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Sample Chapter: Duly Noted

This is a sample chapter from Jorge Arango’s book Duly Noted: Extend Your Mind Through Connected Notes. 2024, Rosenfeld Media.

Chapter 1

Notes Are for Thinking

When I was a boy, the beginning of school was one of my favorite times of the year. One day always stood out: when my mom took me to buy stationery. I loved getting new pens, pencils, and notebooks. A fresh notebook held the promise of clarity, order, and better grades. I mostly used Mead Trapper Keepers, a popular brand of loose-leaf binders. They represent how I managed notes as a kid: I’d write down what I heard during class and stash pages in that subject’s section, in chronological order. While studying, I’d revisit those notes. Occasionally, I’d discard old ones to make room.

By the end of the school year, I had a binder full of transcripts. They’d served their purpose, so I could toss them. Next year would bring new teachers, new classes, and new notebooks. I seldom revisited old notes. This basic approach was the start of my note-taking life. I’ve since learned that notes can be more than a means for capture and recall: they’re also a medium for thinking.

What Are Notes For?

My Mac’s dictionary defines a note as “a brief record of facts, topics, or thoughts, written down as an aid to memory.” But as with other common words, “note” has more than one meaning. We also speak of some financial instruments as notes. And, of course, notes are also the stuff of musical melodies. But in this book, we mean the first usage: brief written records that aid our minds.

Not everything you write down is a note. For one thing, as the definition says, notes tend to be short. Think sticky notes, not essays. Intent also matters: you make notes primarily to aid your thinking. Sometimes you write notes for others, but most often you do so for yourself. Some notes you “dash off,” while others you ponder. Most aren’t meant for publication; I’ve made many notes while writing this book, but writing the book’s text is different from note-taking. All notes augment your mind in different ways.


Remembering might be the most common reason to take notes: you hear or see something you want to recall later. This is why, when you call a company’s help desk, the agent suggests you have a pen and paper at hand. It’s good advice: such calls yield case numbers, dates, and other details that you’ll forget quickly if you don’t write them down.


A common reason for taking notes is to recall what you heard during a lecture or video. For example, when attending a presentation, you may type into your laptop or scribble in your notebook. Doing so has a dual benefit: it helps you pay attention and produces a text that reminds you of what the speaker said.


Some professions, such as research scientists and medical doctors, benefit from keeping records of their work. This is a kind of remembering, but a bit more formal. It’s worth examining separately since such notes also provide legally admissible evidence when outcomes are contested. People in professions that require it take great care with their notes.


Sometimes you write things down not because you’re trying to remember a particular detail but because you’re trying to learn about a subject. Learning entails more than just remembering facts. For one thing, you must connect ideas at different levels of abstraction. For another, learning often happens in sessions spread over several days, weeks, or months, as in a class. Much of the note-taking discussed in this book focuses on learning.


When researching a subject, you want to recall the salient facts. And if you’re interviewing someone, you want to keep track of the most important things they said. In either case, you’re ultimately looking to synthesize what you learn so you can make better decisions. Notes aid the process.


Sometimes you take notes not to remember or learn something, but to generate new ideas. This is one of the most exciting uses of notes: your notebook becomes a collaborator in the thinking process. Putting thoughts down on paper (or on the screen) gives you fodder for reflection, leading to other ideas that you also capture.

You’ve experienced this when brainstorming using sticky notes on a whiteboard. Seeing notes on the board suggests other ideas. You move them around to form clusters, suggesting further ideas. A virtuous process follows.


Many people live by their agendas and bullet journals. When you have many things to do or track—as is often the case when managing long and complex projects—it helps to write things down. Sitting down with a calendar and a sheet of paper will help you plan more effectively than if you had to keep everything in your head.

Imagine you’re going on a trip, so you make a checklist of items to pack. Seeing items on the list will remind you of things you may have missed at first. You may also consider the priority of items on the list. (For example, your passport should probably be first.) Visualizing items and the relationships between them helps you prepare for the trip.


Although you take most notes for your own sake, you also leave some for others. For example, I sometimes find food containers in our refrigerator with a sticky note that says, “Papa, don’t eat!” My kids know that, without this note, their snack might soon be gone. This fits the definition of “brief record,” even if it’s not meant for “recall.” These notes turn your surroundings into shared cognitive environments.


While writing this book, I asked people on Twitter why they take notes. Bastiaan van Rooden memorably replied, “To slow down the monkey in my head.” I can relate: many people pay better attention when their hands are busy. In this case, the primary benefit of scribbling things down is keeping your attention focused; the marks on paper are a nice secondary benefit.

Note-Taking Media

Not only are there many reasons for taking notes, but there are also just as many different ways to do so. You can doodle with a pencil in a notebook, write with a marker on a sticky note, type into an app on your phone, draw with chalk on a sidewalk, or tie a string around your finger. In a pinch, you may even write on your skin.

While walking around Tahoe City, CA, my daughter saw a store she wanted to return to. Lacking paper, she wrote down its name on her hand.

Which is to say, you can make notes from whatever is handy—what matters is catching and preserving fleeting thoughts and observations. That said, it helps to be intentional: different note-taking media are suited for different needs.

Pen and Paper

There are good reasons why paper-based notes remain popular. With a bit of care, paper lasts a long time. Paper requires no batteries, and you don’t need a special app or device to read your notes; the paper itself is the medium. Paper is also portable and fast.

But paper also has its downsides. Copying paper-based notes requires specialized equipment (e.g., a photocopier) and lots of time. While notebooks are portable, large paper-based repositories (e.g., collections of notebooks) aren’t. You can’t search paper or link notes easily to each other. And with bound notebooks, you can only view notes in the order they were written. (Unless they’re indexed, which also takes time.)

Here is part of my collection of paper notebooks, spanning two decades. The only way I can find stuff in most of these books is if I know the date when I wrote the note.

Index Cards

Index cards are a convenient way around the constraints of notebooks. Since cards aren’t bound together, you can easily re-sort them. They’re ideally sized for note-taking: smaller than regular sheets of paper, but large enough to capture a single idea in some detail. And because they use thick stock, they stand up to manipulation.

You can use boxes to keep cards organized. When archived carefully, index cards provide one of the advantages of digital notes: random access. That is, you can jump directly to the note you need without having to flip through the rest. They don’t need to be stored in the order they were written; you can archive them alphabetically or in any other organizational scheme.

Because of this flexibility, index cards are a popular thinking medium for researchers and authors who keep and refer to lots of notes. Ryan Holiday, author of several popular books, says that his index card–based note-taking system:

has totally transformed my process and drastically increased my creative output. It’s responsible for helping me publish three books in three years (along with other books I’ve had the privilege of contributing to), write countless articles published in newspapers and websites, send out my reading recommendations every month, and make all sorts of other work and personal successes possible.

Holiday’s system consists of individual index cards with a single thought or quotation on each one. He writes a category label in the top-right corner of each card and stores these cards in one big box. But when working on a specific project, such as a book, he uses a smaller dedicated box for the project. Holiday learned this approach from his mentor, the author Robert Greene. Other authors, such as Vladimir Nabokov, also used index cards to organize their work.


Underlining key sentences and writing ideas on book pages is a common way of taking notes while reading. The obvious advantage is that note-taking happens in context: you capture ideas near (or on) the texts that sparked them, so they’re easier to understand later. But this is also their main downside: since they don’t stand on their own, these notes are harder to reorganize or relate to other notes.

E-books have an edge here. Digital marginalia can be more easily referenced, searched, backed up, and synced. But some people like to mark up physical books with a pen or highlighter. Many of the ideas in Holiday’s index cards come from his reading: he annotates books and articles as he reads them, marking passages that stand out and writing thoughts in the margins as he goes along.

Sticky Notes

Personally, I don’t like writing in books—but I still want the advantages of taking notes in context. Sticky notes provide a way around this dilemma: I read with a pad of small stickies and a pencil. Whenever I find an idea or passage that resonates, I write a few words on a sticky note and paste it on the book’s margins, so it protrudes from the page. In this way, it doubles as a bookmark.

Of course, sticky notes are helpful for more than annotating books. They’re also a mainstay of workshops, design studios, and other situations that require groups of people to think together. Using sticky notes, it’s easy to turn walls, whiteboards, windows, tabletops, and other ordinary surfaces into temporary placeholders for ideas. (More on this in Chapter 10, where we’ll discuss collaborative note-taking.)

Sticky notes’ main advantage is that they can be attached and reattached nearly anywhere on a smooth surface. Because of this, they’re ideal for exploring relationships between ideas. You can paste notes in any sequence and reorganize them later. That said, larger sticky notes aren’t suitable for storing ideas long-term; it’s impractical to keep walls and whiteboards covered in notes. (Of course, this doesn’t apply to the small sticky notes used to annotate books.)


One way to get around sticky notes’ ephemeral nature is to take pictures of the wall or board before taking down the stickies. While photos aren’t strictly about making marks, they can be an effective way of capturing ideas and observations. For example, whenever I park in a large, unfamiliar parking lot, I take a photograph of a nearby landmark so that I can find my car later.

I took this photograph in the parking lot of Disney’s Animal Kingdom theme park. Note I didn’t bother with proper framing; I didn’t expect to use this photograph for anything other than finding where I’d parked.

People used cameras as note-taking devices well before personal computers arrived on the scene. Around the mid-Twentieth Century, film-based cameras got small, fast, convenient, and inexpensive enough to serve effectively in this role. In a presentation to shareholders, Polaroid founder Edwin Land described the original (1944) concept for instant photography as

a kind of photography that would become part of the human being, an adjunct to your memory; something that was always with you, so that when you looked at something, you could, in effect, press a button and have a record of it in its accuracy, its intricacy, its beauty—have that forever.

The main advantage of photographing things you want to remember is convenience. You likely have a phone with an excellent camera in your pocket; no note-taking method is faster than taking it out, pointing it at something, and shooting. The obvious downside is that you’re limited to capturing what you see in the world—great for remembering where you parked, but less so for recalling abstract ideas.

Audio and Video

One way to remember what you were thinking is to record yourself saying it. Recording equipment used to be fiddly, bulky, and expensive, but smartphones have made recording ubiquitous. Software can transcribe your recordings so you can read and search for what you said.

Recordings are most effective at capturing what somebody says with high fidelity. While you may lose some thoughts when handwriting or typing notes, a recording will capture everything verbatim. This is also its downside: recordings don’t benefit from the real-time synthesis you do when using a slower medium. Still, some people love to record themselves “speaking their minds.”

Digital Notes

Most of the note-taking means we’ve highlighted so far existed in some form before computers. But now, we’ll focus specifically on digital note-taking. Almost five billion people have a smartphone, and many also use laptop or desktop computers. Most of these devices include note-taking apps, and people use them to write down all sorts of things, ranging from shopping lists to book notes.

Many digital note-taking applications mimic the abilities and superficial characteristics of analog (i.e., “real-world”) note-taking media. For example, Macs include an application called Stickies that lets you place sticky notes on your computer desktop. Well, not really: Stickies places a series of pixels that look like sticky notes on another series of pixels that function like a “desktop.”

WORKING NOTE: Install Obsidian

In the late 2010s and early 2020s, new digital note-taking tools appeared that brought to market capabilities previously available only via specialized software and often in research contexts. Several are worth exploring and investing in. But to make the ideas in this book more tangible, we’ll focus on one such tool: Obsidian.

Obsidian is a commercial software application created by a small team. As of this writing, it’s free for personal use and available on all major desktop and mobile computing platforms. It embodies key principles we’ll explore in this book, so it’s a great tool for learning. That said, you could use other tools to implement these practices. We’ll just focus on Obsidian for illustration.

(If you’re already using Obsidian or a comparable note-taking app, feel free to skip the rest of this section.)

To start, download and install Obsidian on your computer or mobile device. If the former, you can install it by visiting and following the instructions. If the latter, you can search for Obsidian in your device’s app store and install it from there.

Obsidian’s first screen gives you several options. If you’re using the software for the first time, you can either select Quick Start or Create a new vault. (The other options are mostly for use by existing Obsidian users.)

When you first launch Obsidian, you’ll have the choice to create a new vault. In Obsidian, a vault is where you store notes. You can create and manage as many vaults as you want. For example, I currently manage two vaults: one where I manage projects and another that serves as my primary long-term knowledge repository. To use Obsidian, you must create at least one vault.

Under the hood, a vault is simply a folder on your computer containing plain text files. So, if you decide to move on, you can still access your data in a universally compatible format. Go ahead and create your first vault and look around Obsidian’s user interface. In the next chapter, you’ll create your first note. But for now, just become familiar with the software.

After you create your first vault, Obsidian will open without any note selected. This is understandable since you haven’t created anything yet.

Obsidian’s user interface has a panel on the left that lists your available notes and a panel on the right that shows the currently open note(s). The parenthetical plural is because Obsidian lets you open several notes simultaneously, which you can view either in tabs or side-by-side.

Think of a typical war movie scene: a ragtag platoon planning an attack. The soldiers huddle close to the ground and, absent paper and pens, draw (literal) lines in the sand and move rocks and twigs to represent targets and units. The commander might say something like, “Hutch, you and Charlie stand here and give cover while Mack and I rush the compound.” One soldier might ask a question, and another will contribute an idea—all facilitated by a few rocks and dirt.

The improvised map gets the platoon “on the same page,” so to speak. By representing the battlefield as tangible things they can manipulate, they can better think through and communicate their plans, spotting obstacles and opportunities they might miss if they were trying to imagine the situation in their heads. You may have had similar experiences when working with colleagues around a whiteboard.

Once you understand that you think with things, you can explore ways to augment your thinking. The battlefield map and the whiteboard are examples of augmentations that are useful when collaborating with others. Notes are a similar augmentation. As with the whiteboard, you can use them to think collaboratively, but they’re also very useful when thinking by yourself.

In Genius, his biography of Richard Feynman, James Gleick writes about the role of notes in the physicist’s work. Starting from an early age, Feynman worked out problems in his notebooks. Later in life, in an interview with MIT historian Charles Weiner, he explained the role of his notes. Gleick writes,

He began dating his scientific notes as he worked, something he had never done before. Weiner once remarked casually that his new parton notes represented “a record of the day-to-day work,” and Feynman reacted sharply. “I actually did the work on the paper,” he said. “Well,” Weiner said, “the work was done in your head, but the record of it is still here.” “No, it’s not a record, not really. It’s working. You have to work on paper, and this is the paper. Okay?”

To emphasize the point, notes aren’t merely a way to record your thinking; they’re part of where thinking happens. They are the means through which you understand and make sense of things. When making notes, you’re thinking on the page and beyond, experimenting with temporary models that describe how a part of the world might work. It’s a creative, generative act of discovery and clarification.

NOTABLE NOTE-TAKER: Gretchen Anderson

Gretchen Anderson is a product consultant, coach, and author based in the San Francisco Bay Area. While working on her book Mastering Collaboration, Gretchen built an outline using her computer. She used this outline to think through the high-level ideas in the book. However, the outline became constraining as she got into the details. “I started to lose track of it,” she explained. So, she switched to using physical sticky notes:

I was doing this at home, where I don’t have a whiteboard…But I do have lots of windows, so at one point, I busted out the sticky notes and had the medium-sized ones and one color for chapters and smaller different colored ones for main points and the stories that would buttress them so that I could create that kind of map that I could see all at one time. Interestingly, that happened late in the process, maybe three-quarters of the way through. You know, I was kicking myself like, “Gretchen, you know that you could have done this earlier!”…I probably couldn’t have done it any other way. I started out with an outline, I changed that outline to be something that was looser so that I could fit everything I was learning into it, and then I needed to kind of remix it again to make it something that people could follow and not just have it be a laundry list of stuff I learned.

By commandeering her walls and windows, Gretchen literally expanded her thinking surface. Moving from an outline to a two-dimensional map of ideas allowed her to see everything at once and “remix” it into a sequence that her readers could follow. Note that she used sticky notes of different colors and sizes, which allowed her to distinguish different structural elements at a glance.

Outlines are great for exploring hierarchical relationships, but not as effective when you want to visualize lots of stuff at the same time. Switching how you’re taking down ideas is a common way to get unstuck in complex creative projects. Different media have different capabilities and constraints: it’s important to be aware that you might have to switch at some point depending on what you’re doing.


As you see, there are many ways of taking notes and many reasons for doing so. But ultimately, you do it to extend your cognitive abilities. Thinking clearly is fundamental to everything you do, so mastering notes will help you in many aspects of your life.

As I mentioned in the introduction, this book focuses on digital note-taking. We’ll look beyond comfortable metaphors to new means of exploring ideas that are only feasible with computers. You’re not building a better Trapper Keeper, but something entirely different and more exciting. But I’m getting ahead of myself. Before you start building your note-taking system, you need to cover a few fundamentals.

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