Building a Second Brain

Building a Second Brain

by Tiago Forte

Building a Second Brain provides a revolutionary process for systematically collecting, storing, organizing, and combining digital information, knowledge, ideas, quotes, and notes based on the C.O.D.E system. Through this book, you’ll learn how to be more productive and organized. Most importantly, you’ll realize that what we create afterward can significantly impact the world.

Summary Notes

About The Second Brain

“This digital commonplace book is what I call a Second Brain. Think of it as the combination of a study notebook, a personal journal, and a sketchbook for new ideas.”

We live in a time when we are constantly bombarded with digital information. If we don't know how to select and organize all that information, we will get stuck in a creative crisis. To solve this, we can use a Second Brain - a knowledge management system; a defined way to collect, select and use information in a standardized way.

In the past, various scientists, writers, artists, and prominent historical figures used a notebook called "Commonplace book" to collect and reuse knowledge. They would save other people's thoughts, ideas, quotes, and scientific facts before writing their own reflections and combining them all to create something new. The Second Brain is a digital and improved version of this book. 

At the center of the Second Brain is the CODE system, consisting of a four-stage process: Capture, Organize, Distill, and Express. This system allows us to create a private collection of knowledge, select the most valuable information (Capture), organize them (Organize),  extract the key points out of captured notes (Distill), and use it to maximize our productivity and creativity (Express).

The Second Brain is built through all the tools and digital applications you use to interact with information, such as your calendar, to-do list, email, applications for reading books, etc, but the most important tool is your notetaking app. 

You can select the best app based on your notetaking style. There are four styles: 

  1. The Architect - Architects prefer organizing, inventing, and using their own systems. They benefit from notes software that enables them to create, tweak, and implement their own structures quickly. Recommended: Notion or Craft.

  2. The Gardener - Gardeners prefer linking their ideas and expanding their concepts. Such people need note-taking applications with a bottom-up approach where ideas and connections can occur and connect naturally. Recommended: Obsidian or Roam.

  3. The Librarian - Librarians love to make lists and compile a database of useful resources. Note-taking apps that have a simple format and allow quick retrieval of their notes are good for them. Recommended: Evernote or Microsoft OneNote.

  4. The Student - Students use the notes for short-term goals, such as writing a paper or taking a test. Recommended: Apple Notes or Google Keep.

Actions to take


“Knowledge capture is about mining the richness of the reading you’re already doing and the life you’re already living.”

When researching a particular topic, we come across a ton of information online, in books, articles, and scientific research. Due to the scope of information, we often save excessively long texts in our notes. This causes information overload, which only confuses us. 

Capturing is about keeping only essential passages from the source we read, the information necessary for our business or personal projects. To know what is essential, we must capture only the information that resonates with us—the ones that awaken the feeling of excitement, motivation, and curiosity in us.

The "12 favorite problems" strategy is another way to determine what is genuinely essential to us and what we need to capture. Favorite problems are those that we enjoy solving and that spark our curiosity. Some examples of these are:

  • How can I enhance my health?
  • How can I build close relationships?
  • How can I be more productive?
  • How can I create good habits?

Searching for the answers to these sorts of questions is a constant, evolutionary process as you’ll always be coming across new bits of relevant information. Start by making a list of your favorite problems, and use that as a guide for what sort of information you should capture.

Actions to take


“The next step in building your Second Brain is to take the morsels of insight you’ve begun to capture and organize them in a space where you can do your best thinking.”

Capturing information is easy. The more difficult part is organizing all the highlights we’ve collected so we can easily find the information when we need it. That’s why we need an excellent digital organizing system to solve this. 

The P.A.R.A system is a digital organizing system that sorts information into four categories:

  1. Projects -  In which project would this information be useful? If it doesn't fit any current project you are working on, go to the next step;

  2. Areas - In which life area should I place this information? It could be in a work area, ​​creativity area, ​​health area, etc. If you still can't find a place, go to the next step;

  3. Resources - In which resources should I record this information? If it still does not belongs there, then;

  4. Archive - Save the information in the archive. Later, you can move some files from the archive to some project or resource.

Actions to take


“Progressive Summarization is the technique I teach to distill notes down to their most important points. It is a simple process of taking the raw notes you’ve captured and organized and distilling them into a usable material that can directly inform a current project.”

Once we’ve captured and organized our notes, we need to summarize them and save only what’s absolutely essential. We can use the Progressive Summarization technique to do this, which consists of four stages: 

  1. Extract essential parts from our source;

  2. Bold the most important aspects of the extracted text;

  3. Go further and highlight the most important of the bolded text;

  4. Write a few of your insights on the subject.

By progressively extracting the most important information from the essential ones, the raw notes become processed, short, concrete materials we can easily work with.

Actions to take


“The final stage of the creative process, Express, is about refusing to wait until you have everything perfectly ready before you share what you know.”

The three previous steps in the C.O.D.E system lead to the end goal of using all the gathered and organized resources to build something new and share it with others. This new creation could be a blog post, an online course, a presentation, a book, or a YouTube video. 

The first step to creating them is similar to how we build a house - we need building blocks first. With Second Brain, it's easier than ever to get them; our captured and organized notes will be our creative building blocks. 

For example, we can use a list of quotes from some book, a list of notes from a business meeting, web clippings, notes from one of your projects, or a list of our reflections on some topic as a creative building block. Once we find these building blocks, it’s time to combine and share them.

Actions to take

Accelerate Creative Process

“Your Second Brain is a powerful ally in overcoming the universal challenge of creative work—sitting down to make progress and having no idea where to start.”

Every creative process is a mixture of divergence and convergence. There’s a divergent, spontaneous, and chaotic phase of creating new ideas that converge when the excess is removed to leave only the necessary. 

Many people get stuck at the divergent stage where they just collect and organize new information. The problem is they don't use the collected information to create something new and be productive; instead, they simply accumulate it. 

Being productive requires us to move to the convergence phase, meaning being able to use our collected information to create something new out of it. This can be done by closing the door to new ideas, working only with a few selected notes, distilling them, and creating something out of them.

Three methods can help us move more quickly from divergence to convergence: 

  • The archipelago of ideas - a method where we make a specific chain of ideas gathered during the divergent phase and then connect them with similar content. This can be done by first choosing the ideas and points you want to include in your outline and then arranging the sequence in a logical order. This method is best used when starting a project because it provides us with a series of small stepping stones rather than sitting down on a blank page and worrying about where to begin.
  • Hemingway's bridge - a method inspired by the way Ernest Hemingway in which you will build a bridge between the work you do today and the work you will do tomorrow by working on an outline of your project until you can clearly see the next step. This method is intended to keep a workflow so that even if you leave your work unfinished today, you will still know what to do tomorrow and how to progress.
  • Reducing the volume of information - removing excess information and creating shorter versions of notes. Shorter notes make it easier for us to browse a Second Brain, find the information we need more quickly, and be more productive.

While these are three different methods, combining them when working on a project is recommended for the best results.

Actions to take

Become A Good Digital Organizer

“Being organized isn’t a personality trait you’re born with, nor is it merely a matter of finding the right apps or tools. Being organized is a habit—a repeated set of actions you take as you encounter, work with, and put the information to use.”

Collecting and using knowledge to create something valuable is similar to a chef's job. Chefs also receive a lot of information, are given many tasks, have short deadlines for execution, and are required to ensure that the final product is high quality. 

Excellent chefs use the "Mise en place" technique, allowing the organization of tasks even during busy workdays. They do not allow disorder and chaos to be created during work, so they designate a place for everything from ingredients to equipment. 

We can adapt this to our Second Brain by following the P.A.R.A system and putting each piece of information in its place while we are working. 

Besides the "Mise en place" technique, these are a few more habits you can adopt to keep your Second Brain functional:

  1. Project checklists - creating and following the same checklists of tasks you always perform when starting and completing the project.

  2. Weekly and monthly reviews - periodically reviewing your projects and deciding on possible changes.

  3. Noticing a way to improve your Second Brain - noticing ideas worth keeping in notes and figuring out how to move or reorganize notes to make them more useful.

Actions to take

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