Leonardo da Vinci’s Notebooks: What His Journals Reveal

Leonardo da Vinci’s journals – often called notebooks – are the bound pages where he recorded observations, inventions, drawings, and questions across art, anatomy, and engineering. They matter less as finished books and more as a lifelong habit of writing to think.
Despite being most well-known for his paintings, as time passes, his true legacy has become his journals (aka notebooks) – so much so that Bill Gates bought a collection of them for $30 million. Unlike Bill Gates, I don’t have millions of dollars to buy da Vinci’s original journals, but I did still spend the currency of my time reading his biography and observing his journals so I can improve my habit of keeping journals — part of my ongoing series on the journals of successful people.

Now, wanting to understand how da Vinci kept his journal may, at first, seem as pointless as trying to clap with one hand. I mean, how do you try to emulate the journals of someone who is synonymous with genius?

However, I do think the observation can still bear fruit, even if you and I don’t have the intellectual gifts (or interest) to paint like him. The way he used and kept his journals suggests that he certainly did something right, so there’s merit in trying to figure out what that was.

Key takeaway: Leonardo’s notebooks work because he treated curiosity as a daily job: observe closely, draw what you see, and let unrelated subjects collide on the same page. The habit to steal is not genius – it is unfinished, specific noticing.

Lifetime of Da Vinci’s Journals

Leonardo left an estimated 20,000-28,000 pages across about fifty notebooks – painting, engineering, anatomy, and whatever else pulled his attention that day.

It is estimated that da Vinci produced between 20,000 and 28,000 pages of notes and sketches spanning 50 different notebooks covering whatever topics interested him – painting, engineering, philosophy, warfare, physiology, landscape, proportion, perspective, geography, geology, light and shade, inventions and various other topics.

From records available to us, it is known that he started keeping journals when he was 26 years old and continued to write an average of 3 pages a day until the age of 67 in 1519.

Across his sophisticated sketches and backward-written entries, I could sense da Vinci’s obsession with figuring out the dozens of topics that fascinated him. More importantly, no other entry states that obsession as directly as this passage from his journal:

“What is fair in men doesn’t last. Old age creeps up on you. Nothing’s more fleeting than the years of a man’s life, but there is time enough for those who know how to use it. What’s the point of passing the Earth unnoticed? A man who does not become famous is no more than wood smoke on the wind of foam upon the sea, but I intend to leave a memory of myself in the minds of others.” – Leonardo da Vinci, discipline of experience

Where Leonardo’s Notebooks Are Today

Leonardo mostly wrote on loose sheets that were folded, shuffled, and bound into codices after his death, so today his notebooks are scattered across about a dozen collections in Europe and one private owner.

Leonardo probably did not keep “notebooks” in the way we picture them. According to the Victoria and Albert Museum, he worked on loose sheets bought from Milan’s stationers and carried them with him; the sheets were folded into booklets and bound later, possibly under the sculptor Pompeo Leoni, who owned much of the material in the decades after Leonardo died in 1519. That is why the surviving volumes are not in any logical order, why a single page can jump from hydraulics to hats, and why the estimate of what survives – most often put at around 7,000 pages, as in Walter Isaacson’s 2017 biography – is so much smaller than the total he is thought to have produced.

The main collections:

• Codex Atlanticus – Biblioteca Ambrosiana, Milan. The largest single collection, over a thousand sheets assembled by Leoni.
• Codex Arundel – British Library, London. A bound miscellany of some 280 sheets on mechanics, geometry, and much else.
• Codices Forster I, II, and III – Victoria and Albert Museum, London. Five small notebooks bound into three volumes; the only ones you can leaf through page by page online in the V&A’s viewer.
• The Windsor folios – Royal Collection, Windsor Castle. Around 600 sheets, including most of the anatomical drawings.
• Manuscripts A to M – Institut de France, Paris. Twelve notebooks taken to France in the Napoleonic era.
• Madrid Codices I and II – Biblioteca Nacional de España. Lost for centuries and rediscovered in 1965, misfiled.
• Codex Trivulzianus and the Codex on the Flight of Birds – Castello Sforzesco, Milan, and Biblioteca Reale, Turin.
• Codex Leicester – privately owned by Bill Gates since 1994; the only major codex not in a public institution, though it travels for exhibition.

For a journal keeper the interesting part is not the geography but the method it reveals: Leonardo did not wait for the right notebook. He wrote on whatever sheet was in his pocket, and the binding, ordering, and preservation were other people’s work, done later. The size of the journal mattered less to him than having paper within reach.

Observations from Da Vinci’s Habit of Keeping Journals

The useful part of studying Leonardo’s notebooks is not worship – it is noticing habits you can borrow: curiosity across subjects, drawing as thinking, and writing for yourself first.

Having had a glimpse of his intrinsic desire to be remembered, I think it is now worthwhile to extract learnings from the creation of his desire – the journals.

Leonardo spent most of his life as an engineer and architect – but what can be observed from his journals is that he used them as a tool – a means to an end for mastering of the problem at hand. So regardless of which stage of life you are in – parent, student, intellectual, or soul-searching – you can and should use the journal similarly and, like da Vinci, adjust the journals with your changing interests. I saw the same instinct in the one notebook Antoni Gaudí left behind – an architect using the pages to work out both his buildings and the life he wanted.

As I studied his large collection of journals, I took notes whenever I came across factors that I thought were fundamental to his habit of keeping journals. Then, I tried to synthesize these observations and notes into several methods or behaviors that appear to have enabled both da Vinci’s discoveries and his deep understanding of his topics of interest – all with the help of keeping such fascinating journals.

1. Creation comes from an obsession with making progress

“Lying about in bed never bought anyone fame. You got to get up and work” – Leonardo da Vinci

Above all other observations, it is important to note that it was not an explicit goal of Leonardo da Vinci to have such detailed journals, but it was rather his obsession with solving the problem and figuring things out, which implicitly resulted in such in-depth journals.

For anyone who keeps or wants to start a journal, it is extremely important to know their “why” because without it the habit of keeping one will not last very long. For Leonardo, it was his intention to “leave a memory of [himself] in the minds of others” in search of a deeper, more lasting meaning to his life.

2. Be curious about more than one subject or interest

“The noblest pleasure is the joy of understanding.” – Leonardo da Vinci

As I kept progressing through his journals, it was fascinating to observe how he was bringing together various interests and subjects in his work. For example, in his entry on Vitruvian Man, he used mathematics, proportions, and anatomy to reach the epiphany – subjects which he had explored before in separate journals.

Likewise, he used painting to understand nature, asking questions such as: Why is the sky blue? What effect does light have on the sky? How do muscles expand and contract, and how does blood circulate through the human body? He even questioned religion (I don’t imply anything religious here other than the fact that he was curious about it).

This has encouraged me to more deeply explore topics that I write about here on the forever learning journey. I hope to improve my sketching skills (currently I can only doodle), acquire more technical skills to build products, and try my best to bring various subjects and interests together to create unique works.

3. Visualize with a pen and paper to bring your ideas to life

Leonardo explicitly said that drawing or painting was a tool that he used to better understand the big picture – a means to an end. As a matter of fact, he only produced 20 paintings (or works of art) before his death, but he produced hundreds of sophisticated sketches in his private journal in his attempts to visualize them. Frida Kahlo blurred that line even further – in her illustrated diary the drawing and the writing run into each other on the same page.

It was his drawings and sketches that, after his death, served as an inspiration for others to understand and benefit from his inventions.

I often find myself constrained by only using words to write in my journal or on this blog – at most I have tried some simple doodles. I have made it a future goal to improve my sketching skills and use them to better translate my ideas onto paper. I hope sketching can help me visualize outcomes such as room designs, software product designs, drawings for relaxation, and much more. The same drawing-to-learn habit shows up in E.H. Shepard’s sketchbook work for Winnie the Pooh, where he kept drawing a real bear from life until the shape was right.

4. Work and journal genuinely for your intrinsic self

It has always remained a mystery as to why Leonardo made little effort to publish his work. Was he being secretive or waiting for the right moment?

For the purposes of this article, I won’t go into the argument over whether he should have published his work for the greater good of society, but from my analysis of his biography and meticulous nature of his journals, I’m convinced that they were written by a man who was genuinely and intrinsically driven to do great work. No other quote captures that better than what he reportedly said on his deathbed:

“I have offended God and mankind because my work didn’t reach the quality it should have.” – Leonardo da Vinci, on his deathbed.

Furthermore, his biography describes multiple occasions when he accepted commissions without finishing them—sometimes never producing the work and even moving to another city in the midst of a project. Thus, for much of his career, he depended on the kindness of patrons – the ruler of Milan, Ludovico Sforza, and then the French king, Francis I. Neither factor is characteristic of a man driven by external rewards or his career; instead, both suggest that he was intrinsically driven to produce work.

5. Break down complex ideas until they are simple

In his journals, he would pull apart complex machinery and explain each component separately—like a map that makes a complex puzzle more approachable. In the entry below he does exactly that for a hygrometer – a device used to measure moisture:

It is encouraging to know that even though his inventions were complicated, the process used was simple and can be replicated by others who are trying to work on something complicated – an invention or a personal roadblock that needs to be written out.

I have found this technique very helpful as the mind has the tendency to fear the unknown. By putting the whole idea on paper, you can force your mind to work on it step-by-step. Regardless of how many years pass by, this practice of breaking things down is central to how I work and is how I broke down the work required to study his journals and writing this article.

6. Ask questions, act, and experiment to create

“Educated men will look at what I do and say this is useless work. But the words they breathe from their mouths, are as wise as the winds they pass from their asses. Fools.” – Leonardo da Vinci

As a self-educated man with little to no formal schooling, he taught himself how to learn – a significant advantage over kids who were taught how to learn by others. Thus, he developed a revolutionary way of thinking – real-world application, experimentation, parallel thinking (he compared the flow of water to hair), understanding, and questioning:

Leonardo da Vinci – comparing hair and water in his attempt to understand flow of water.

Some notable questions I found interesting in his journals were:

• Why does it look like that? How does it work?
  
• Why is the sky blue?
  
• Why does a dog sniff another dog’s behind?
  
• What makes a face beautiful?
  

As I continue on a “forever learning journey” of self-education, his way of thinking inspires and reminds me to focus more on the fundamentals and ask questions like a child.

Improvements to Da Vinci’s Habit of Keeping Journals

Leonardo’s notebooks are not a perfect system. A few gaps – unfinished threads, hard-to-search pages, little review ritual – are worth noticing so you do not copy the myth along with the method.

However, while taking notes, I also observed some things that da Vinci did not do well—a point often ignored because of outcome bias. People often avoid criticizing the bad habits of successful people because they believe that “the ends justify the means.”

In summary, two improvements could have helped his work “reach the quality it should have”:

• Focus on and complete a topic or invention he began exploring.
  
• Publish and share his journals with the public to advance society.
  

As simple as they sound, these improvements are much harder to follow in practice. I give him credit for the projects to which he did give his best effort, because perhaps the others would not have succeeded if he had not moved on from previous projects.

Keeping Journals like Da Vinci

You do not need fifty notebooks to journal like Leonardo. You need a page that catches what you are actually curious about today, even when it does not look like “productive” writing.

The work produced in his journals cannot be entirely separated from who he was. Was his meticulous and detailed journal a result of his intrinsic motivation or intelligence or both? Did his ability to think by asking fundamental questions come from his self-education? Could he have achieved more fame through the work in his journals? I’m not sure there are any clean answers to any of those questions.

What is clear, however, is Leonardo da Vinci’s intrinsic desire to produce quality work and search for a deep and fulfilling meaning of his finite life. Thus, even if Leonardo da Vinci’s genius and works may lie outside the reach of most of us, his curiosity, focus, and journaling habit are still worth emulating. It’s a pattern that came up again when I later studied Albert Einstein and Thomas Edison — both were equally committed to using their journals as a place to think, not just record. For a modern clarify-before-clever protocol based on Einstein’s pages, see the Einstein notebook writing method.

If da Vinci’s notebooks made you want a lighter modern habit, get the free Journaling Habit newsletter with short experiments you can try the same day.