Recently I came across a video on youtube, that was titled ‘create a second brain in one hour’. I thought “what AI is he coding?”. First I was a little disappointed that it was not about coding but an application called obsidian. However I liked the idea of taking the nodes linking them around, follow backlinks and sync between devices and more.

This video got me hooked on the topic of note taking and in this article I want to share what I have leaned. I am not jet an article on note taking, but I think by showing how different note taking techniques relate to each other this can still be valuable for you.

tldr: It is about zettelkasten method, second brain, smart note taking, O/E/C method and connecting notes/ideas.

zettelkasten method

The Zettelkasten method became popular from the german scientist Luhmann. He organized facts he leaned over a time of more than 30 years on over 90 thousand index cards.

In the zettelkasten method, you first collect notes in the form of fleeting notes or reading notes.

  • fleeting notes are ideas that randomly sprang into your mind or a random information that you encountered. from radio, a conversation or as it is often called “under your shower”. I would also say that meeting notes are a kind of fleeting note.
  • reading notes are notes you take while reading/working through a book.

In regular intervals, you review your pile of fleeting and reeding notes. In this process you want to transform them into permanent notes.

  • permanent notes are notes you put more effort into, in making them independent and clear.
  • you keep permanent notes in your zettelkasten. and you sort them to the appropriate position, give them an identifier.

Once the permanent note is created, and put into position, you reference it from reference cards.

  • reference cards are common topic or project cards. You find the right reference card, by asking yourself the question “in what situation do you want to find this permanent note”.
  • reference cards can also reference each other.
  • and you can add references to a permanent note also to other permanent notes that are related.

One important feature of any card is, is that the index card is only this small. So to express an idea you have to think how to keep this idea small. In cases that your idea is to big, it is likely that is actually multiple ideas. By breaking down large general ideas, helps you to untangle a thought.

second brain

The second brain comes from the picture when you have lots of notes linking to each other. This picture can be visualized by computer programs such as roam research or obsidian. The advantage of these apps comes when navigating within your notes. because when adding a reference, the applications can also show backlinks. Meaning a list of cards that reference the current card.

Mostly I think that the word second brain just sounds very cool and interesting. I mean it worked. It brought me into the note taking.

smart note taking

Smart notes have 2 attributes, they are active, atomic and connected. I think these attributes are defined in the book “how to take smart notes”. I ordered it. But even after a week it did not get delivered. The information in this chapter I got mostly from Vicky BEEAMP's youtube channel (link below).

1. active

I found the the OEC method quite practical. To create notes from a book. find a question, mark examples (evidence) and write down the conclusion. With a question mark, a dot(.) and a minus(-) it is quick and easy to mark those on the side in the book.

Each question, each evidence and each conclusion can become its own note. These notes get connected/linked to each other. And then they can each link to existing other notes in the zettelkasten. And you can add links to them to notes that are already in the zettelkasten.

2. atomic

Each note should only express a single idea. When the note gets to big, you can likely split it to multiple independent notes. This allows that really each idea can be linked to and from. For example, an example, a story from a book, could be good to be linked from multiple questions. You decide if the different connections make sense to you.

3. connected

As mentioned before, notes should be linked as much as possible (but always with a reason) to other ideas. When searching for good other notes to link the new note to, you can ask yourself the following questions:

  1. where is this idea from? a book, person, song/movie, show …
  2. what other idea is similar to this one? What ideas handle a similar topic?
  3. what is the opposite? or What contradicts this idea? When does this idea not apply or what are its limitations?
  4. Where does this lead to? What situations can this idea be applied to.

note taking in for professionals

difference to client meeting notes

  • notes
  • conclusions
  • my todo’s
  • client todo’s


  • firm learning: How to Take Notes for Work
    • Vicky BEEAMP: How To Take Smart Notes (3 methods no one’s talking about)
  1. 1. zettelkasten method
  2. 2. second brain
  3. 3. smart note taking
    1. 3.1. 1. active
    2. 3.2. 2. atomic
    3. 3.3. 3. connected
  • note taking in for professionals
  • sources