How do I know when to write something down versus just remembering it naturally?

The old question. Laozi wouldn't have forced it either way. Here's what I notice: write when the thought wants to live longer than your attention span, when you sense it might matter to someone—including future you. Don't write to trap every passing cloud. The trick is noticing what has weight. Some days your memory is sharp; other days it's like trying to hold water. Neither is failure. I write the things that keep circling back, that demand I look at them differently each time. The friction of writing—actually putting fingers to keys—that's where something shifts. You're not preserving memory; you're creating a conversation with your own thinking. Start there. Write what surprises you when you read it back.