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The Second Brain Company

The Second Brain Company

What we learn together should not disappear between conversations.

Every project adds to what a team knows. Yet much of it stays in someone's head, a passing conversation, or a place the next person cannot find. Work changes hands, and the learning starts over.

We believe knowledge should be a shared, durable part of work. People and the AI tools they use should be able to find it, question it, add to it, and carry it forward.

What we learn should accumulate.

A useful answer should become a starting point for the next question. Record what was learned while the context is fresh, so the next person can move forward instead of starting over.

Pass on the reasons, not just the result.

A decision without its reasoning is easy to misuse. Keep the why alongside the what: the assumptions, tradeoffs, and evidence that help someone decide whether it still holds.

Shared knowledge needs shared stewardship.

People should know who can use and change what the team knows. Changes should have a visible history. When something is wrong, the team should be able to correct it and understand how it got there.

AI should work from what the team knows.

An agent is more useful when it can find the team's knowledge, use it in context, and help put new learning back where everyone can find it. The conversation is a way in; the knowledge belongs to the team.

Your knowledge must remain yours.

Keep it in a form people can read and agents and tools can use. Keep its history. Be able to take it with you. A tool should help your knowledge grow, not become the only place it can live.

Our first product

Cortex

We are building Cortex to put these principles to work: a shared home for knowledge that your team and its AI tools can use, build on, and keep.

Meet Cortex