 --> 00:21:44.970 because human dissection was often taboo. So 00:21:44.970 --> 00:21:47.450 it was based on faulty data, and the prevailing 00:21:47.450 --> 00:21:50.190 theory was the four humors. Yes, the system of 00:21:50.190 --> 00:21:53.210 the four humors, blood, phlegm, yellow bile, 00:21:53.349 --> 00:21:56.509 and black bile. Disease was seen as an imbalance 00:21:56.509 --> 00:21:59.630 of these. So when Leonardo began dissecting human 00:21:59.630 --> 00:22:01.829 corpses, he wasn't just drawing. He was tearing 00:22:01.829 --> 00:22:04.430 down the foundations of 1 ,300 years of accepted 00:22:04.430 --> 00:22:06.809 medical practice. Absolutely. He was granted 00:22:06.809 --> 00:22:09.009 permission to dissect human corpses at hospitals 00:22:09.009 --> 00:22:12.329 in Florence, Milan, and Rome, and he ultimately 00:22:12.329 --> 00:22:15.549 examined around 30 bodies in great detail. He 00:22:15.549 --> 00:22:17.289 even collaborated with the anatomy professor 00:22:17.289 --> 00:22:20.990 Marcantonio della Torre around 1510. His goal 00:22:20.990 --> 00:22:23.329 was to publish an anatomical treatise. And the 00:22:23.329 --> 00:22:25.710 scale of his output is astounding, even if it 00:22:25.710 --> 00:22:29.559 was never published. He generated over 240 incredibly 00:22:29.559 --> 00:22:33.559 detailed drawings and wrote roughly 13 ,000 words 00:22:33.559 --> 00:22:36.359 toward this treatise. These weren't sketches. 00:22:36.500 --> 00:22:39.019 These were blueprints of the human body. They 00:22:39.019 --> 00:22:41.460 provided a view of internal organs, muscles, 00:22:41.599 --> 00:22:44.259 and bones that had never before been accurately 00:22:44.259 --> 00:22:46.519 rendered. Okay, let's dive into the groundbreaking, 00:22:46.720 --> 00:22:48.900 crucial medical discoveries he made that went 00:22:48.900 --> 00:22:51.779 completely unrecognized for centuries. Well, 00:22:51.799 --> 00:22:54.339 he fundamentally redefined several branches of 00:22:54.339 --> 00:22:56.980 medicine. For instance, he prefigured the entire 00:22:56.980 --> 00:22:59.440 field of biomechanics by studying the body as 00:22:59.440 --> 00:23:02.180 a machine. A machine of levers and pulleys? Exactly. 00:23:02.279 --> 00:23:05.000 He analyzed the skeletal structure not just as 00:23:05.000 --> 00:23:07.940 a static frame, but as a system of levers, pulleys, 00:23:07.940 --> 00:23:10.720 and forces. He studied the forces exerted by 00:23:10.720 --> 00:23:12.740 specific muscles in movement. And what about 00:23:12.740 --> 00:23:15.039 specific diseases? He was able to identify them. 00:23:15.180 --> 00:23:17.500 This is where he truly leaps ahead. He was the 00:23:17.500 --> 00:23:20.000 first person to accurately define both atherosclerosis, 00:23:20.160 --> 00:23:22.720 the hardening and narrowing of arteries, due 00:23:22.720 --> 00:23:25.240 to plaque buildup and liver cirrhosis. You have 00:23:25.240 --> 00:23:27.839 to remember, in the 1500s, illness was understood 00:23:27.839 --> 00:23:31.220 through this vague imbalance of humors. And Leonardo 00:23:31.220 --> 00:23:33.640 was observing and accurately documenting the 00:23:33.640 --> 00:23:36.740 pathology of specific organ failures. He was 00:23:36.740 --> 00:23:38.859 recognizing the physical changes that defined 00:23:38.859 --> 00:23:41.880 a disease, not just the symptoms. He also directly 00:23:41.880 --> 00:23:44.359 refuted the ancient wisdom of Galen and the whole 00:23:44.359 --> 00:23:46.960 humor theory. He did. Galenic medicine believed 00:23:46.960 --> 00:23:50.220 that the cerebral spaces and major organs contained 00:23:50.220 --> 00:23:53.160 these theoretical humors. Leonardo's detailed 00:23:53.160 --> 00:23:56.039 documentation, based on actual human dissection, 00:23:56.259 --> 00:23:58.799 proved that the humors were not contained in 00:23:58.799 --> 00:24:01.140 the cerebral ventricles or major organs as they 00:24:01.140 --> 00:24:04.500 believed. He established the true structure of 00:24:04.500 --> 00:24:06.619 the cerebral ventricles. And that leads us to 00:24:06.619 --> 00:24:08.759 his experimental techniques, which are really 00:24:08.759 --> 00:24:10.960 the hallmark of modern science. He didn't just 00:24:10.960 --> 00:24:13.759 look. He built models to prove his concepts. 00:24:14.019 --> 00:24:16.079 His experimental ingenuity is just phenomenal. 00:24:16.279 --> 00:24:19.039 To map the true geometry of the cerebral ventricles, 00:24:19.099 --> 00:24:21.420 he wasn't satisfied with simple drawings. What 00:24:21.420 --> 00:24:24.319 did he do? He injected melted wax into the brain's 00:24:24.319 --> 00:24:27.059 internal cavities, the ventricles, and then allowed 00:24:27.059 --> 00:24:30.299 the wax to solidify. It created a perfect, exact, 00:24:30.519 --> 00:24:32.299 three -dimensional cast of those structures. 00:24:32.539 --> 00:24:35.279 So he could literally hold the internal architecture 00:24:35.279 --> 00:24:38.819 of the human brain in his hands. That's an enormous 00:24:38.819 --> 00:24:41.259 leap in visualization. His visualization married 00:24:41.259 --> 00:24:43.799 to proof. And he did the same thing with the 00:24:43.799 --> 00:24:46.039 circulatory system. He made the groundbreaking 00:24:46.039 --> 00:24:49.509 observation that the heart... define the circulatory 00:24:49.509 --> 00:24:52.230 system. So to study the aortic valve, which controls 00:24:52.230 --> 00:24:54.670 blood flow out of the heart, he built a working 00:24:54.670 --> 00:24:57.470 model. A model of an aorta. He constructed a 00:24:57.470 --> 00:25:00.730 transparent glass aorta and then used water mixed 00:25:00.730 --> 00:25:03.829 with grass seed to visually observe the circulation 00:25:03.829 --> 00:25:06.450 patterns as the water passed through the valve. 00:25:06.690 --> 00:25:09.349 He was using water flow and seed particles to 00:25:09.349 --> 00:25:11.710 replicate and study hemodynamics hundreds of 00:25:11.710 --> 00:25:14.289 years before anyone else. This is pure physics 00:25:14.289 --> 00:25:16.869 applied to biology. And that application of physics 00:25:16.869 --> 00:25:19.980 brings us to his engineering ingenuity. He's 00:25:19.980 --> 00:25:22.259 credited with producing the first form of modern 00:25:22.259 --> 00:25:25.079 technical drawing. He innovated the exploded 00:25:25.079 --> 00:25:27.400 view technique to represent complex internal 00:25:27.400 --> 00:25:30.440 components by showing them separated but aligned. 00:25:30.740 --> 00:25:33.079 A standard practice in engineering today. Absolutely. 00:25:33.160 --> 00:25:36.079 He generated over 5 ,000 pages of these precise 00:25:36.079 --> 00:25:38.799 technical designs in his codices. We often hear 00:25:38.799 --> 00:25:41.480 about his most fantastical ideas, the things 00:25:41.480 --> 00:25:43.579 that were truly impossible in the 15th century. 00:25:43.779 --> 00:25:46.710 The visionary designs, yes. He sketched several 00:25:46.710 --> 00:25:49.970 concepts for flying machines. One was the ornithopter, 00:25:50.049 --> 00:25:52.529 designed to mimic the flapping motion of a bird's 00:25:52.529 --> 00:25:55.450 wings. Another was the helical rotor, often called 00:25:55.450 --> 00:25:57.890 the aerial screw. The forerunner to the helicopter? 00:25:58.289 --> 00:26:00.569 The concept is similar, yes, a rapidly turning 00:26:00.569 --> 00:26:03.269 coil. But the sources note that while the principles 00:26:03.269 --> 00:26:05.690 were sound, the necessary materials science, 00:26:05.950 --> 00:26:08.900 the lightweight engines, the metallurgy... They 00:26:08.900 --> 00:26:11.740 were centuries away. But he also designed functional 00:26:11.740 --> 00:26:15.140 military and civil technology. Absolutely. He 00:26:15.140 --> 00:26:17.680 designed an armored fighting vehicle, a forerunner 00:26:17.680 --> 00:26:19.319 of the tank, which was powered by men pushing 00:26:19.319 --> 00:26:22.539 cranks. He designed complex hydraulic pumps and 00:26:22.539 --> 00:26:25.299 various reversible crank mechanisms. He even 00:26:25.299 --> 00:26:28.019 designed a steam cannon. And some very practical, 00:26:28.160 --> 00:26:30.859 unheralded inventions. Yes, things that likely 00:26:30.859 --> 00:26:33.240 entered manufacturing. without his name attached, 00:26:33.519 --> 00:26:36.140 an automated bobbin winder for textile production, 00:26:36.339 --> 00:26:39.079 for example, and a specialized machine for testing 00:26:39.079 --> 00:26:41.660 the tensile strength of wire. He wasn't just 00:26:41.660 --> 00:26:43.680 dreaming big. He was improving manufacturing 00:26:43.680 --> 00:26:46.619 efficiency. His civil and military engineering 00:26:46.619 --> 00:26:49.240 was highly sought after, especially when he was 00:26:49.240 --> 00:26:52.799 serving Cesare Borgia. In 1502, he was hired 00:26:52.799 --> 00:26:55.880 as Borgia's chief military engineer and architect. 00:26:56.240 --> 00:26:59.119 And he didn't just design machines. He mapped 00:26:59.119 --> 00:27:02.109 terrain strategically. He created these incredibly 00:27:02.109 --> 00:27:05.269 sophisticated, accurate town plans and strategic 00:27:05.269 --> 00:27:08.150 maps, like the famous plan of Imola. Which gave 00:27:08.150 --> 00:27:11.269 Borgia a comprehensive, modern, strategic overlay 00:27:11.269 --> 00:27:13.670 of the territory. It was reconnaissance elevated 00:27:13.670 --> 00:27:16.930 to an art form. Later, in Florence, he worked 00:27:16.930 --> 00:27:19.430 on a major infrastructure scheme with none other 00:27:19.430 --> 00:27:22.410 than Niccolo Machiavelli to divert the flow of 00:27:22.410 --> 00:27:24.430 the Arno River, though that project ultimately 00:27:24.430 --> 00:27:26.730 failed. Okay, now let's address the most jarring 00:27:26.730 --> 00:27:29.769 example of this whole paradox, the laws of friction. 00:27:30.200 --> 00:27:32.160 This is foundational physics that he wrote down 00:27:32.160 --> 00:27:34.900 in a notebook in 1493, only for the world to 00:27:34.900 --> 00:27:37.460 ignore it for 200 years. This is the ultimate 00:27:37.460 --> 00:27:40.079 example of lost intellectual capital. The study 00:27:40.079 --> 00:27:42.240 of friction, wear, and lubrication is called 00:27:42.240 --> 00:27:44.519 tribology, and it is fundamental to all mechanical 00:27:44.519 --> 00:27:46.799 engineering. You cannot build a reliable machine 00:27:46.799 --> 00:27:49.420 without understanding friction. Leonardo first 00:27:49.420 --> 00:27:51.400 articulated the core laws of sliding friction 00:27:51.400 --> 00:27:55.539 in 1493. So what conceptually did he figure out? 00:27:55.720 --> 00:27:59.710 He discovered two major laws. First, that the 00:27:59.710 --> 00:28:01.750 force of friction is proportional to the load 00:28:01.750 --> 00:28:04.190 pressing the two surfaces together. Simple enough. 00:28:04.589 --> 00:28:07.190 But second, and this is the counterintuitive 00:28:07.190 --> 00:28:09.789 part for his time, he realized that the friction 00:28:09.789 --> 00:28:12.210 force is largely independent of the apparent 00:28:12.210 --> 00:28:14.990 area of contact between the two surfaces. So 00:28:14.990 --> 00:28:17.490 if you have a heavy block, whether it's resting 00:28:17.490 --> 00:28:20.430 on its wide side or its narrow side, the force 00:28:20.430 --> 00:28:22.829 needed to slide it horizontally is the same. 00:28:23.029 --> 00:28:25.839 Exactly. It defies common sense. And it was a 00:28:25.839 --> 00:28:28.119 revolutionary insight that stemmed directly from 00:28:28.119 --> 00:28:30.400 his engineering design work and his attempt to 00:28:30.400 --> 00:28:33.200 prove that perpetual motion was impossible, which 00:28:33.200 --> 00:28:36.759 he also correctly dismissed. He provided detailed 00:28:36.759 --> 00:28:39.160 drawings and calculations. But because they were 00:28:39.160 --> 00:28:41.180 locked in his private notes, written in mirror 00:28:41.180 --> 00:28:43.779 script, they had zero impact on the progression 00:28:43.779 --> 00:28:46.119 of mechanics. 200 years later, they were independently 00:28:46.119 --> 00:28:49.559 rediscovered. Yes. The laws were independently 00:28:49.559 --> 00:28:53.579 rediscovered and codified in 1699 by a French 00:28:53.579 --> 00:28:56.880 physicist, Guillaume Amonton, whose name is usually 00:28:56.880 --> 00:29:00.380 associated with them today. Leonardo was retrospectively 00:29:00.380 --> 00:29:03.160 named the first of the men of tribology, but 00:29:03.160 --> 00:29:05.279 that recognition came hundreds of years too late 00:29:05.279 --> 00:29:07.200 to help the Renaissance. Just think about the 00:29:07.200 --> 00:29:09.880 entire epoch of the scientific revolution that 00:29:09.880 --> 00:29:11.720 could have been accelerated if that fundamental 00:29:11.720 --> 00:29:13.779 knowledge of mechanics had been available in 00:29:13.779 --> 00:29:16.599 1500. It's staggering to contemplate. Moving 00:29:16.599 --> 00:29:19.269 on to section four. The final years of Leonardo's 00:29:19.269 --> 00:29:22.089 life saw him transition from the constantly hustling, 00:29:22.089 --> 00:29:24.829 struggling court artist and engineer, who was 00:29:24.829 --> 00:29:27.410 often paid late into a life of comfortable, internationally 00:29:27.410 --> 00:29:30.730 recognized genius. That's right. After the French 00:29:30.730 --> 00:29:33.910 overthrew Ludvico Sforza in 1500, Leonardo fled 00:29:33.910 --> 00:29:36.710 Milan. And after a brief stint serving Cesar 00:29:36.710 --> 00:29:41.099 Borgia, his final major move came in 1516. He 00:29:41.099 --> 00:29:43.000 was invited to France by the young King Francis 00:29:43.000 --> 00:29:45.980 I. Who was a great admirer. A huge admirer. Francis 00:29:45.980 --> 00:29:48.680 I offered him the use of the manor house Colsluset 00:29:48.680 --> 00:29:51.000 near the royal residence. And the patronage was 00:29:51.000 --> 00:29:53.160 substantial. He was finally rewarded appropriately. 00:29:53.380 --> 00:29:55.640 He was given a massive pension, right? An enormous 00:29:55.640 --> 00:29:58.980 pension, 10 ,000 scudi annually. It made him 00:29:58.980 --> 00:30:01.799 immensely wealthy and secure. And Francis I treated 00:30:01.799 --> 00:30:03.779 him not just as an employee, but as a friend, 00:30:03.880 --> 00:30:06.339 a national trophy. He said he considered himself 00:30:06.339 --> 00:30:08.460 honored to converse with such a great man and 00:30:08.460 --> 00:30:11.150 frequently visited him at Colsluset. That close 00:30:11.150 --> 00:30:14.009 relationship led to one last major demonstration 00:30:14.009 --> 00:30:16.769 of his engineering flair, didn't it? The mechanical 00:30:16.769 --> 00:30:20.109 lion. It's a spectacular tale. It fuses art, 00:30:20.230 --> 00:30:23.650 spectacle, and mechanics. For a pageant honoring 00:30:23.650 --> 00:30:26.630 Francis I, Leonardo engineered a complex mechanical 00:30:26.630 --> 00:30:29.769 lion. The lion walked toward the king. On its 00:30:29.769 --> 00:30:32.950 own. On its own. And upon being struck by a wand, 00:30:33.130 --> 00:30:35.309 its chest cavity opened to reveal a cluster of 00:30:35.309 --> 00:30:37.450 fleur -de -lis, the symbol of the French monarchy. 00:30:37.730 --> 00:30:39.769 It was engineering used for pure theatrical. 00:30:39.920 --> 00:30:42.259 delight. It's fascinating how his public life 00:30:42.259 --> 00:30:44.880 was full of spectacle and patronage, yet his 00:30:44.880 --> 00:30:47.140 personal life remains largely veiled in ambiguity. 00:30:47.539 --> 00:30:49.839 We only really glimpse it through his relationships 00:30:49.839 --> 00:30:52.519 with the students. His voluminous notebooks scarcely 00:30:52.519 --> 00:30:55.279 touch on his private life, but we do know he 00:30:55.279 --> 00:30:58.079 had these intense lifelong relationships with 00:30:58.079 --> 00:31:00.839 his pupils. Francesco Melzi was his favorite 00:31:00.839 --> 00:31:03.279 student and the principal heir to his artistic 00:31:03.279 --> 00:31:06.279 and scientific legacy. He treated him like a 00:31:06.279 --> 00:31:08.420 son. And Melzi was the one who tried to organize 00:31:08.420 --> 00:31:11.640 all the notes after he died. He was. He collected 00:31:11.640 --> 00:31:14.559 and organized and treasured the thousands of 00:31:14.559 --> 00:31:16.900 scattered pages after Leonardo's death. And then 00:31:16.900 --> 00:31:19.059 there was Salai. The sources portray him as a 00:31:19.059 --> 00:31:21.640 complete menace, yet he stayed for 30 years. 00:31:21.720 --> 00:31:25.680 Ah, Salai. His real name was Gian Giacomo Caproti 00:31:25.680 --> 00:31:28.720 d 'Oreno. He was Leonardo's apprentice for three 00:31:28.720 --> 00:31:31.359 decades, and the records are hilarious. Leonardo 00:31:31.359 --> 00:31:33.799 kept a detailed list of Salai's misdemeanors, 00:31:33.819 --> 00:31:37.180 labeling him a thief, a liar, stubborn, and a 00:31:37.180 --> 00:31:39.799 glutton. What did he do? He stole money, pigments, 00:31:39.839 --> 00:31:42.339 expensive silks. Yet Leonardo remained profoundly 00:31:42.339 --> 00:31:44.420 attached to him. Talk about a high -maintenance 00:31:44.420 --> 00:31:47.559 apprentice. That deep, complex attachment to 00:31:47.559 --> 00:31:50.440 both the faithful Melzi and the rogue Salai is 00:31:50.440 --> 00:31:52.339 telling. It also brings us to the historical 00:31:52.339 --> 00:31:54.960 discussion surrounding his sexuality. It has 00:31:54.960 --> 00:31:57.180 been a subject of historical speculation since 00:31:57.180 --> 00:32:00.559 the 16th century, though it's definitively unknowable. 00:32:01.059 --> 00:32:03.440 We know of the sodomy charges brought against 00:32:03.440 --> 00:32:06.680 him in 1476 in Florence, which were ultimately 00:32:06.680 --> 00:32:09.000 dismissed for lack of sufficient evidence. And 00:32:09.000 --> 00:32:11.039 his relationships with his pupils were described 00:32:11.039 --> 00:32:14.279 as very close. Melzi himself described his relationship 00:32:14.279 --> 00:32:16.440 with Leonardo in a letter to Leonardo's brothers 00:32:16.440 --> 00:32:19.819 as loving and passionate. Furthermore, art historians 00:32:19.819 --> 00:32:22.460 have often noted the pervasive themes of androgyny 00:32:22.460 --> 00:32:24.920 and delicate beauty. in some of his later works, 00:32:25.039 --> 00:32:27.799 like St. John the Baptist. Turning to his final 00:32:27.799 --> 00:32:30.460 end, we mentioned the paralysis earlier. He died 00:32:30.460 --> 00:32:33.700 in France in 1519. Leonardo died at Clos Luce 00:32:33.700 --> 00:32:38.440 on May 2, 1519, at age 67, likely from a stroke. 00:32:38.759 --> 00:32:41.339 While the famous image of King Francis I holding 00:32:41.339 --> 00:32:43.720 him in his arms as he died has been immortalized 00:32:43.720 --> 00:32:46.119 by artists, it's generally considered a romantic 00:32:46.119 --> 00:32:49.420 legend invented by Vasari. Why is that? Francis 00:32:49.420 --> 00:32:51.160 I's movements were documented elsewhere that 00:32:51.160 --> 00:32:53.119 day. It's a nice story, but probably not true. 00:32:53.480 --> 00:32:55.380 But the clinical fact of the right -hand paralysis 00:32:55.380 --> 00:32:58.180 remains crucial to understanding his final artistic 00:32:58.180 --> 00:33:01.140 output. It's absolutely essential. That record 00:33:01.140 --> 00:33:04.339 from October 1517 confirming the paralysis explains 00:33:04.339 --> 00:33:06.500 the cessation of his major painting projects. 00:33:06.740 --> 00:33:09.359 It explains why masterpieces like the Mona Lisa 00:33:09.359 --> 00:33:12.200 may have been left technically unfinished. He 00:33:12.200 --> 00:33:14.559 remained left -handed for writing, which explains 00:33:14.559 --> 00:33:17.700 his famous mirror image cursive. But the specific 00:33:17.700 --> 00:33:20.460 fine motor skills needed for that enviable blending 00:33:20.460 --> 00:33:23.680 were gone. And his death didn't bring quiet repose. 00:33:23.759 --> 00:33:26.059 Thanks to the subsequent turmoil of the French 00:33:26.059 --> 00:33:28.660 Revolution, his remains became part of an enduring 00:33:28.660 --> 00:33:31.880 mystery. He was buried in 1519 in the collegiate 00:33:31.880 --> 00:33:34.200 church of St. Florentine at the Chateau d 'Amboise. 00:33:34.660 --> 00:33:36.720 But tragically, the church was almost completely 00:33:36.720 --> 00:33:38.940 demolished during the French Revolution, and 00:33:38.940 --> 00:33:41.119 the site was looted, scattering the contents 00:33:41.119 --> 00:33:43.500 of the graves. However, there was a concerted 00:33:43.500 --> 00:33:46.299 effort in the mid -19th century to find and identify 00:33:46.299 --> 00:33:49.640 his remains. Yes, in 1863, an excavation was 00:33:49.640 --> 00:33:52.740 led by Arsène Hussey. They found a partially 00:33:52.740 --> 00:33:55.420 complete skeleton presumed to be his. Presumed 00:33:55.420 --> 00:33:58.940 based on what? A few small clues. A bronze ring, 00:33:59.099 --> 00:34:01.480 fragments of white hair, and stone fragments 00:34:01.480 --> 00:34:03.819 bearing inscriptions that formed Leonardo's Vinci. 00:34:04.400 --> 00:34:07.039 While the identification is still debated, the 00:34:07.039 --> 00:34:09.559 height, 5 .7 feet, was questioned, but later 00:34:09.559 --> 00:34:12.239 deemed appropriate. There is one compelling detail 00:34:12.239 --> 00:34:14.559 related to his physical limitation. What's that? 00:34:15.050 --> 00:34:17.269 The skeleton's right arm was found folded over 00:34:17.269 --> 00:34:19.789 the head, a posture that some experts speculate 00:34:19.789 --> 00:34:21.849 might correspond to his documented right -hand 00:34:21.849 --> 00:34:24.869 paralysis, suggesting a physical habit or deformity 00:34:24.869 --> 00:34:27.289 caused by the stroke. And the effort to conclusively 00:34:27.289 --> 00:34:30.230 identify those bones continues into the modern 00:34:30.230 --> 00:34:33.610 era using genetics. Exactly. Modern science is 00:34:33.610 --> 00:34:35.530 attempting to achieve authentication through 00:34:35.530 --> 00:34:38.840 DNA testing. They're comparing samples from his 00:34:38.840 --> 00:34:40.840 work, from descendants of his half -brother, 00:34:40.920 --> 00:34:43.579 and from the remains themselves. And crucially, 00:34:43.659 --> 00:34:46.679 in 2021, researchers successfully located and 00:34:46.679 --> 00:34:50.460 documented 14 living male relatives, which provides 00:34:50.460 --> 00:34:53.139 a key genetic link to aid in the authentication 00:34:53.139 --> 00:34:56.079 of those disputed bones. It's amazing. Even 500 00:34:56.079 --> 00:34:58.480 years later, the world's fascination has never 00:34:58.480 --> 00:35:01.139 diminished. He remains, without question, the 00:35:01.139 --> 00:35:04.659 universal genius. Unquestionably. I mean, crowds 00:35:04.659 --> 00:35:07.119 still queue in the Louvre and droves to see the 00:35:07.119 --> 00:35:10.059 Mona Lisa. The museum famously refused to move 00:35:10.059 --> 00:35:12.820 it for their massive 2019 retrospective because 00:35:12.820 --> 00:35:15.460 of visitor demand and the value of his work. 00:35:15.940 --> 00:35:20.059 Just look at the staggering $450 .3 million for 00:35:20.059 --> 00:35:23.500 the Salvatore Mundi in 2017. It shows his enduring 00:35:23.500 --> 00:35:26.880 cultural power. We are still studying, translating, 00:35:27.000 --> 00:35:29.210 and analyzing his writings today. That brings 00:35:29.210 --> 00:35:31.510 us to the close of this incredible deep dive 00:35:31.510 --> 00:35:33.829 into the mind of Leonardo da Vinci. We've explored 00:35:33.829 --> 00:35:36.349 his early genius in Verrocchio's workshop, his 00:35:36.349 --> 00:35:38.570 mastery of the psychological realism in The Last 00:35:38.570 --> 00:35:41.949 Supper and Mona Lisa, and his absolutely revolutionary 00:35:41.949 --> 00:35:44.929 scientific work in anatomy, engineering, and 00:35:44.929 --> 00:35:47.510 physics. And the key takeaway, the paradox we 00:35:47.510 --> 00:35:49.829 set out to explore, is that profound contrast 00:35:49.829 --> 00:35:52.309 between the world -famous painter and the scientific 00:35:52.309 --> 00:35:55.289 pioneer who is virtually unknown to his contemporaries 00:35:55.289 --> 00:35:57.690 in his non -artistic pursuits. He was the first 00:35:57.690 --> 00:36:00.190 to define specific diseases like atherosclerosis 00:36:00.190 --> 00:36:02.389 and liver cirrhosis. The first to use physical 00:36:02.389 --> 00:36:04.469 models like wax ventricles and glaciortas to 00:36:04.469 --> 00:36:06.769 understand human function. The first to articulate 00:36:06.769 --> 00:36:09.070 the physical laws of sliding friction. And yet, 00:36:09.170 --> 00:36:11.929 all of that knowledge was locked away in mirrored 00:36:11.929 --> 00:36:15.670 cursive in those 13 ,000 pages of notes. Many 00:36:15.670 --> 00:36:17.869 intended for a great encyclopedia, but they were 00:36:17.869 --> 00:36:20.730 never organized or published. The potential acceleration 00:36:20.730 --> 00:36:23.030 of the history of science and engineering was 00:36:23.030 --> 00:36:25.889 completely lost to the world for two full centuries. 00:36:26.250 --> 00:36:28.449 His knowledge was arguably the greatest single 00:36:28.449 --> 00:36:30.590 collection of discovery in Europe at the time, 00:36:30.630 --> 00:36:33.150 but its immediate impact on civilization was 00:36:33.150 --> 00:36:35.989 negligible. It was negligible because he, or 00:36:35.989 --> 00:36:37.849 those who inherited his work, kept it locked 00:36:37.849 --> 00:36:40.750 away, hidden from the world of academia. So here 00:36:40.750 --> 00:36:42.789 is our final provocative thought for you to take 00:36:42.789 --> 00:36:46.400 away. If 13 ,000 pages of epic -making discovery, 00:36:46.619 --> 00:36:49.079 from the laws of friction to the true nature 00:36:49.079 --> 00:36:51.619 of the circulatory system, can disappear for 00:36:51.619 --> 00:36:54.760 200 years, what major scientific or engineering 00:36:54.760 --> 00:36:57.500 revolutions are locked away today, waiting for 00:36:57.500 --> 00:36:59.559 the right person to simply open the drawer and 00:36:59.559 --> 00:37:02.760 publish? Does genius truly depend only on creation? 00:37:03.280 --> 00:37:05.960 Or does the real value of revolutionary knowledge 00:37:05.960 --> 00:37:08.219 ultimately rest entirely upon its communication 00:37:08.219 --> 00:37:11.500 and its dissemination? It forces us to confront 00:37:11.500 --> 00:37:13.840 the fact that having the greatest possible knowledge, 00:37:13.880 --> 00:37:17.019 if it's isolated, is useless to humanity. And 00:37:17.019 --> 00:37:19.880 the paradox of Leonardo is that the genius who 00:37:19.880 --> 00:37:23.000 saw farther than anyone was perhaps the worst 00:37:23.000 --> 00:37:25.559 communicator of his own vision. An incredible 00:37:25.559 --> 00:37:28.380 mind and an incredibly dense deep dive. Thank 00:37:28.380 --> 00:37:30.019 you for joining us. We'll see you next time.