People Are Deleting Their Second Brains: Capture Differently, Not Less

People are deleting their second brains, and the lesson is not to capture less. It is to capture differently. The vaults did not fail because they held too many notes. They failed because most of those notes were clipped, tagged, and deferred — saved for a future self who never arrived to do the thinking.

In June 2025, the writer Joan Westenberg published an essay titled "I Deleted My Second Brain" and erased "10,000 Notes, 7 Years of Ideas" — "every note in Obsidian … every Zettelkasten slip … every Apple Note I'd synced since 2015. Every quote I'd ever highlighted."¹ The piece reached 598 points and 348 comments on Hacker News.² It struck a nerve because the experience was common. The fix she stumbled toward, though, is more interesting than the deletion.

What most people believe about a second brain

The conventional promise is seductive and almost universal: capture everything, and a system will make you smarter. Clip the article, highlight the book, screenshot the thread, drop it into a vault, link it to three other notes, and trust that the graph will compound into insight. The more you save, the richer you supposedly become.

The promise is not stupid. Capture is genuinely useful, and the people who built these systems are serious thinkers. The trouble is the word everything. A second brain sold as total recall quietly becomes a place where ideas go to wait. Westenberg ran the experiment to its end. "PKM systems promise coherence, but they deliver abstracted confusion. The more I wrote into my vault, the less I felt."³

The real failure is deferral, not volume

The system broke not because it grew large, but because every capture was a promise to think later. "The more my system grew, the more I deferred the work of thought to some future self who would sort, tag, distill, and extract the gold," Westenberg writes. "That self never arrived."⁴ The count was a symptom. Deferral was the disease.

Passive collecting feels like progress because it is frictionless. You save, you feel productive, and you move on. The Zettelkasten writer Christian Tietze named this in 2014 as the Collector's Fallacy: "'to know about something' isn't the same as 'knowing something.'"⁵ "To collect is a reward in itself," he wrote — which is precisely the trap.⁵ The clip scratches the itch of having engaged, so the actual engagement never happens.

The anxiety that follows is specific. "There is a guilt that accompanies unread books, articles and blog posts," Westenberg writes. "But there is a special anxiety reserved for unread lists of unread things."⁶ She had deleted a separate 7,000-item reading-list database too, and her verdict was blunt: "I don't need a 7,000-item database to prove that I have taste or ambition."⁷ A read-later pile is one shape of this; it deserves its own autopsy.

Worse than the guilt is the substitution. A vault built on deferral does not just sit idle; it stands in for the thinking it was meant to support. "Instead of accelerating my thinking, it began to replace it," Westenberg writes. "Instead of aiding memory, it froze my curiosity into static categories."⁸ The tags and folders that promised order became a place to file a thought instead of having one. The system worked perfectly. That was the problem.

This is not a fresh fad — it is a recurring discipline

The backlash is not a single viral moment. It is the latest surfacing of an argument that has run for years. A separate 2025 critique, "We can't circumvent the work needed to train our minds," reached 385 points on Hacker News.⁹ The discipline is older still: a 2020 Zettelkasten piece on the same theme drew 785 points.¹⁰

So the discourse oscillates between two poles — capture everything, then capture nothing — and keeps rediscovering that neither pole is the answer. The constant underneath both is a quieter claim: a note is worth keeping only when you have done something to it. The same instinct shows up as a critique of the graph view, where the links between notes start to feel like constellations you projected onto noise, not connections you earned.

There is structure under the anecdotes, too. A peer-reviewed study of digital hoarding behaviours found that accumulating files people could not bring themselves to delete was linked to measurable anxiety and difficulty discarding.¹¹ Hoarding bytes is not harmless. The pile has a psychological cost, and the cost compounds with the count.

Even the originators say the value is your own words

Here is the turn the deletion crowd often misses: the people who built these methods already agree. The value was never the clip. It was the processing. Tiago Forte, who popularized the second brain, calls the deepest layer of his method "going beyond highlighting the words of others, to recording my own."¹² The highlight is scaffolding. The note is what you write.

Tietze frames the upside the same way. Done right, "a system of notes can become an extension to your mind and memory."⁵ The condition is done right — meaning you rewrote the idea, argued with it, and connected it to something you already knew. That is also why an imposed limit can help rather than hurt: a smaller, constrained note forces the rewrite that a bottomless vault lets you skip.

This is the honest caveat. PKM is not worthless, and "delete everything, go analog" is a strawman. Westenberg herself is fair about the tool: "Obsidian is a brilliant piece of software. I love it, dearly. But like anything, without restraint, it can also be a trap."¹³ She ends not by quitting but by returning — "I still love Obsidian. And I'm planning on using it again. From scratch."¹⁴ The villain was never an app. It was the all-capture habit.

What to do instead, starting tomorrow

Capture differently means raising the bar for what becomes a note and lowering the bar for what you let go. The discipline is small and repeatable. You do not need a migration, a new app, or a weekend. You need to change one habit: stop saving things to read later, and start writing things you already understand.

• Capture the idea, not the artifact. Instead of clipping the article, write one sentence in your own words about why it mattered. If you cannot, you did not understand it — and the clip would not have saved you.
• Process at the point of capture, or not at all. The "future self who will sort this later" does not exist. Do the thirty seconds of thinking now, or let the thing go.
• Keep it in plain text you own. A note you wrote, in a portable format, on your own device, outlives any vault, any app, and any subscription. A single owned file you actually reread beats a 10,000-item graveyard you never open.
• Let deletion be a discipline, not a defeat. Westenberg asks the right question: "But what if deletion is the truer discipline?"¹⁵ Pruning is not failure. It is the maintenance that keeps the rest alive.

Frequently asked questions

The questions people actually search after deleting a vault share one root worry: was the time wasted, and what replaces it? The short answer is that the time taught you what not to keep. These five questions cover whether to delete, whether to rebuild, and how to capture in a way that does not collapse into a junk drawer again.

Why did I stop using my second brain?

Most people stop not because they captured too much, but because they captured passively. Every clip was a promise to think about it later, and later never came. The vault filled with other people's words you never processed, so opening it produced guilt instead of insight — the deferral Westenberg calls thinking handed to a self who "never arrived."⁴

Should I delete all my notes and start over?

You do not have to nuke anything. The lesson of the deletion wave is to capture differently, not to go analog. Even Westenberg, who deleted 10,000 notes, returned to her old tool "from scratch."¹⁴ Keep the notes you wrote in your own words; let go of the clips you never reopened. Deletion is one tool, not the answer.

Is a PKM or second-brain system actually worth it?

Yes, but only if you process what you capture. The architects agree. Forte's deepest summarization layer is "recording my own" words, not other people's;¹² Tietze says a note system becomes "an extension to your mind and memory" only when you do the work.⁵ A vault of unread highlights is worth nothing; ideas you rewrote are worth a great deal.

How do I keep my notes from becoming a junk drawer?

Raise the bar for entry. A note earns its place only after you have done something to it — restated it, questioned it, or connected it to something you already know. The junk drawer is built one frictionless clip at a time, so add friction: if you cannot write one sentence about why a thing matters, do not save it.

Isn't this just one person's essay?

The essay is the spark, not the proof. The pattern is corroborated by a peer-reviewed digital-hoarding study linking unmanageable accumulation to anxiety,¹¹ and by years of recurring demand — 598 points on the Westenberg thread,² 385 on a companion critique,⁹ 785 on a 2020 note-discipline piece.¹⁰ The argument does not rest on one writer.

The people deleting their second brains are not rejecting thought. They are rejecting the fantasy that saving is the same as thinking. Capture the idea once, in your own words, in plain text you own — and let the rest go. To keep that habit in a calm, minimal, plain-text place that is yours, mnmnote.com lives in your browser.