One scope per brain
Each brain covers one role or domain, and only that. When you switch roles, you switch brains. Mixing them is how a board paper ends up next to the school run, and neither gets found.
The cost of changing lines
Every switch has a toll. You walk out of one meeting and into another, and for the first few minutes you are catching up: who said what last time, what you promised, what this person actually cares about. Sometimes you never fully catch up, and the meeting runs on half the context it deserved.
Good switching feels different. You sit down and the line is already connected. Last decisions, open questions, the document you meant to reread. Everything from your other roles has gone quiet, not deleted, just not on this call.
Not more knowledge. Less friction between the roles you already have.
What went wrong four or five times
I have built a second brain four or five times. Each started the same way. I saved meeting notes, articles, ideas, half-finished thoughts, anything that might matter later. Before long the system knew a lot and helped with very little.
That is the trap. Saving is easy and feels productive. Finding the one useful thing among a thousand saved ones is not, so you stop looking, and then you stop saving. What you are left with is a data lake with no fish in it.
What changed was deciding what not to keep. Each brain now has one job and a narrow scope. Memory is chosen, not collected. And curation is a habit at the end of a session, not a clean-up project I promise myself for next month.
NoiseFull meeting transcript, 14,203 words
KeepPricing decision still open
DuplicateCalendar event, copied again
NoiseAn article saved without a reason
KeepSend revised proposal by Friday
NoiseRoutine status update, now obsolete
DuplicateDocument another system owns
KeepThe question the board left open
Move the control from collection to selection.
The recipe
There is nothing magic in it. It is four rules, and the value comes from keeping all four. Drop one and the data lake starts filling again.
Selected memory
Keep decisions, commitments, preferences and the few facts you will need again. Leave out transcripts, routine noise and anything another system already owns.
A regular wrap
At the end of a session, spend a few minutes deciding what is worth keeping and correcting what has changed. Small and often beats a big tidy-up you never get round to.
A front end that moves first
Most systems wait to be asked. Built properly, this one does some work first. Before you open a context line, it has read what changed, pulled the papers for the next meeting and drafted the obvious follow-up. You sit down to a prepared desk, not an empty search box.
What it might look like for a CEO
My own brains are split by role. A CEO's would be split by what their life actually contains, and for some that might be three lines: the company, the boards they sit on, and private life.
CompanyStrategy, the leadership team, open decisions and what was promised to whom.
BoardsEach board kept separate, with its own papers, people and confidentiality.
PrivateFamily, friends and the commitments that tend to lose out to the calendar.
Those three are an example, not a template. Someone else might need an investor line, or a split between two companies. The rule is the same: one line open at a time, and the brain gets you there quickly. The judgement stays with you.
What it has done before you sit down
Showing you the next meeting is the floor. With the right access and some clear rules, the system can work ahead of you: preparing, noticing, drafting and nudging things along, so the line you open next is already moving.
PreparesMeeting briefs with history, open points and papers
NoticesChanges, silences and loops nobody has closed
DraftsFollow-ups, replies and first versions of material
AdvancesRoutine work, within rules you have set
Before a board meeting it can pull the last minutes, the actions still open and what has changed since, and put them on one page. It can suggest the thing you would have remembered on Thursday, too late: call this person, reread that clause, move this to next week. It can flag signals: a number drifting, a thread gone quiet, a promise with no owner. It can draft the follow-up while the meeting is still fresh. And it can push routine work forward on its own, within rules you have written.
What it should not do is decide anything that matters. It prepares the decision. You make it.
What you get
Faster switchingYou arrive in the next role already briefed, instead of spending the first part of the meeting working out where you left off.
Less lost between rolesCommitments, decisions and open questions survive the switch, so less falls through the gap between one context and the next.
Better interactionsBetter meetings and conversations. You arrive with a brief you did not have to ask for: what was promised last time, what has moved since, a draft of the follow-up. The other person notices.