In Leonardo da Vinci, Walter Isaacson narrates the life, accomplishments, and struggles of the Italian painter, engineer, and scientist—the ultimate Renaissance man. He traces Leonardo’s evolution, finds explanations for his flaws, and extracts lessons from his life and work that you can apply to your own. (Shortform note: We refer to Leonardo by his first name rather than “da Vinci'' throughout the guide because, having been born out of wedlock, he didn’t have a family name. “da Vinci” indicates that he came from the town of Vinci.)
Isaacson believes that making cross-disciplinary connections is at the core of being innovative, creative, and, ultimately, a genius, and there’s no better example of this than in Leonardo da Vinci. His studies in science, engineering, and art helped him satisfy his curiosity and understand the world around him, and they contributed to making his masterpieces scientifically accurate, ahead of his time, and mysterious. (Shortform note: David Epstein would agree with Isaacson's idea of genius. In Range, Epstein argues that the way to achieve excellence is by having a generalist approach where you explore and experiment with different skills and areas of knowledge.)
Isaacson has written multiple books on some of the greatest geniuses of our time and past generations, such as Steve Jobs (2011) and Benjamin Franklin: An American Life (2003). Leonardo da Vinci (2017) is one of his latest additions to the catalogue of thinkers and makers who shaped the world we live in today. (Shortform note: Adding to that roll call, Isaacson is currently working on a biography of Elon Musk.)
The most important sources for this biography were the 7,200 pages of Leonardo’s notebooks. Isaacson also traveled to see his works of art in person and read academic articles and other biographies about Leonardo, including three by Leonardo’s contemporaries. (Shortform note: Leonardo’s notebooks were useful not only for Isaacson to create this biography, but also to appreciate the importance of saving ideas for posterity. Comparing his experience writing Leonardo’s and Jobs’ biographies, Isaacson remarked that it was hard to reconstruct Jobs’ early process because many of his digital notes had been destroyed when the operating system of the computer they were in became obsolete.)
This guide explores Leonardo’s biography in layers: Part 1 covers the known facts of his life, Part 2 explores the three key elements of his genius (universality, creativity, and human flaws), and finally, Part 3 discusses the lessons we can learn from him. We also discuss the historical context of Leonardo's life and work and relate Isaacson's lessons to other authors who offer complementary advice.
Leonardo spent his life in many places—Vinci, Florence, Milan, Rome, and France. This section will explore his life from his birth in Vinci in 1452 to his death in France in 1519.
Leonardo was born in Vinci, Italy, on April 15, 1452. He lived there for the first 12 years of his life, alternating between his mother’s home and his paternal grandparent’s home. (Shortform note: Historians say that Leonardo was more specifically born in Anchiano, a village near the town of Vinci.)
According to Isaacson, throughout his life, Leonardo was popular and widely liked. He was handsome, stylish, and made friends easily. He expressed himself through his clothes and had a preference for short, pink robes. He was generous and uninterested in money. Leonardo worked just enough to support himself and spent the rest of his time investigating subjects that interested him.
(Shortform note: According to the 5-factor model of personality, Leonardo was very open (which allowed him to learn and create without limitations), moderately conscientious (which made him distracted and prone to procrastination), very extroverted (which made him friendly and outgoing), highly agreeable (which made him charming), and moderately neurotic (which led him to often feel unsatisfied with his work).)
Despite being popular, Leonardo was different from his contemporaries, which gave him the freedom to become the genius he was. Isaacson identifies four key differences between Leonardo and his peers:
1. He was an illegitimate son. Leonardo was born out of wedlock, which Isaacson claims had some advantages: His uncertain social and financial status freed him to follow his career and education with independence and boldness.(Shortform note: The Renaissance was a golden age of illegitimacy in Italy because men wanted to ensure they would have an heir.)
2. He was left-handed. Isaacson says Leonardo learned to write from right to left so that he wouldn’t smudge the ink with his hand. Using his left hand also made his brush strokes unique. (Shortform: Scientists have analyzed some pages of Leonardo’s notebooks and concluded that he was likely ambidextrous but used his left hand more often than his right.)
3. He was gay. And he didn’t hide it, despite sodomy being illegal. In his art, male nudes were lovingly depicted with much detail, while his portraits of women had psychological insight rather than anatomical detail. (Shortform note: Many pop culture representations of Leonardo don’t address his sexuality. Perhaps this will change in the movie adaptation of Isaacson’s biography.)
4. He was vegetarian. According to Isaacson, Leonardo loved animals and hated how they were treated. He dressed in plant-based fabrics, avoided killing insects, and bought caged birds to set them free. However, his love of animals didn’t get in the way of his scientific pursuits. He once opened up a pig whose heart was still beating to see how the ventricles worked. (Shortform note: Leonardo’s vegetarianism might have been part of a broader pacifist philosophy. Some argue that his designs for weapons never came to life because he couldn’t bring himself to create tools for destruction. However, the fortresses he designed for his patrons did end up being used. Perhaps he felt that fortresses were a force for peace rather than war.)
In 1464, Leonardo began living with his father in Florence, the perfect setting for young Leonardo’s development. Isaacson explains that the trading city was a melting pot of new ideas. Its intellectuals believed in the ideals of Renaissance humanism, especially in finding happiness through knowledge. The growing upper class was keen to display their wealth through their arts patronage, giving artists opportunities to create and collaborate.
(Shortform note: Florence is called “the cradle of the Renaissance” because the cultural revolution was “born” there. Florentine authors, such as Dante Alighieri, paved the way by exploring and writing about these ideas in Italian, rather than Latin, bringing them closer to the general population.)
In 1468, Leonardo’s father got him an apprenticeship with Andrea del Verrocchio, an artist and engineer. Isaacson says the apprenticeship offered Leonardo opportunities to learn fundamental painting techniques he would later use more effectively than his contemporaries, two of which include: 1) Drapery studies and chiaroscuro, which used shading to make images appear three-dimensional. 2) Sfumato, which lightly diffused borders instead of sharply delineating edges.
According to Isaacson, Verrocchio’s work was an important influence on Leonardo. For example, Verrocchio’s statue of David (which Leonardo likely modeled for) has many hallmarks that Leonardo would learn and surpass: the dynamic body, the beautiful curls, the anatomical preciseness, and the mysterious facial expression.
(Shortform note: Verrochio’s influence on Leonardo cannot be overstated. Verrochio was a sculptor as well as a painter, which gave him a knack for creating three-dimensional figures in painting, a skill Leonardo began developing while working for him.)
The Medici were de facto leaders of Florence who helped shape the Renaissance era through their patronage of the arts. Isaacson explains, however, that some artists were more successful than others in securing that patronage. For example, Botticelli earned their support by inserting members of the Medici family into historical and biblical paintings. Leonardo, on the other hand, didn’t compromise his work to court favor. (Shortform note: Some refer to the Medici as the “godfathers” of the Renaissance, and with good reason. They fostered the arts using their own money and, thanks to their diplomatic savviness, led a period of relative peace.)
Isaacson says this was a habit Leonardo continued throughout his life: He sought and took money from patrons, but only for work that he was excited about. He wasn’t afraid to leave employers waiting while he found the right way to approach a piece of work, or to ignore them altogether if the work they wanted him to do was uninspiring. (Shortform note: The patronage system defined the careers of Renaissance artists. Patrons helped the arts flourish and enabled artists to become more than anonymous craftsmen. However, patrons could be fickle and they were often more motivated by social competition than the pursuit of knowledge or beauty.)
Lorenzo de’ Medici sent Leonardo to Milan as a diplomatic envoy, opening a new chapter in Leonardo’s life. Lorenzo often leveraged Florence’s cultural capital in his diplomatic relations with the other Italian city-states. On this occasion, Isaacson argues that Lorenzo leveraged Leonardo’s skills as a gift to the Duke of Milan, Ludovico Sforza.
Isaacson explains that Milan offered Leonardo many advantages. First, it was larger than Florence but it didn’t have as many accomplished artists, so he would have less competition. Second, Milan’s duke was filling his court with artists, engineers, and philosophers, so Leonardo had a source of employment and the opportunity to collaborate with other intellectuals.
(Shortform note: Much like Florence, Milan’s economic growth allowed it to become an important center of Renaissance culture. Its economy was strong thanks to its agriculture, manufacturing capacities, and geographical importance in trade routes. The Sforza dynasty was short-lived, but it represented the height of the Renaissance in the region.)
Once in Milan, Leonardo applied for a job at the Duke’s court. Isaacson claims that Leonardo emphatically promoted his ability to design weapons and war mechanisms. He did this because, first, he knew the Duke would be interested in strengthening his military power, and second, he was going through a painting rough patch and was feeling frustrated with his lack of accomplishments. However, the only military project Leonardo ever carried out for the Duke was a survey of the castle’s defenses.
Leonardo eventually secured his entry into Ludovico’s court as a producer of plays, pageants, and social events. According to Isaacson, these events legitimized Ludovico’s power, kept his people distracted, and kept family members with claims to power busy. On his part, Leonardo finally achieved the recognition he craved and could support himself by exercising his creativity and multidisciplinary approach through the combination of art and engineering.
Unfortunately, Ludovico was an unreliable employer and Leonardo began searching for other opportunities in the late 1490s, even going so far as to write letters in the third person praising his own work to possible patrons. In 1499, the French army invaded Milan and Ludovico fled. Leonardo remained in Milan for a few months, but in 1500, he decided to return to Florence. (Shortform note: Despite his unreliability, Ludovico was Leonardo’s most important patron. He commissioned some of his most significant work, connected him to a vibrant court that allowed Leonardo to pursue all his interests, and ensured Leonardo’s status by granting him the only piece of land he would ever own.)
In 1490, while living in Milan, 10-year-old Gian Giacomo Caprotti da Oreno, nicknamed Salai (meaning little devil), moved in with Leonardo. According to Isaacson, he was Leonardo’s apprentice, the companion and possible sexual partner who stayed with him the longest, and the inspiration for many of Leonardo’s drawings. Gian earned his nickname through acts of mischief—Leonardo’s notebooks include five references to Salai stealing from him and to fights they had where Leonardo let the boy have his way. (Shortform note: There’s some speculation that Salai was Leonardo’s model for several paintings, including Matthew and Phillip in “The Last Supper,” Saint John in “Saint John the Baptist,” and even Lisa in the “Mona Lisa.”)
Leonardo returned to a different Florence from the one he had known. The city had gone through a conservative period and lost the vibrancy of its culture and economy. However, the Florentines were closing that chapter and returning to their roots. Isaacson argues that, at first, Leonardo fit well into this cultural context. He symbolized what Florence was striving to return to, and he played the part of a stylish eccentric.
(Shortform note: The cultural changes in Florence were the result of Girolamo Savonarola, a friar who preached against corruption in the government and church. When the King of France invaded Florence in 1494, Savonarola negotiated on behalf of Florence and became the leader of the city-state. He purged the Florentine government, openly criticized the Pope and the Church, and organized the “burning of the vanities,” where people burned their books, jewelry, and any other object that enticed them to sin. Eventually, political enemies (including the Pope) succeeded in removing Savonarola from leadership and he was killed in 1498.)
In Florence, Leonardo opened a workshop where he fostered a collaborative approach. Leonardo would paint an original version of a work and teach his assistants to produce copies. Isaacson explains that, often, those copies were being produced at the same time as the original, so Leonardo used them to test out different ideas, resulting in different versions of the same paintings. Also, he didn’t sign his paintings, since they were a product of the workshop rather than a product of Leonardo. This collaborative process led to some paintings being difficult to label as authentic Leonardos.
(Shortform note: This setup corresponded with the organization of most artists’ workshops in Renaissance Italy. It allowed the workshop’s master to produce works of art for all kinds of patrons, whether they were as rich as a duke or not. It also allowed for experimentation without losing the workshop’s signature style that differentiated it from the competition.)
In 1502, around the age of 50, Leonardo worked for his most ruthless boss yet: Cesare Borgia. Cesare was on a military campaign to subdue several city-states and bring them under the power of the Pope (his father). During that campaign, Isaacson believes that Florence offered Leonardo’s services as part of a diplomatic package to ensure that Cesare wouldn’t invade the city. This placement gave Leonardo the opportunity to live out his military engineering dreams. Isaacson reports that, during this time, Leonardo:
(Shortform note: Cesare Borgia was synonymous with treachery and violence throughout Italy. Knowing that he had more enemies than allies, and that even his alliances were shaky, he hired Leonardo to help protect his territories. In The Prince, Niccolò Machiavelli cites Cesare Borgia as an example of how fortune can make or break a leader. As the son of a pope, he had enormous success establishing his own state in central Italy. But soon after his father died, his state crumbled. He failed to either foresee the danger or adapt to the times, and all his cunning and brutality couldn’t protect him from being overthrown. Machiavelli argues that if Cesare had better prepared for the inevitability of his father’s death, he might have held onto power longer.)
In 1506, Leonardo returned to Milan to resolve a dispute over a painting, but he stayed there after resolving it. Isaacson argues that he stayed because he had no interest in returning to Florence and the visibility he had there as an artist. To appease the Florentine government, Leonardo asked the French rulers of Milan to intervene on his behalf so he could stay in Milan. Compared to Florence, Milan was a vibrant city that offered Leonardo more opportunities, and Isaacson claims he stood out less than in small-town Florence. In Milan, he also had the favor of the King of France and the French governor of Milan.
(Shortform note: Leonardo’s preference for Milan is repaid by how the city treasures his legacy. In 1872, the city built a statue of Leonardo with a flowing beard and contemplative brow. Some blocks away, a sculptural rendition of Leonardo’s maps of Milan sits in the middle of the old city.)
The French governor of Milan, Charles d’Amboise, became Leonardo’s patron. Isaacson claims that Leonardo became the most important member of Charles’s court in Milan. Charles wanted to surround himself with artists, engineers, and scientists—and Leonardo was all those things in one man. Charles gave Leonardo a salary and a home to live in, along with Salai. He was also protective of Leonardo. For example, when the Florentine government demanded that Leonardo return to finish some commissions he abandoned, Charles chastised them for badgering Leonardo and told them to take better care of their city’s most accomplished son. Until his death in 1511, Charles was a kind patron to Leonardo.
(Shortform note: Although Charles admired Leonardo, when he had his portrait made, he commissioned it to Bernardino de’ Conti. Perhaps he wanted a more traditional portrait than what Leonardo would have done.)
In 1507, Leonardo adopted 14-year-old Francesco Melzi. Isaacson explains that, although Francesco had living parents who could support him, his family saw the adoption as a way to ensure a successful career as an artist. After Charles d’Amboise’s death in 1511, Leonardo moved into the Melzi family villa until he could find new employment. (Shortform note: We have Francesco to thank for safeguarding Leonardo’s notes. When Leonardo died, he left his notebooks to Francesco, who took precious care of them all his life. Francesco also inherited some of his artistic skills from Leonardo, including his attention to detail and mastery of sfumato.)
In 1513, after a few years with the Melzi family, Leonardo found new patrons who took him to Rome. Giovanni de’ Medici (of the Florence Medici) had become Pope Leo X and his court was looking for artists and architects. (Shortform note: Pope Leo X has many claims to fame, besides employing Leonardo. The Renaissance flourished in Rome under his watch, with Raphael, Michelangelo, and many other artists working for him. But the pope enjoyed many earthly pleasures other than art, and his ostentation of wealth, corruption, and promiscuity helped diminish the Catholic Church’s leadership, opening it up to a period of Reformation by leaders such as Martin Luther.)
During his time in Rome, Leonardo didn’t accept any new painting commissions. Instead, Isaacson says he focused on improving the paintings he had brought with him from Milan. He also took engineering jobs for the court, such as draining marshes and designing a coin mint. Isaacson claims that Leonardo’s time in Rome was brief and unenjoyable. He got into arguments with people who worked for him and with those whom he believed were copying his ideas. The Pope also ordered him to stop performing dissections, limiting his anatomy studies. Since he wasn’t producing any paintings, he lost the Medici’s favor, and he decided to find other employment.
(Shortform note: Another source of discomfort for Leonardo was that he didn’t have friends in Rome. The other artists there, especially Michelangelo, saw him as competition, and his only friend in the city was the architect Donato Bramante, who died in 1514.)
In 1516, Leonardo and Francesco moved to France. Joining them was Battista de Vilanis, a new servant Leonardo had become attached to, according to Isaacson. Along the way, the group separated from Salai (Leonardo’s apprentice and muse). Salai moved to Leonardo’s estate in Milan (a vineyard that Ludovico Sforza had given him as payment for some work), where Salai later built a house. He would visit Leonardo a few times in France, but they never again lived together. (Shortform note: Ludovico gave Leonardo the vineyard as payment for “The Last Supper” and it was Leonardo’s confirmation of having become a land-owning citizen of Milano.)
Leonardo’s move from Rome to France was thanks to King Francis I, who in 1515 invited Leonardo to his court. Francis admired the Italian Renaissance, and Leonardo in particular, and he wanted to bring that cultural revolution to France. Isaacson believes that Francis was the perfect patron for Leonardo’s last years. They shared a wide-ranging curiosity and taught each other what they knew. Francis didn’t condition his stipend on paintings or other works, and he let Leonardo work on projects that interested him, such as court events and works of engineering.
(Shortform note: Experts agree that the relationship between King Francis I and Leonardo was mutually beneficial. Leonardo was a “father figure” to the king, and Francis offered the comforts the aging artist needed: a beautiful home, a secure place in court, a salary, and admiration.)
At some point before October of 1517, Leonardo suffered a stroke that left his right hand incapacitated. Before his death, Leonardo wrote his will. Isaacson reports that he divided his property among Francesco, his half-brothers, Battista, Salai, and his cook. (Shortform note: Isaacson states that Leonardo wrote his will in 1518, but most other sources claim he wrote it in 1519, days before his death.) Leonardo died in 1519, days after turning 67. (Shortform note: The cause of death is unknown, but it’s possible he had another stroke.)
In Part 2, we’ll explore the three qualities or elements that made Leonardo a genius. Isaacson argues that Leonardo deserves this moniker. While he didn’t have a superhuman mind or access to formal education, he nurtured the qualities he did have, and they led him to develop his unique genius. Those qualities were:
1) A universal curiosity that he channeled into observation and experimentation. He didn’t restrict himself to any specific subject, and Isaacson believes that this allowed him to make insights that were out of reach for people who only focused on only one skill or area. (Shortform note: Experts agree that curiosity is an essential ingredient of genius. Curiosity prompts you to seek knowledge by asking questions, experimenting, and making connections others can’t see.)
2) The creativity that resulted from his intellectual curiosity and the free range of his imagination. Isaacson believes that Leonardo’s creativity allowed him to create art that melded scientific accuracy with the expressions of a powerful inner life. (Shortform: Elizabeth Gilbert, author of Big Magic, would agree with this explanation for Leonardo’s creativity. She writes that creativity is the exploration of gifts within you—like Leonardo’s inquisitiveness and imagination.)
3) Human flaws—as Isaacson explains, Leonardo battled with two major flaws that also shaped his unique genius: 1) perfectionism, which led him to abandon projects he couldn’t produce in the same way he had envisioned them, and 2) a lack of discipline, which meant he wasn’t bothered by time, money, or even the limits of what was possible in his time.
Isaacson explains that Leonardo’s perfectionism and lack of discipline meant he left behind unfinished works of art, engineering projects he designed but never built, and treatises on art and science he never finished or published. This perfectionism set humanity back some centuries because other people had to rediscover many of the insights he had already made. (Shortform note: By some estimates, if Leonardo had published his treatises, science would have advanced by one era.)
But these flaws also humanized him and gave a distinct edge to his genius. Isaacson argues that his unfinished projects were often innovations that were centuries ahead of his time, or works in constant progress that he felt no rush to complete. (Shortform note: Leonardo’s flaws humanized him to the point that some have called him “the patron saint of perfectionists, procrastinators, unsuccessful job applicants, and exasperated second-language students.”)
In the next three sections, we’ll explore these elements of his genius (universal curiosity, creativity, and human flaws) and the most important outputs of each.
As Isaacson makes clear, the starting point for Leonardo’s genius was his universal curiosity. He studied a range of subjects and applied everything he studied to his works of art, while also bringing his artistic insights into his scientific explorations. The key output of his universal curiosity was the self-directed education that turned him into the ultimate Renaissance man. This section will discuss how he shaped his education.
(Shortform note: Leonardo was only one example of the cultural revolution taking place. Many other artists brought together science, engineering, painting, sculpture, and more thanks to the commercial and intellectual exchange taking place in cities like Florence and Milan.)
Leonardo was different from other Renaissance intellectuals because he didn’t base his learning on examining the classics since he couldn’t speak Latin or Greek (although he tried, unsuccessfully, to learn Latin). Isaacson explains that, instead, Leonardo learned by making observations, carrying out experiments, and refining his insights.
Isaacson explains that Leonardo became a precursor of modern scientists:
(Shortform note: At the basis of Leonardo’s scientific insights was his ability to observe, a learnable skill—except it might be impossible for most people to learn to observe like Leonardo. Scientists are currently working on sequencing Leonardo’s genome to see whether his vision or other senses were genetically different and predisposed to detailed observation.)
The best testament to Leonardo’s self-directed learning is the notebooks he systematically kept, starting in the 1480s. The practice of keeping a notebook was popular during the Renaissance, but Isaacson argues that no one amassed such extensive and diverse material as Leonardo. (Shortform note: This digitized fragment of one of his notebooks shows some of the variety in his notes. The front page (recto) contains detailed notes on hydrology and hydromechanics, while the back (verso) has drawings he made while dissecting an ox.)
Some of the themes that filled his notebooks include:
(Shortform note: Leonardo collected all his valuable ideas and information in one single notebook—like a bullet journal. However, the modern bullet journal method, as Ryder Carrol describes it, can be a lot more organized. For example, you can decide ahead of time what kind of topics you’ll want to write about and customize your journal to have a section for each topic. This will allow you to keep your anatomy and hydrology studies separate, for example, but might prevent cross-pollination of ideas from happening on the same page.)
Leonardo nurtured a passion for mathematics, especially geometry, throughout his life. Isaacson argues that, to Leonardo, painting was both an art and science because artists need a deep understanding of mathematics to convey their imagination through their art. (Shortform note: Researchers argue that Leonardo’s ability to create three-dimensional images is related to his affinity for solid geometry and stereometry (the measurement of solid bodies).)
During his first stay in Florence, Leonardo’s father paid for his education at an abacus school. Isaacson argues that Leonardo’s takeaway from this education was using analogies and patterns. For example, he took what he knew about water eddies and hypothesized that the aortic valve used a similar process. (Shortform note: Some argue that Leonardo’s ease with making analogies was the basis of his genius. He found common patterns between phenomena to understand each individual phenomenon. For example, once he threw a stone inside a well at the same time a church bell rang. He saw the rings rippling out around the stone and imagined that sound must also travel in waves, just like water.)
From 1494 to 1499, while he lived in Milan, Leonardo and mathematician Luca Pacioli were both on Duke Ludovico’s payroll. During this time, Luca taught Leonardo geometry and algebra. Isaacson reports that Leonardo’s notebooks contain passages of Luca’s word-for-word explanations of difficult topics so that he could review them over and over.
Leonardo and Pacioli also collaborated on a book: De Divina Proportione. Luca wrote the book to explore the importance of proportion in architecture, mathematics, anatomy, and art. Leonardo was fascinated by the topic and produced 60 illustrations for the book. Always at the cutting edge, Leonardo innovated by making the illustrations see-through instead of colored so they could be easily understood. He also applied his artistic skills of light and shading to make the objects appear three-dimensional and realistic.
(Shortform note: Pacioli’s mathematical insights influenced Leonardo’s art. Divine proportion is just another term for the golden ratio, an irrational number (roughly 1.618) that appears in architecture, nature, and, of course, works of art. Critics argue that Leonardo followed this mathematical pattern in his art, as you can see here.)
Isaacson claims that Leonardo's work made dimensionality the greatest artistic achievement of the Renaissance, possibly thanks to the following two gains from his study of optics:
1. Optics enhanced his understanding of light, shades, and edges. Isaacson reports that, through experimentation and dissection of eyeballs, Leonardo learned that the eye perceives images through the entire retina. This means that the brain perceives scenes as a whole, not as individual objects separated by sharp edges. (Shortform note: Despite the breakthroughs Leonardo made in understanding how the eye works, he believed that the lens was circular rather than an ellipsoid. This might be because, to prevent the contents of the eye from spilling when he dissected it, he boiled it, which resulted in the lens changing shape.)
2. Optics refined his use of perspective. He went beyond linear perspective (how to make a flat surface seem deep) and studied acuity perspective (how objects become less distinct when they are farther away). Isaacson explains that Leonardo understood that he needed to paint objects in the background more diffusely than those in the foreground. (Shortform note: To ensure he was drawing with accurate perspective, Leonardo built a perspectograph: a sheet of glass positioned in front of a frame with a small slot through which he looked at a scene he wanted to paint. Looking through the slot, he traced the scene on the glass, then used those tracings to guide his initial drawings.)
Architecture and engineering are areas where Leonardo didn’t leave concrete marks. None of his designs came to fruition, and Isaacson argues that this was because they were too ambitious for his time. (Shortform note: Centuries after Leonardo, other inventors had similar ideas and finally got around to making the machines he designed. See whether you can match Leonardo’s drawings with the modern-day machines they resemble.)
In terms of architecture, he developed plans for new cities, royal palaces and villas, and churches. Isaacson says Leonardo was the first architect to systematically analyze the causes of wall fissures, and he developed plans to make cities more hygienic and prevent plague outbreaks. (Shortform note: You can see a scale model of Leonardo’s plans for an ideal city.)
Isaacson reports that Leonardo's interests in engineering spanned aeromechanics, hydraulics, and military engineering. He designed flying machines and complex water management systems, including a plan to change the course of the Arno river. In military engineering, he designed several weapons. (Shortform note: If you travel to Milan, you can see some real-life examples of Leonardo’s inventions, such as a giant crossbow and sliding doors in water canals designed to control the flow of water.)
While Leonardo didn’t manage to construct working prototypes for his designs, Isaacson claims he made significant engineering and scientific advancements:
(Shortform note: For all his learning and scientific breakthroughs, Leonardo is a lonely branch in the tree of scientific progress. Since he learned from his own experience, it’s difficult to trace his ideas back to medieval thinkers. His insights are not part of a lineage of scholarship because he could only make them thanks to his experiments. Also, since his notebooks weren’t published until centuries later, his ideas didn’t help the next generation. By not leaving behind a published record of his learning, he had a limited impact on the breakthroughs that came after him.)
During his first stay in Milan, Leonardo collaborated with anatomy scholars at the University of Pavia who taught him to perform dissections. According to Isaacson, his studies of anatomy allowed him to explore two central questions:
1) How does man fit into the universe?
2) How do emotions transform into gestures and movements?
Isaacson identifies several scientific breakthroughs Leonardo made through dissections and observations of living people and animals:
(Shortform note: Although Leonardo’s contributions to anatomy are better known than those of his contemporaries, the Renaissance was a time of intense collaboration between artists and physicians. Artists needed physicians’ access to human bodies so they could depict them better, and physicians needed artists’ skills to capture what they discovered. This led to fruitful collaborations between both areas of human knowledge, a hallmark of the Renaissance.)
As Isaacson explains, Leonardo’s interest in water was second only to his interest in the human body. He explored how water moved and shaped the earth, and he made it a central part of his art and engineering projects. (Shortform note: His interest in hydrology seems to have started when he saw a flood in his childhood.)
Leonardo made several breakthroughs in this area. He invented goggles, floats, and instruments to measure the current and movement of rivers. Also, Isaacson says Leonardo carried out experiments that prompted important discoveries:
(Shortform note: Some consider Leonardo to be one of the founding fathers of hydrology. He previewed a basic tenet of hydrology when he realized that the amount of water that builds up on mountains each year is the same as the amount that comes down through rivers and rain.)
Leonardo’s curiosity about the earth led him to study its place in the universe. According to Isaacson, Leonardo made many astronomic insights that were ahead of his time:
(Shortform note: Leonardo hypothesized that he could use mirrors to construct a machine to help him see celestial bodies more clearly, and he made some sketches of a proto telescope.)
Isaacson cites Leonardo's approach to the microcosm-macrocosm analogy—a comparison of the human body’s functions with those of the earth—to show how he was willing to abandon a flawed idea. The microcosm-macrocosm analogy claimed that the human body and the earth behaved in similar ways. (Shortform note: The microcosm-macrocosm analogy is present in ancient Greek culture, religious philosophy from the Middle Ages, Buddhism, and Hinduism.)
However, Isaacson argues that Leonardo saw the limitations of that analogy through his studies. First, he realized that the mechanisms that allow blood to irrigate the body are different from the mechanisms that make water emerge from deep in the earth. Second, he learned that veins and arteries age and become thinner, but river beds tend to grow each year. (Shortform note: Some scientists still find the analogy useful, and see evidence of its relevance in similarities between, for example, bacterial division patterns and supernova explosions.)
Because the facts invalidated the analogy, Leonardo let go of it. However, he continued using it in his art. Although the mechanisms were different, the beauty and unity of human and animal bodies reflected the beauty and unity present in the earth and the universe. (Shortform note: Leonardo might have held on to the analogy as spiritual as well as aesthetic guidance. Some scientists argue that his vegetarian diet is a result of his belief in the interconnectedness of organisms and systems of all sizes.)
The second key element of Leonardo’s genius was his creativity, which, according to Isaacson, was the result of his unbridled imagination plus his scientific insights. This section will discuss how he expressed his creativity in three of his masterpieces.
(Shortform note: Isaacson’s description of Leonardo’s creativity dispels some common myths about creativity. For instance, it shows that creativity requires both logical and intuitive thought patterns, and that creativity doesn’t depend on sudden bursts of inspiration because Leonardo continuously nurtured his imagination and scientific insights.)
According to Isaacson, Leonardo’s “Vitruvian Man” was the result of his explorations of mathematics and philosophy and his collaboration with architects Francesco de Giorgio and Giacomo Andrea. (Shortform note: The drawing is at the Gallerie dell’Accademia in Venezia and you can see a digitized version here.)
In 1490, Leonardo and Francesco traveled together to Pavia to consult on the design of a church. During the trip, they studied a copy of a classical treatise on architecture written by Marcus Vitruvius Pollio in the first century BCE. On their return, both of them plus Giacomo became engrossed in drawing a Vitruvian man, sharing their sketches and conversations on its deeper meaning. (Shortform note: An architect discovered Giacomo’s drawing in 1986 after being lost to time after his death during the French invasion of Milan.)
Isaacson explains that the Vitruvian Man was a metaphor for the relationship between man and the cosmos. Vitruvius argued that the design for a temple should follow the proportions of a “well-shaped” man. He gave specific measurements for that well-shaped man and explained how to draw him inside a circle and a square to use as a foundation for the temple’s design. (Shortform note: The Vitruvian Man is related to the macrocosm-microcosm analogy, with the circle representing the sky and the square representing the earth.)
Vitruvius’s metaphor became popular during the Renaissance because it resonated with humanist ideals. Isaacson explains that the metaphor celebrated the place of individuals in the universe as worthy of straddling the immediacy of the earth and the timelessness of the cosmos. (Shortform note: The precise measurements also indicated that it was possible to know how humans fit in the world and the broader universe.)
Of all the drawings he and his friends made, Isaacson argues that Leonardo’s “Vitruvian Man” became the definitive one thanks to his scientific and artistic commitment. 1) While the other two produced sketches, he planned the drawing over several sketches and produced a confident final illustration. 2) He drew the details of the man’s body, face, and hair with delicate traces, making his subject a metaphor for the human and the divine. 3) He followed Vitruvius’s instructions for the placement of the man inside the circle and the square precisely, but he made adjustments to the measurements of the man. Isaacson explains that those adjustments came from his studies of anatomy and his willingness to challenge received knowledge.
(Shortform note: Another change that elevated Leonardo’s drawing was placing the legs and arms in two different positions, thus creating an equilateral triangle with the legs.)
Between 1495 and 1498, Leonardo painted “The Last Supper” for Duke Ludovico—a commission that tested the duke’s patience but showcased Leonardo’s masterful application of narrative, symbology, and optics. Isaacson reports that the duke was setting up his family’s mausoleum in the Santa Maria delle Grazie monastery and he asked Leonardo to paint one of the walls of the monastery’s dining room. (Shortform note: You can see “The Last Supper” here in high definition.)
Leonardo’s creation process was haphazard, which made the monastery’s prior (or leader) and the duke uneasy. Isaacson explains that, some days, Leonardo would spend hours painting, not stopping to eat, and people would even gather around him to watch him work. On other days, he would spend hours simply looking at his work in progress, or arrive, paint a single stroke, and leave. The prior complained about his erratic progress to the duke, and Leonardo explained that working slowly allowed him to perfect his ideas. He also warned that he would use the monastery’s prior as a model for Judas Iscariot if the man didn’t stop badgering him.
(Shortform note: Besides being placed at the Sforza family’s mausoleum, the painting included other “Easter eggs” that referenced Ludovico and his court. For example, Leonardo had members of the Milanese court model the different characters in the painting, and the tapestries in the painting were reminiscent of the tapestries in Ludovico’s castle.)
The duke’s patience ran thin when his wife died. She was placed in the mausoleum, so he went to the monastery and ate dinner there every week. Isaacson says that to speed Leonardo up, Ludovico had him sign a contract clearly stipulating the deadline. But the duke’s patience was finally rewarded with a work of art that encapsulates much of Leonardo’s genius through three key characteristics that Isaacson identifies. (Shortform note: Besides rewarding the duke’s patience, the painting also catapulted Leonardo to the widespread recognition he craved.)
Isaacson explains that the painting shows the aftermath of Jesus declaring that one of his apostles would betray him that night. Leonardo lifted each apostle’s emotions and reactions from the Bible and painted gestures and expressions that would showcase them. (Shortform note: There’s been a lot of speculation about the gestures the apostles make in the painting and whether they convey a secret message from Leonardo. However, it’s most likely that they just convey the drama of the situation through gestures that would have been commonly understood at that time.)
Jesus’s gestures are symbolic of the Eucharist (a Christian rite of thanksgiving and commemoration of the Last Supper). Isaacson explains that Christ’s hands are signaling toward a glass of wine (symbolizing his blood) and a piece of bread (his body). After declaring that one of his followers would betray him, the Bible describes how he blessed the wine and bread and shared it with the apostles because his blood would cleanse their sins. Leonardo chose the placement of Jesus’s hands carefully: The first thing you see is the hand pointing toward the piece of bread and inviting you to participate in the Eucharist.
(Shortform: Although he was mindful of tradition, Leonardo might not have bought into the religious meaning of the painting. Critics speculate that Jesus doesn’t have a halo because Leonardo thought Jesus was a regular person.)
Isaacson argues that Leonardo applied his knowledge of optics to “The Last Supper” in two ways:
1) He made Jesus larger than the other characters. He painted him in front of an open window, knowing that a light background makes objects appear larger. This way, he achieved the dominant effect he desired without making Jesus seem unnatural compared to the other characters.
2) He deftly applied the laws of natural and artificial perspective—and disregarded them when necessary. All the straight lines in the painting meet at a vanishing point on Jesus’s forehead. This helped Leonardo create a natural perspective and make the painted room seem real—like an extension of the actual dining room, with even the tapestries in the painting aligning with the tapestries in the monastery room. To achieve this effect, he stuck a nail in the center of the wall and carved radiating lines on the wall to guide his paintbrush.
However, natural perspective has its limitations, which Isaacson says Leonardo got around by playing with artificial perspective. The wall is too large and the room too narrow for a viewer to stand at the perfect distance from the painting to take the scene in without it looking distorted. Artificial perspective made it possible to adjust how viewers would see the painting, depending on where they were in the room. Isaacson identifies a series of optical illusions Leonardo applied to make the viewing experience smooth, such as:
(Shortform note: Leonardo’s mathematical accuracy in the creation of this painting’s perspective also serves a symbolic function. Since all the lines converge on Christ’s forehead, he is the vanishing point where all the traces begin and end.)
Isaacson reports that Leonardo began working on this masterpiece in 1503 and continued perfecting it until his death, putting into practice his knowledge of optics, the human body and psyche, textures, and nature. (Shortform note: You can see the painting in high resolution here.) Francesco del Giocondo, an up-and-coming silk merchant, commissioned Leonardo to paint his wife, Lisa del Giocondo. Possibly, Leonardo agreed to paint her because she wasn’t a noblewoman, and he wouldn’t have to worry about traditional rules for portraits. (Shortform note: Francesco and Lisa never got their commission since Leonardo never turned in the painting. When he died, the portrait stayed in the possession of King Francis I.)
Leonardo applied everything he had learned over the years in this work of art, including these three key sets of insights that Isaacson identifies:
He applied his knowledge of optics in three creative ways:
1) He departed from traditional methods to take advantage of light and shade. Isaacson explains that Leonardo primed the painting with lead white, instead of the traditional mix artists used at the time. This reflected the light better, even from below the innumerable layers of oil, which added to the luminosity and depth of the painting. He also created shade in his subject’s face with a mixture of iron and manganese, another departure from tradition. This softly delineated her features and mimicked the texture of skin. (Shortform note: Leonardo’s unique mix of pigments allowed him to create the sfumato that characterizes his paintings. Scientists only recently discovered what those pigments were thanks to X-ray studies.)
2) He created an artificial source of light to highlight her features. The light in the painting should be coming from behind her, where the landscape is. However, Isaacson says Leonardo created an artificial light coming from the top left to illuminate her face but he did it inconspicuously so that it wouldn’t feel unnatural. (Shortform note: Unfortunately, the light in the real world has been less kind to the “Mona Lisa.” The cracks in her surface and the darkening of her pigments partly result from the lighting the painting has been under.)
3) He emulated how our eyes work to make the painting more lifelike. To mimic how the eye sees far away objects less clearly, Leonardo made the background diffuse while her hand and body were more clearly delineated. Then, Isaacson explains that Leonardo fixed her eyes on the viewer by playing with how our eyes process light and shades. If you look at a three-dimensional object from different angles, you see it differently, but this doesn’t happen in a two-dimensional plane. Thus, every time you look at her eyes, you see them fixed in the same position, apparently looking straight at you.
(Shortform note: A study suggests that Lisa is not, in fact, looking at you. According to measurements taken while volunteers looked at the painting, Lisa is looking over your right shoulder, not straight at you.)
The central element of the painting, Mona Lisa’s smile, is a product of Leonardo’s knowledge of optics, anatomy, and human emotion.
Isaacson reports that Leonardo had been dissecting and drawing human mouths, tracing each layer of muscle and thread of nerve. He then figured out which muscles and nerves created a smile, a purse of the lips, or any other movement of the mouth. In his notebooks, alongside different drawings of dissected mouths, there is a drawing of a smile that looks a lot like Lisa’s.
Besides in-depth knowledge of anatomy, Leonardo used optics to create Mona Lisa’s cryptic smile. Isaacson explains that Leonardo knew that the retina catches the light differently at different points of its surface, which makes the eye see things more or less clearly depending on the angle it uses. When you stare at something directly, you see it in more detail; when you look at it from the corner of your eye, you see the surrounding shadows.
Knowing this, Leonardo delineated her mouth clearly and used shadows to hint at a smile. Isaacson explains that, when you look at her mouth, you see the details but no smile; when you look anywhere else in the painting, you notice the shadows around her mouth and it seems like she’s smiling. Look back at her mouth and you lose her smile.
Using his knowledge of anatomy and optics, Isaacson argues that Leonardo created a smile that was representative of human emotion. It exists beneath the surface, not clearly delineated but shaped by the surrounding shadows. (Shortform note: Mona Lisa’s smile elevated the portrait from a regular painting to the most famous painting in the world. For the first time, people looked at a portrait and saw a real person with life in her expression.)
Embracing the aesthetic and spiritual aspect of the microcosm-macrocosm analogy, Leonardo made the landscape and Lisa become one. Isaacson explains that the paths and river behind her seem to flow into her with her hair and clothing following the same patterns. Besides the synchronic fusing of Lisa with the earth, the earth is a diachronic blend. Isaacson describes the river shaping the rocks, mountains, and valleys, while the bridge near her shoulder represents human history—all of it culminating in the young woman. (Shortform note: This was not the first time Leonardo used a sitter’s background to convey a history of creation. He accomplished the same effect, for example, in “Virgin of the Rocks.”)
According to Isaacson, the third element of Leonardo’s genius was the flaws that humanized him and gave his life and work a unique edge: perfectionism and a lack of discipline. The key result of his flaws were unfinished would-be masterpieces, a variety of engineering projects he designed but never completed, and several treatises he never published. In this section, we’ll explore two of his unfinished works: “The Adoration of the Magi,” and the horse monument. (Shortform note: Maybe Leonardo couldn’t complete many of his projects due to material constraints, rather than personality quirks. He relied on commissions to support himself, and those commissions didn’t fund his “passion projects,” including his engineering designs and treatises.)
In 1481, Leonardo began working on a masterpiece he would never finish: “The Adoration of the Magi.” Despite it being unfinished, Isaacson explains that Leonardo’s preparatory drawings (one of which you can see here) show that he was on his way to accomplishing something great:
1. He applied his studies of optics to the careful design of perspective, including the vortex that formed around the central figures: the Virgin and the child Christ. (Shortform note: Leonardo was fascinated by vortices. He found the shape in the movements of water, air, and blood—centuries before scientists could use advanced technology to identify it.)
2. He applied his talent for metaphor. The background showed a pagan temple being rebuilt, a metaphor for Christianity destroying Roman paganism and creating a new culture. (Shortform note: Experts argue that the metaphor goes deeper. The temple represents peace, while the battle on horseback in the background represents war. The palm tree in the middle symbolizes Christ’s suffering as the path from conflict to peace.)
3. He applied his talent for narrative. Through their actions, the characters surrounding the Virgin and Christ are telling the story of the epiphany: the moment they realized Christ was the child of God. (Shortform note: An important element of this narrative is the presence of two characters in the foreground, one in each corner of the drawing, looking out and gesturing with their hands to invite people to join in the moment of epiphany.)
Isaacson argues that Leonardo might have stopped painting because he imagined something more perfect than he could accomplish. There were over 30 characters in the painting, and each one had to cast shadows on the other 29. Likewise, each person’s emotions and actions had to be coherent with the others’. (Shortform note: When Leonardo failed to complete his commission, Filippino Lippi took it over. His work clearly takes inspiration from Leonardo’s preparatory drawings, but lacks the optics knowledge to ensure that each character would affect the light and shade on the characters surrounding them.)
In 1489, Duke Ludovico of Milan commissioned Leonardo to build a bronze monument in honor of his father, but Isaacson reports that both Leonardo’s creative process and Ludovico’s change of heart conspired to leave the work unfinished. Still, the commission elevated Leonardo to one of the duke’s favored artists. (Shortform note: Although Leonardo couldn’t finish his project, Nina Akamu finally brought his plans to life in 1999. You can see it here today.)
It was a challenging project, and Isaacson explains that Leonardo made it even more ambitious:
1. He planned to make the monument at least 23 feet high, almost two times taller than similar monuments Verrocchio and Donatello had created. (Shortform note: In fact, Leonardo advertised the monument as “the largest equestrian monument in the world.”)
2. He became fascinated with equestrian anatomy and decided to dissect a horse before he designed one. Through those studies, he even produced a treatise on horse anatomy and came up with systems to make stables more comfortable for horses (Shortform note: You can see part of Leonardo’s comparative studies of horse and human anatomy here.)
3. Usually, large bronze monuments were cast into separate pieces, then put together for the finished product. Leonardo, being a perfectionist, decided his monument would be cast in one piece. To achieve this, he devised a complex engineering system and made several experiments to find the right method and materials. (Shortform note: Leonardo’s plan to cast the monument in one piece didn’t pan out. Akamu, who built the monument in 1999, cast the monument into several pieces before melting it together.)
Unfortunately, Leonardo took too much time to make progress. Isaacson explains that, right as Leonardo was finally getting ready to cast the final monument, a war broke out. In 1494, France invaded Italy and Ludovico decided to use the bronze set aside for the monument to build cannons instead, in preparation for the imminent arrival of the French in Milan. (Shortform note: Leonardo held on to hope that he would at some point finish the monument, but that hope was finally quashed when Ludovico lost to the French and fled Milan in 1499.)
While Leonardo’s particular genius was unique, you can replicate it by nurturing the same natural inclinations and leaning carefully into the same flaws. To achieve this, Isaacson extracts lessons from Leonardo that you can apply to be more like the Renaissance genius:
Shortform Suggestions to Help you Apply Leonardo’s Lessons
These books from the Shortform library offer more guidance to follow Leonardo’s lessons:
In Big Magic, Elizabeth Gilbert explains that you can practice “gentle inquisitiveness” to see where your interests lead you and how they can feed your creativity.
You can follow the approach Scott Young outlines in Ultralearning to design a personal learning project about an interest you want to learn more about: Conduct meta-learning research, create a schedule, follow your plan, analyze your results, and create a follow-up plan to retain everything you’ve learned.
If you struggle with details, try doing one of your daily activities in slow motion, as Bhante Gunaratana recommends in Mindfulness in Plain English. Slow down to 10X the time it takes you to do an activity and pay full attention to each component.
The voices of critics can stifle your imagination. To make sure they don’t put out your creative fire, follow Stephen King’s advice in On Writing: Write (or do any creative activity) with the door closed, literally and metaphorically. This will help you block out the outside world and create for yourself, rather than worrying about what others think.
If you feel guilty about procrastinating and getting distracted, remember what Austin Kleon advises in Steal Like an Artist: The time you spend on hobbies and being bored improves your creativity because it encourages your mind to make new connections.
In Principles, Ray Dalio suggests keeping your eye on two hurdles for finding the facts: your ego and your blindspots. To avoid letting them get in the way, look at your mistakes as proof that you’re learning, and frame your search for facts as the search for the best possible answer, not for the best answer you can come up with.
You don’t have to be an artist to use visuals. In Make it Stick, Peter Brown, Henry Roediger, and Mark McDaniels explain that using illustrations and images helps you understand and retain new concepts. They also suggest examining multiple examples and problems at the same time to find common threads.
One way to make striving for perfection manageable is to ask yourself “How can I do better today?” As David Schwartz explains in The Magic of Thinking Big, this will prompt you to find daily opportunities for improvement. He also suggests seeking out collaboration by always asking more questions than you answer and by offering your views in the form of questions to elicit feedback from others.
Money didn’t dictate Leonardo’s passions, but it did dictate where his career could take him. To make sure you can build a career you love and also have a steady financial base, follow the eight steps Vicki Robin and Joe Dominguez outline in Your Money or Your Life: Understand the flow of money in your life, align your spending with your values and goals, graph and increase your income, cut spending, and invest.
In The Bullet Journal Method, Ryder Carroll also advocates for writing things down, even when technological alternatives seem more efficient. He argues that analog writing such as in a bullet journal can help you get organized, live in the present, find clarity on what’s important to you, and see your progress through time.
To tap into Leonardo’s appreciation for mystery, you might get inspiration from the Tao Te Ching, which explains that some things can’t be understood, only experienced. To engage with the inexplicable, keep your thoughts simple, be patient with others, and be compassionate toward yourself.
Isaacson extracts lessons from Leonardo’s life and work that you can apply to be more like the Renaissance genius.
List at least five topics you’d like to learn more about. Choose one to tackle first. Set time aside in your calendar for getting started, and write down the resources you have on hand (for example, books, a museum in your city, or an expert you can ask.)
Practice Leonardo’s systematic observation. Choose an object or phenomenon you’re interested in understanding better. Make a list of specific aspects of that object or phenomenon you want to observe. For example, if you’re interested in understanding how people interact with each other in a meeting, your list might include “How people interrupt each other, how speakers use eye contact, and how they signal agreement.”
Use visualization to find intersections between different topics. Choose a topic you’re interested in and write down how you will research it, whether it’s online, through books, or by asking experts. Next, create a mind map and add to it each new piece of information you learn. Highlight any intersections you find with other areas of knowledge. For example, you might start researching climate change, and find that science intersects with the economy, history, and anthropology.
Follow Leonardo’s footsteps and strive for perfection—but without letting it stop you from completing your projects. Think of a project you’ve put on hold, that you’re not sure how to approach, or that you’ve completed but aren’t totally satisfied with. Write down the opportunities for improvement that you see in the project. Next, choose one that you could tackle today. What is one small step you can take today to improve on it?