For grown-ups
PremiseBench is for ages 15 to 18. It opens four well-known models as editable diagrams: a city that grows and ages (after Forrester's Urban Dynamics, 1969), neighbours who move when too few nearby are like them (after Schelling, 1971), a shared pasture with and without community rules (after Hardin and Ostrom), and an outbreak (the SIR model). Every premise carries a bar for how sure anyone is of it.
The task is always the same: change one premise, run the model again, and write a one-page model card. What is in the model? What is left out? Who would disagree with it? What evidence would change your mind? The card is printed or kept on this device; nothing is sent anywhere.
The models here are deliberately small, and the page says what each leaves out. They are arguments, not forecasts. A good conversation is about one claim that often comes up in policy debates: that helping will backfire. Ask your teen when the model shows that, and when it does not.
What it never does
- No accounts, no ads, no tracking — anything kept stays on this device.
- No streaks, timers to beat, points to chase or leaderboards.
- No chat, and nothing anyone types is sent anywhere.
We describe what PremiseBench is designed to practise. We do not claim it raises test scores.
🧮 Back to PremiseBench
📜 Where this idea comes from· Kermack–McKendrick 1927 · Forrester 1969 · Schelling 1971
Who first built these models
In 1927 William Kermack and Anderson McKendrick wrote the equations for how a disease spreads through people who are susceptible, infected and recovered. In 1969 Jay Forrester modelled a whole city as stocks and flows in Urban Dynamics. In 1971 Thomas Schelling showed with coins on a grid that people who only mildly prefer neighbours like themselves can still end up in sharply divided neighbourhoods.
One thing to hold: A model card with four questions: what went in · what was left out · who disagrees · what evidence would change your mind.
Why it matters: Every model leaves things out on purpose. Naming what it leaves out is what makes a model honest.
Dates:
- 1927 Kermack and McKendrick, the epidemic model
- 1969 Forrester, Urban Dynamics
- 1971 Schelling, the segregation model
Sources: W. O. Kermack & A. G. McKendrick, Proceedings of the Royal Society A 115 (1927) · Jay W. Forrester, Urban Dynamics (1969) · Thomas C. Schelling, "Dynamic Models of Segregation", Journal of Mathematical Sociology (1971)