Glossary
Dunbar's number
Dunbar's number is the idea that humans can maintain about 150 stable relationships at once — a cognitive ceiling on your active network.
Proposed by anthropologist Robin Dunbar, Dunbar's number (~150) is the suggested limit on the number of people with whom one can maintain stable social relationships. It's organized in layers — roughly 5 intimate, 15 close, 50 good friends, 150 meaningful contacts, and looser layers beyond.
It's a cognitive ceiling, not a hard law: tools that extend your memory effectively raise how many relationships you can keep warm.
Why it matters
Once your network passes ~150, relationships start decaying silently — not because you stop caring, but because you can't hold everyone in your head. Knowing the ceiling is the case for an external system.
Wend is external memory for the layers past 150 — try the free Dunbar's number calculator to see where your network sits.