In the past three months, I posted my weekly discoveries on Fridays. It was a period of intensive learning. The experience convinced me of the benefit of taking notes, explaining learnings with one’s own language, and linking the notes. Now it is time for something new.

I draw positive conclusions from the experience of reporting weekly discoveries with me and go on to the next phase. Instead of collecting and report new things every Friday, I will focus on synthesizing links between the knowledge and ideas that I collect. The saved time of Friday writings will be spent on publishing in-depth blog posts (so please stay tuned), and on my teaching and writing project on applied mathematics and informatics, i.e. multiscale modelling, in drug discovery.

Nevertheless, in this last post of Discovery Weekly in its current form, I do want to report a recent discovery: the Zettelkasten system of knowledge management.

Starting from last week, I started taking notes using the Zettelkasten method, which I noted in a previous Discovery Weekly. The basic idea is to keep notes in zettel, a slip (piece of paper) or a plain-text file, and linking the notes with each other. It was developed by Niklas Luhmann, a sociologist who covers a wide area of research and was extremely prolific. Many articles are available online that introduce the method, a few of which can be found at the end of this post.

My experience of note taking and knowledge management

Before 2018, my notes were all in written notebooks. They were archived, but seldom looked twice. Finding relevant information was particularly difficult. Since then, I use both a physical notebook and a directory of Markdown files in a GitHub repository to take notes. When I have ideas while away from computer, I will write them down and edit a Markdown file later. Otherwise, I will directly open a Markdown file. The files are organized by dates, and they are listed as individual sections in the Markdown file.

I found the combination works well. And I organize the Markdown files in a static website so that I can even view them in a web browser, which is a good-to-have feature that I did not use much.

What is new about the Zettelkasten, compared with what I have had, is two fold: (1) the Zettelkasten system requires that notes must be linked, because unlinked notes will be lost, and (2) the notes are not organized by dates, but they are taken in a atomic and autonomous way, namely each note contains one and only one idea. Nevertheless, I keep a diary, i.e. a new Markdown file everyday, that links to ideas that I had or I learned on that day.

There are many ways to do this. I am using the simplest tools that I know: Markdown, the vim editor, the vimwiki and vim-zettel plug-ins for vim, and a GitHub repository. That’s it.

So far I feel intrigued about the Zettelkasten system, though due to the short time of using it, I cannot tell how beneficial it can be in the long run. I am cautiously positive, because the habit of taking notes in the last two years already helped me in one or another situation re-visit some old ideas and connect apparently distant ideas. I am glad to share what I learn in a future post.

Zettelkasten as a learning tool

Many people who used Zettelkasten reported positive experience, especially with regard to learning (survivor bias though may apply as well). I consider learning things as a process of acquiring the ability to explaining them to others, where others can be either humans, in which case the explanation is done by language and gestures, or computers, in which case the explanation is done by programming languages and workflows (here I am influenced by Donald Knuth). Taking notes of ideas of either people or of our own, especially in our own language, is not only a tool to pin vague ideas down, but also an attempt to explain them to ourselves.

If I use my own language instead of copy/paste when taking the notes, and have a learner as a virtual reader in mind, the process even simulates a teaching experience where I try to explain an idea to someone who is new to it. It can be seen as an implementation of the Feynman’s Technique, which proposes that a good way to learn a topic is to (pretend to) teach it to a kid in the elementary school, identify things that you cannot explain well, understand them better with the help of textbooks and other resources, and finally review and simply the message.

I like to image this process of acquiring knowledge and conveying key messages to other people or machines as ‘the metabolism of knowledge’. It is also used by popular tips about learning, for instance the drilldown method proposed by Scott Young, who proposes a three-step process of learning: first a wide coverage of the topic, then dedicated practice with feedback and proper granularity, and finally distilling insights, for instance with the Feynman’s Technique.

No matter what the name is, the key insight is that we cannot only only collect knowledge, because otherwise we fall into the collector’s fallacy, the tendency of collecting things and feeling good about the mere action of action, though even without benefiting from the collections (more about this in this post in Taking notes in our own languages and link them help absorb the knowledge instead of hoarding them.

Zettelkasten for resonance in an accelerating world

Beyond the apparent benefit for learning, I consider note taking and knowledge digestion as a way to resonate with both people and ideas in an accelerating world. I was inspired to take this view by reading the book Beschleunigung – Die Veränderung der Zeitstrukturen in der Moderne (Alienation and Acceleration: Towards a Critical Theory of Late-modern Temporality) by Hartmut Rosa, a sociologist, and his another book Resonanz - Eine Soziologie der Weltbeziehung. His theories and arguments left a strong impression on how I see myself and the world develop.

The key insights I gained by reading both books is that acceleration, let it be technological, social, and of our own life, has become an end in itself. Individual efforts to resist acceleration will largely fail, since it is the imperative of the system that we handle faster and accelerate processes whenever it is possible. To live a good life in such a society, besides pushing for changes on the system level, we need to take conscious decisions to resonate with ourself and with the world. I see a parallel thread between the resonance theory of Hartmut Rosa and the concept of Das Passende Leben proposed by Remo Largo, a Swiss pediatrician and scientist.


The idea of Discovery Weekly was born during the corona pandemic. It helped me collect and share what I see and learn every week. It helped me find writing as a way of thinking. I am honoured that many colleagues and friends read the Discovery Weekly series in the last three months, and offered both feedback and criticism, which are immensely valuable to me.

Now, with the new goal of metabolizing and linking knowledge, instead of merely collecting them, the Discovery Weekly will hopefully be transformed, in the time domain, into writings with more insights and depth. Thanks to the discovery of the Zettelkasten system, I think I have found a promising road to achieve the goal. What left is hard work and persistence. May the curiosity and courage be with me.

Have a nice weekend!

Resources about Zettelkasten: