I like the idea of a second brain. I use one, or at least some version of one. I save articles I want to return to, keep notes from things I read, collect references for projects, write down half-formed ideas, and try to put things somewhere I’ll be able to find them later.
There are plenty of systems for doing this, and I’ve borrowed from more than one of them. The names and methods differ, but the basic promise is compelling: your brain doesn’t have to hold everything. Put things somewhere reliable, organize them well enough, and retrieve them when you need them.
That still makes sense to me. And AI is making it much easier.
A few years ago, adding something useful to a knowledge system usually required a fair amount of manual work. You had to read it, decide what mattered, write a note, choose some tags, and figure out where it belonged. Now much of that can happen with very little help from me.
AI can summarize a long article, extract the main ideas, suggest categories, compare a new note with older ones, and point out connections I might have missed. It can process more material in minutes than I could reasonably get through in an afternoon.
I don’t think this is a bad thing. Some of that work was never particularly meaningful. I’m happy to spend less time copying passages, renaming files, or deciding which folder should contain what. If a machine can handle the maintenance while leaving me more time to do something useful, great.
In that sense, the second brain is getting better. Mine can hold more, search more, organize more. Increasingly, it can even make sense of what it holds.
And yet, at some point, I started feeling strangely uneasy about it.
Not overwhelmed, exactly. More like suspicious.
I would look at a growing collection of notes, summaries, saved articles, highlights, and links and realize that instead of feeling reassured by everything I had accumulated, I felt a little uncomfortable. There was so much good material in there. But how much of it was actually mine?
Not in the sense of ownership. In the sense of knowledge.
If I saved an article but barely read it, then kept a perfectly good AI summary of it, do I know what that article says? If an AI notices a connection between two notes that I never would have thought to put together, is that connection part of my thinking yet? If hundreds of notes have been categorized neatly without me having to decide where they belong, what exactly have I learned from having them?
These aren’t rhetorical questions. I’m still not sure where the line is.
We have always stored knowledge outside our heads. Books do it. Libraries do it. Notebooks do it. Search engines do it. There is nothing new, or particularly alarming, about relying on things outside our memory. The point of a second brain was never to memorize everything inside it.
But I think I had started quietly confusing a few different things.
Saving something is not the same as understanding it. Being able to retrieve something is not the same as knowing it. And having a well-organized collection of other people’s ideas is not necessarily the same as having more ideas of your own.
AI makes that distinction harder to ignore because my second brain can now grow much faster than my first brain can keep up. It can ingest faster than I can read. It can summarize faster than I can reflect. It can generate connections faster than I can decide whether those connections matter.
That is an extraordinary capability. But it also raises a different question about what a knowledge system is supposed to do.
Maybe the goal shouldn’t be to make the second brain as large, complete, and intelligent as possible. Maybe the better question is what all of that information does when it comes back to me.
Does it help me notice something I hadn’t noticed before? Does it leave me with a better question? Does it change my mind? Can I connect it to something I already know? Can I explain the idea without reopening the note? Can I turn it into a decision, an argument, a piece of writing, or a new direction?
Those seem like very different measures of a system. And as AI gets better at collecting, sorting, retrieving, and summarizing information, I suspect they will matter more.
That doesn’t mean I’m going to stop using AI. It doesn’t mean I’m deleting my notes.
I’m still going to save useful things. I’m still going to let AI summarize documents when that saves me time. I’m still interested in better search, better organization, and better ways to connect information.
I just want to be more careful about what all of that is for.
A second brain should reduce the burden on the first one. But reducing the burden shouldn’t mean removing it from the process. The system should eventually give something back: a question, a judgment, a connection that means something to me, a thought I didn’t have before.
For a long time, I was interested in how to build a better second brain. Lately, I’ve become much more interested in what would make the first one better.
I don’t want to get rid of my second brain.
I want my first one back.
The author is not a native English speaker. This post was translated into English with the assistance of AI.