01 · The idea · 8 min
Second brain
A memory you can search, outside the one you take into the next case. Not a second chart. Not a pile of PDFs.
What I mean
A second brain is the notes you can find again. The memory you carry between cases does not keep the decision, the paper, or the bailout. The chart does not either. The chart is the record. This is the note you think with.
I built mine so a sentence captured after a case can become a procedure note, a talk, a paper, or a video a fellow can follow. The notes are plain text. They link to each other. One idea per note. The title is the question the note answers. If a note has two ideas, it is two notes.
Obsidian is only the window. The second brain is the notes, and the habit of using them. If you already have that habit in another tool, keep it. Do not switch for the look of an app.
Five moves
The same five, in order. Then stop reorganizing.
| Move | Do this | Not this |
|---|---|---|
| Capture | A sentence in the inbox, between cases | A finished teaching note, written tired |
| Process | File it in the right place, or delete it, within a week | A second inbox you never open |
| Connect | Link it to two other notes | Admiring the graph |
| Synthesize | A short map that collects one theme | Rereading forty notes to find the point |
| Output | A talk, a paper, or a video made from the notes | Moving folders around and calling it work |
I try to empty the inbox within a week, and I do a short review on Friday. The day does not matter. The emptying does. A map of content is just a note of links. It is how a theme stays findable without a folder named after the disease.
What I refused to build
- A folder for every disease. Folders are purposes: an inbox, a case, an operation, a project. A topic is a link or a tag.
- The graph as the system. The graph is a picture of links you already made. If you need the picture to find a note, the title is wrong.
- A second chart. Working notes are not the record. What those notes are allowed to contain is decided later, and your hospital decides it, not this page.
- An AI as the memory. A model can read the notes and draft from them. A chat log will not be there on Sunday. The note has to be.
- A dump of every PDF. A paper earns a note when it changed a decision. The file alone is not a thought.
Then the setup
- Obsidian, the window. Install, sync, and the few settings that matter.
- The vault. The folders I use, how notes link, and what I decided the vault may hold.
- The AIs. A written job the model has to read, and what may leave the machine.
- The video. The operative note, then the picture, then the words.
If you only have a weekend, the six checks on the start page are enough. This page is not a seventh checkbox. It is the reason the six exist.
Questions in this chapter
What is a second brain?
Short answer
The notes you can find again. Memory between cases does not keep the decision, the paper, or the bailout. The chart is the record. This is the note you think with.
- One idea per note. The title is the question it answers.
- Capture, process, connect, synthesize, output. Then stop reorganizing.
- The app is the window. The notes are the system.
How is this different from the chart, or from the notes I already keep?
Short answer
The chart is the record. A second brain is the working note: the decision, the bailout, and the paper that changed the choice, linked so you can find them.
- If you can already find that note in a minute, keep the tool you have.
- If it only exists in a slide or a chat, it is already gone.
- What the note is allowed to contain is a hospital decision. This page does not make it.