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Why I don't like Second Brain (PKM)
My problem with a second brain.


Read time: 6 minutes
Welcome back, 1600 readers, to the Learning Lab.
A weekly newsletter that helps you build your learning systems and become lifelong learners
đź§ Brain Warmup
(A question, riddle, or conundrum to mull over)
My voice is tender, my waist is slender and I'm often invited to play. Yet wherever I go I must take my bow or else I have nothing to say.
Congratulations to Clew Liwi and Celina Hellgermann, who was the only two to solve last week’s puzzle. 🥳
I have braches, but no leaves.
I have pages, but no words
I have spine but no bones.
I tell stories, but no voice.
What am I?
The answer was ”a book”.
Now back to the thread…

With about 1,570,000,000 search results in 0.78 seconds, the Second Brain is taking over the productivity space.
The Second Brain is a system designed to capture and organize information, also known as personal knowledge management system (PKM).
I won’t address Tiago Forte’s Second Brain methodology, but rather PKM in general.
This newsletter has 3 parts:
The basics of PKM
My problem with the PKM
The future of PKM
The basics of PKM
The PKM is an extension of your brain.
If your brain is a house. Your knowledge is your stuffs.
Then PKM is renting a warehouse. The popular “warehouses” are Evernote, Notion, Readwise, Roam Research…

A PKM aims to solve the following problems:
Unorganized information
Forgetting important information
Finding new connections when needed
You can read the summary about the summary here:
But does a second brain (PKM) actually works?
Let’s go on an investigation of each problem:
1. Unorganized information
Textbooks, videos present organized information, but in the wrong order for you.
Because, based on your prior knowledge, we need a different order to learn things.
Through questionings and thinking, you would find the right order.
As a general rule, your questions should promote:
Compare and contrast
Deep thinking and evaluation
Asking questions to find relationships
What are the core principles of organizing information?
Watch this video to learn the right order for learning:
2. Forgetting important information
You forget something if it’s:
Irrelevant
Disconnected
Not important to you
From these three principles, you can make your learning more memorable by:
Using different analogies
Thinking about the different relationships
Aiming to solve an important/personal problem
If you are familiar with my writing, one word probably popped up for you:
Encoding!
Encoding = connections form when you see the bigger picture but also zoom in to the tiny details.
The process of encoding itself will show you the relationships.
Here’s the process:
Questions → Relationships (new connections form) → Categorization (new connections form)

So, from all these principles, what is the perfect scenario for a PKM?
A great PKM works alongside your brain, not replace it.
It should help you:
Encode information better
Include basic retrieval practice for better memory
Question what you learned with a higher order of thinking
But in contrast, most PKM lacks these areas.
From my understanding, here is how people do it:
Capture idea → Add to inbox
Organize → Place in buckets or categories
Distill → simplify to the essence
Express → Regurgitate or create something new

This process leads to potential problems like:
Low-quality encoding = fewer meaningful connections = more forgetting
Valley of disappointment = You need lots of notes to find the “unexpected” connections.
Overreliance on tech = illusion of learning (no actual learning).

The Future:
The future of PKM will help manage your information, but it should never replace the process of learning. And it’s nearer than you think. Ahem… it’s AI.
I know that there are nuances of information that GPT doesn’t have, but soon there won’t be any barriers. We will have personalized ChatGPT assistant that memorizes all the important information and preferences.
Like Jarvis:

Ok, maybe not this cool. But you get the point 🤣When you need anything, just ask.
Nevertheless, PKM or AI should never replace your ability to think and do quality encoding.
Facilitate not replace.
Final remarks:
Most people who are using a PKM should focus on improving the quality of encoding. For the details hard to remember, throw it into a flashcard app or use a PKM for that.
Sorry that this newsletter is later than expected. 🥹
This was fun to rewrite. I hope you enjoyed reading it.
🧬 Life Update
I hope you enjoyed reading this post. I know I haven’t been active on X and I wish I had a better explanation then the fact that I am too busy with all my different projects and it’s taking the toll on my creative juice and brain power. X is not the same like when I started, nowadays, I feel so isolated, and it feels like all my friends have already left. Lately, I’ve been studying the book Meditation by Marcus Aurelius, so I just want to leave you with this beautiful quote I learned:
““Do not act as if you were going to live ten thousand years. Death hangs over you. While you live, while it is in your power, be good.” — Marcus Aurelius.“
Start living my lab partner, we are all here for a purpose!
⚠️ Disclaimer
I am not a learning coach (yet).
My techniques are mostly based on my experience and the research that I have done. Please be conscious while applying these methods.
