Your brain is for having ideas, not storing them
David Allen wrote this in Getting Things Done, and it changed how I think about capture. Your mind is brilliant at generating ideas. It's terrible at holding them. Every open loop (that email you need to send, the article idea, the thing you promised your wife) takes up mental bandwidth. The more loops, the more background noise.
I notice this most when my head feels full. That restless, slightly anxious state where you know there's something you're forgetting but you can't put your finger on it. When I get that feeling now, I stop what I'm doing and do a brain dump. I open a note and write down everything that's floating around in my head. Work stuff, personal stuff, half-formed ideas, errands, all of it. No filtering, no organising. Just getting it out.
The relief is immediate. It's like unclenching a fist you didn't realise was closed.
How I actually capture things
My main capture tool is voice. I use MacWhisper to transcribe voice notes, then process them in Claude. Walking to the office, driving, after a meeting: I'll record a quick voice note with whatever's on my mind. The transcription isn't perfect, but it's good enough. The point isn't elegance. The point is speed.
For meetings, I capture actions in real time. Not full minutes, just the commitments: who said they'd do what, and by when. I started doing this after noticing that the people I admire in meetings always follow up within hours. They send a short message: "Here's what we agreed." It takes two minutes and it builds enormous trust. I wanted to be that person. So I started capturing during the meeting instead of relying on memory afterward.
Sometimes the idea is bigger than a quick voice note. That's when I sit down and do a proper brain dump: 15 minutes, everything out of my head, then sort it into what needs action and what's just noise. Most of it is noise. But the three or four things that aren't? Those are the ones that would have kept me up at night if I hadn't written them down.