Your Brain Wasn't Built to Remember Everything

Your working memory holds about 4 items at a time. Not 7, as the old research claimed—more recent studies put the number closer to 4, plus or minus 1.

Four items. That's what you have to work with at any given moment.

Meanwhile, you're generating ideas, fielding requests, noticing things you want to remember, tracking tasks across multiple projects. The inflow vastly exceeds the buffer. Something has to give.

Most note-taking apps respond to this problem by promising perfect retention. Capture everything! Tag it! Link it! Build a second brain that never forgets!

Gravity takes a different approach: let things go.

By the end of this post, you'll understand:

• Why capturing thoughts is about freeing working memory, not building an archive
• How "sinking" turns forgetting into a feature
• The cognitive mechanism that makes review-and-rescue work

The working memory tax

Every uncaptured thought occupies mental real estate.

You're in a meeting, and you think of something you need to do later. Now part of your attention is tracking that todo while also trying to follow the conversation. You think of a second thing. Now you're juggling two background processes. By the time the meeting ends, your working memory is fragmented across a dozen half-held items.

This is the actual cost of not capturing: not that you'll forget (though you might), but that you're spending cognitive resources on remembering instead of thinking.

Karpathy describes the payoff of his note system: "When I note something down, I feel that I can immediately move on, wipe my working memory, and focus fully on something else."

That's the value of capture. Not retrieval later—relief now. Getting the thought out of your head so your head can do other things.

Why retrieval isn't the goal

Here's the uncomfortable truth about notes: most of them are never retrieved.

Think about the last 100 things you wrote down. How many did you actively search for later? If you're like most people, it's somewhere between 5-15%. The vast majority of notes serve their purpose at the moment of capture—offloading from working memory—and are never consciously accessed again.

This isn't a failure. It's the system working correctly.

The problem is when note-taking apps are designed around retrieval. They assume every note needs to be findable, so they add folders, tags, search, links. Each feature adds friction at capture time—the one moment when speed actually matters.

Gravity inverts the priority. Capture is instant and frictionless. Retrieval is... optional. Most notes won't be retrieved. That's fine. They still served their purpose.

The sinking mechanic

Here's what happens to a note in Gravity:

1. You capture it. It appears at the top of your stream.
2. Time passes. New notes get added above it. It drifts down.
3. You review your stream. You scroll, you skim.
4. If the note catches your attention, you rescue it—swipe right, it jumps back to the top.
5. If it doesn't catch your attention, it keeps sinking.
6. Eventually, old notes drift far enough down that you rarely see them.

No note is deleted. Nothing is lost. But attention determines prominence. The notes you keep rescuing stay visible. The notes you never rescue fade into the depths.

This is forgetting with a safety net. The note exists if you need it—you can search, you can scroll deep. But if you don't actively maintain it, it gracefully recedes.

What's actually happening in your brain

Let's get specific about the cognitive mechanism here.

When you encounter information repeatedly, neural pathways strengthen. This is the basis of learning—repetition consolidates memory. Spaced repetition systems exploit this: they show you flashcards at increasing intervals to maximize retention.

Gravity does something subtler. It doesn't force repetition. It creates opportunities for repetition and lets your attention decide.

During review, you're essentially running an attention filter across your notes. Some notes get noticed, retrieved into working memory, and reinforced. The neural pathways for those thoughts get stronger.

Other notes don't get noticed. They receive no reinforcement. The pathways weaken over time—not through active deletion, but through the natural decay that happens to unmaintained connections.

This is how your brain handles the forgetting problem in the real world. Gravity just makes the process visible and volitional. You're not fighting your brain's natural filtering—you're harnessing it.

Hold up—what about things I need to remember but don't find interesting?

Valid concern. Some notes are important but not engaging—reference information, administrative details, things you need but don't enjoy thinking about.

Two responses:

First, if something is truly important, external context will surface it. You need the login credentials when you need to log in. You need the meeting notes when the meeting follow-up happens. Importance often comes with triggers that prompt retrieval.

Second, prefixes help here. Tag the note with ref: or admin: and you can search for those categories directly when you need them. The note sinks out of your daily review—it's not occupying attention when it's not relevant—but it's findable when you actually need it.

The stream isn't meant to be your archive of everything. It's meant to be your working surface for what's alive right now.

The relief of letting go

There's a psychological weight to holding onto everything.

If every note is precious, every note demands attention. The backlog grows. The unread list expands. You carry the cognitive burden of all this unprocessed material.

Gravity's sinking mechanic is permission to let go.

Not every idea deserves follow-through. Not every article deserves reading. Not every half-thought deserves development. Some things were interesting in the moment and don't need to persist.

When a note sinks and you don't rescue it, you're not failing. You're correctly identifying that this thought, right now, isn't serving you. The note is still there if circumstances change. But you're not obligated to maintain it.

This is surprisingly freeing. The stream becomes a working surface, not a graveyard of unfulfilled intentions.

Why this compounds

Over time, two things happen:

Your stream becomes curated by attention. The notes at the top are there because you've repeatedly found them interesting enough to rescue. They've survived multiple rounds of filtering. The stream reflects what's genuinely alive for you.

Your capture becomes more calibrated. You internalize what tends to survive review and what tends to sink. You start filtering earlier—not capturing things that you know won't catch your attention later. Your throughput becomes higher-signal because you've trained your intuition on thousands of rescue decisions.

The system isn't static. It learns with you.

The permission to forget

Note-taking apps have convinced us that forgetting is failure. That we need perfect capture, perfect organization, perfect retrieval.

But your brain doesn't work that way. It's constantly filtering, constantly letting go of what's not reinforced. Fighting this is exhausting and ultimately futile.

Gravity works with your brain instead of against it. Capture quickly. Review regularly. Let your attention decide what matters. Let the rest sink.

The notes you forget were meant to be forgotten.

---

Capture instantly. Review naturally. Let go gracefully.