Sciencespeaking topic
A human can only truly maintain close relationships with about 150 people; our brains can't handle more. While we live in cities of millions, are we still designed for a small tribe?
— Dunbar's number
practice with this topic
Set the timer (5-30 min), take 20 seconds of prep if you like, start talking. Jot your thoughts onto the sticky-note board.
similar topics
- Any two people in the world are connected on average by a chain of about six acquaintances. A fisherman in the Amazon and a banker in Tokyo are six handshakes apart. With billions of people so scattered, how does the world stay so 'small'?
- Paradigm shift: Kuhn argued that science advances not by steady accumulation but by rupture. Is a scientific revolution really possible without the old generation passing?
- Phantom limbs and the brain map: Ramachandran showed that phantom pain arises when neighboring regions take over the brain map of a lost arm. If our body is a map in the brain, can that map live on apart from the body?
- When an ant gets lost it leaves a trail to find its way back, but when trails overlap the colony sometimes marches in an endless circle until it dies. How does a seemingly flawless system commit suicide through its own rules?
- 'Sugar makes children hyperactive' has been scientifically debunked: blind studies found no difference, and the effect lives in the parents' expectation. Do we see it because we believe it?