The Compounding Second Brain

Your ideas don't die.
They connect.
They compound.

Memex turns everything you consume into a living map of your mind. It surfaces the threads, remembers what matters, and compounds your thinking over time.

01 · The Problem

You consume constantly.
Almost none of it sticks.

The average knowledge worker reads 5 articles a day, listens to 3 hours of podcasts a week, watches countless YouTube videos, saves hundreds of highlights. And then remembers almost none of it.

It's not a memory problem. It's a connection problem. Your brain builds understanding through associations — when a new idea links to something you already know, it becomes real knowledge instead of a fading impression.

But your tools treat every piece of content as an island. Readwise saves highlights in a flat list. Notion is a graveyard of half-finished notes. Pocket has 847 unread articles. Nothing watches across time. Nothing connects the dots.

The result: you're on a treadmill of consumption that feels productive but generates almost zero compounding intellectual value. That ends with Memex.

A typical week's intake — fate unknown
🎧
Lex Fridman · Sam Altman Episode
3h 12min · listened 80% · Mon
forgotten
📄
"Why Founders Fail at Scaling" — a16z
12 min read · 3 highlights · Tue
orphaned
📺
Naval · How to Get Rich (full)
2h 10min · watched fully · Wed
fading
📄
The Compounding Effect of Reading — FS
8 min read · bookmarked · Thu
never opened
🎧
Tim Ferriss · Adam Grant Interview
1h 45min · partial · Fri
orphaned
Memex: All five connect to one thread
"Non-linear returns on deliberate learning"
surfaced
02 · Who it's for

Built for people who
think for a living.

Three very different workflows. One compounding second brain.

AI Founders

You follow @karpathy, @sama, @ylecun on X. You skim r/MachineLearning and r/LocalLLaMA every morning. You read every a16z AI piece and every YC batch announcement. In January, Karpathy tweeted about inference-time compute. In February, a Reddit thread broke down why it changes model economics. In March, a16z published a full thesis. In April, five YC S25 companies shipped directly into this space.

You read all of it. You never saw it as one story. Memex did - and told you four months ago.

Thread · Inference-time compute
5 sources
X @karpathy · Jan 14
"Scaling inference compute at test-time is the next unlock..."
Reddit · r/LocalLLaMA · Feb 3
"Why inference cost curves matter more than training now"
a16z · Mar 18
"The case for inference-time scaling - full thesis"
YC S25 batch announcements · Apr 2
5 companies building directly on inference-time compute
✦ Memex synthesis
$140M in seed funding now validates the thesis you've been tracking since January.
4 months · 5 sources · market confirmed
Researchers

You have ArXiv alerts for three topics, ACL Anthology bookmarks going back two years, and a Semantic Scholar reading list you haven't opened since October. Last Tuesday a new paper dropped on predictive coding. It directly built on a Friston preprint you annotated fourteen months ago - and quietly contradicted a Clark finding you'd flagged as uncertain.

You would have cited them as agreeing. Memex caught the conflict before you wrote a word.

Thread · Predictive coding models
23 papers
ArXiv preprint · Friston et al. · Oct 2023
"Active inference under the free energy principle" - annotated
ACL Anthology · Clark & Manning · 2024
"Hierarchical prediction in language models" - flagged as uncertain
Nature Neuroscience · Dec 17 · new paper
"Revisiting predictive coding: a unified account"
Conflict detected
Nature (Dec) builds on Friston but contradicts Clark. Your belief on this is contested.
2 sources in conflict · review before citing
Investors

You built your TSMC position reading Bloomberg Terminal reports, two Stratechery deep-dives, an Odd Lots podcast on semiconductor geopolitics, and a chip analyst thread on X. That was eight months ago. Last week a Taiwan Strait headline moved your position 12%.

Memex had the full thread intact: six assumptions, sources for each, and two already under pressure before the headline hit.

Thread · TSMC investment thesis
6 assumptions
Bloomberg Terminal · Apr 2024
"TSMC's 3nm yield rate reaches production threshold"
Stratechery · Ben Thompson · Jun
"The geopolitics of semiconductor supply chains"
Odd Lots · Bloomberg podcast · Jul 8
"Taiwan risk premium in chip stocks is deeply underpriced"
2 of 6 assumptions under pressure
Taiwan Strait tension headline · Today - geopolitical stability + supply continuity now contested.
review thesis · position moved -12%
✦ Memex synthesis
Your original thesis and all six sources are intact. Here's what's changed.
03 · Features

Everything a second brain
should actually do.

🧵

Thread Detection

Automatically identifies recurring themes across all your content — even when the words are completely different — and surfaces them as living threads you can explore and annotate.

Contradiction Alerts

When a new idea meaningfully contradicts something you've previously bookmarked or believed, Memex flags it immediately. Cognitive dissonance is where real thinking happens.

📬

The Sunday Letter

Every week, Memex writes you a personal letter — what your mind consumed, what threads are emerging, what beliefs are crystallizing. A mirror of your intellectual week.

🎙️

Voice Captures

Had a thought in the shower? Record 30 seconds on your phone. Memex transcribes, indexes, and connects it to your existing threads — your spoken ideas are first-class citizens.

📊

Belief Graph

A visual map of your intellectual landscape — which ideas are well-supported, which are lonely hypotheses, which are battle-tested by dozens of sources. See your mind from the outside.

💬

Ask Your Archive

"What do I actually think about remote work?" Memex searches not just for saved quotes, but for your evolving stance — synthesizing across every source you've consumed on the topic.

04 · Insight Types

Four kinds of insight
Memex surfaces for you.

01
Convergence

Multiple sources, one truth

"You've encountered 'deliberate practice' in 8 different sources over 6 months — from Ericsson's research to a Tim Ferriss podcast to a YC essay. This is a well-supported belief now."

When enough independent sources converge on an idea, Memex promotes it from "interesting thing I read" to a genuine conviction in your belief graph.

02
Contradiction

Your assumptions, challenged

"In January you saved an article arguing founders should specialize early. This podcast argues the opposite with equal rigor. Your belief is now actively contested."

Memex surfaces intellectual tension before you forget one of the sources. These are the moments worth resolving.

03
Obsession Detection

What your mind keeps returning to

"You've consumed 14 pieces touching on 'decision-making under uncertainty' in 3 months. You haven't written anything about it. Is there something here you're trying to figure out?"

What you repeatedly seek out reveals what you're actually trying to solve. Memex names the unnamed questions driving your consumption.

04
Connection Across Time

Past you, meet present you

"A note you wrote 8 months ago: 'I don't understand why great teams fall apart.' You've now consumed 11 sources that together probably answer this."

Your old unanswered questions deserve answers. Memex tracks what you were puzzled about and tells you when you've finally gathered enough to understand it.

05 · Pricing

Built for thinkers.
Priced for individuals.

Curious
Free
Forever · no credit card
  • 50 pieces of content / month
  • Thread detection (up to 5 threads)
  • 7-day connection window
  • Browser extension
  • Basic weekly digest
Scholar
$45
per month · researchers & writers
  • Everything in Thinker
  • Collaborative threads
  • Export to Obsidian / Notion / Roam
  • Citation graph for academic work
  • API access
  • Priority synthesis