Leonardo da Vinci: lessons in curiosity, creativity, and cross-disciplinary thinking

Executive overview

Leonardo da Vinci's genius was not a gift — it was willed. Self-taught and excluded from formal Latin schooling, he became a disciple of experience over theory, developing an empirical approach that foreshadowed the scientific method by over a century.

His notebooks — 7,200 surviving pages, estimated to be only a quarter of what he wrote — are the greatest record of human curiosity ever created. They span engineering, anatomy, geology, art, water mechanics, and military invention, often on the same page.

What separated Leonardo from the merely brilliant was the ability to combine imagination with intellect across every discipline simultaneously.

Rejecting formal authority

• Born out of wedlock, he was not sent to Latin schools — an accident that freed him from traditional thinking.
• He called himself an "unlettered man" with irony, proud that his lack of schooling forced him into direct observation.
• His method: induce from experiments, then use reasoning to explain why the experience behaves as it does.
• "My subjects require experience rather than the words of others."
• His empirical approach foreshadowed Bacon and Galileo by more than a century.

The notebooks

• Over 7,200 pages survive — likely only one quarter of what he actually wrote.
• Pages held engineering drawings, costume designs, to-do lists, anatomy studies, and fable sketches — often crammed together on the same sheet.
• He rarely dated pages and often returned months or years later to add a thought, just as he returned to unfinished paintings.
• Good paper was costly; he used every edge and corner, jumbling fields deliberately.
• Paper has outlasted digital: Isaacson notes Leonardo's notebooks survive at a higher percentage after 500 years than Steve Jobs's emails from the 1990s.

Creativity and procrastination

• While painting the Last Supper, he sometimes arrived, applied a single brushstroke, and left. Other days he painted from sunrise to sunset without eating.
• He told the duke who commissioned the work: "Men of lofty genius sometimes accomplish the most when they work the least, for their minds are occupied with their ideas and the perfection of their conceptions to which they afterwards give form."
• Creativity requires time for ideas to marinate. Intuition needs nurturing.
• Procrastinating like Leonardo requires gathering all possible facts first, then allowing the collection to simmer.

Anatomy and scientific discovery

• From 1508 to 1513, Leonardo dissected approximately 20 bodies, beautifully illustrating every body part and limb — with no medical training, using basic tools, on rapidly decomposing cadavers.
• He documented arteriosclerosis: thickened, stiffened arterial walls from plaque accumulation — the first such clinical description.
• He used analogy to explain it: blood vessels behave like oranges, where the peel toughens and the pulp diminishes with age.
• His to-do list from this period included surgical tools, ink, charcoal, wax — and "describe the tongue of the woodpecker."
• He pursued the woodpecker because it was an exception: the tongue pushes rather than pulls, unlike every other muscle he had studied.
• He also noted the crocodile's second jaw joint, which produces 3,700 pounds per square inch of force — more than 30 times that of a human bite.

The microcosm and macrocosm

• Leonardo saw the human body as an analogy for the earth: bones are rocks, blood vessels are rivers, the ocean's tides are the world's breathing.
• "Man is the image of the world."
• His curiosity was not just about understanding things — it was about understanding how we fit into them.

Patrons and the world he moved through

• His patron in Milan, Ludovico Sforza, was ruthless; his next patron, Cesare Borgia — son of Pope Alexander VI — was murderous, incestuous, and the model for Machiavelli's The Prince.
• Leonardo may have gone to work for Borgia at Machiavelli's suggestion, designing military inventions.
• His plan to divert the Arno River from Pisa required moving a million tons of earth; he calculated man-hours using one of the first time-and-motion studies in history (25 pounds per shovel load, 20 loads per wheelbarrow, 540 men over 100 days).
• The project never came to fruition — as was true of many of his grandest schemes.
• "In order to be a true visionary, one has to be willing to overreach and to fail some of the time."

Leonardo and Michelangelo

• Michelangelo was 23 years younger, pious, celibate, often in rags, and contentious.
• Leonardo was flamboyant, generous, dressed in costume, travelled with young companions, and relished life.
• Michelangelo publicly mocked Leonardo over the unfinished horse monument: "So those idiot Milanese actually believed in you."
• Michelangelo once punched a fellow student hard enough to permanently disfigure his nose.
• Leonardo seemed to relish life; Michelangelo seemed constitutionally unhappy.

Principles distilled from his life

• Be relentlessly curious. He wanted to know why people yawn, how they walk on ice, what makes the aortic valve close. Curiosity was not occasional — it was constant.
• Seek knowledge for its own sake. He did not need to know how the heart valve works to paint the Mona Lisa. Pure curiosity widened the range of connections he could make.
• Go down rabbit holes. 169 attempts to square a circle. 730 observations on water flow across eight notebook pages. 67 words for different types of moving water.
• Avoid silos. His knowledge of how light strikes the retina informed the perspective of the Last Supper. Dissecting lips produced the smile of the Mona Lisa.
• Indulge fantasy. Giant crossbows, turtle tanks, ideal cities, man-powered flying machines. The imagination that produced unworkable schemes also produced inventions the world would build centuries later — scuba gear, helicopters, suction pumps.
• Make lists and put odd things on them. His to-do lists are among the greatest records of curiosity ever written.
• Take notes on paper. 500 years later, his notebooks astonish. Tweets and Facebook posts will not survive 50.
• Be open to mystery. Not everything needs sharp lines.