This is a story of how harmless choices can make a harmful world.

These little cuties are 50% Triangles, 50% Squares, and 100% slightly shapist. But only slightly! In fact, every polygon prefers being in a diverse crowd:

You can only move them if they're unhappy with their immediate neighborhood. Once they're OK where they are, you can't move them until they're unhappy with their neighbors again. They've got one, simple rule:

“I wanna move if less than 1/3 of my neighbors are like me.”

Harmless, right? Every polygon would be happy with a mixed neighborhood. Surely their small bias can't affect the larger shape society that much? Well...

drag & drop unhappy polygons until nobody is unhappy:
(just move them to random empty spots. don't think too much about it.)

And... our shape society becomes super segregated. Daaaaang.

Sometimes a neighborhood just becomes square, and it's not their fault if no triangles wanna stick around. And a triangular neighborhood would welcome a square, but they can't help it if squares ain't interested.

In this next bit, unhappy shapes automatically move to random empty spots. There's also a graph that tracks how much segregation there is over time.

run this simulation a few times. what happens?

What's up with that? These are good shapes, nice shapes. And yet, though every individual only has a slight bias, the entire shape society cracks and splits.

Small individual bias can lead to large collective bias.

Equality is an unstable equilibrium. The smallest of bias can push a whole society past the tipping point. Well, what if we taught these shapes to have zero bias? (Or if you're feeling particularly nasty today, more bias?)

use the slider to adjust the shapes' individual bias:

Notice how much more segregated things become, when you increase the bias beyond 33%. What if the threshold was at 50%? Seems reasonable for a shape to prefer not being in the minority...

So yeah, just turn everyone's bias down to zero, right? Haha, NOPE. The real world doesn't start anew with a random shuffling of citizens every day. Everyday, you're not shuffling.

world starts segregated. what happens when you lower the bias?

See what doesn't happen? No change. No mixing back together. In a world where bias ever existed, being unbiased isn't enough! We're gonna need active measures. What if shapes wanted to seek out just a lil' more variety?

Woah. Even though each polygon would be okay with having up to 90% of their neighbors that are like them, they all mix together! Let's see this play out on a larger scale, when we change the amount of bias and anti-bias for all shapes.

world starts segregated. what happens when shapes demand even the smallest bit of diversity?

All it takes is a change in the perception of what an acceptable environment looks like. So, fellow shapes, remember it's not about triangles vs squares, it's about deciding what we want the world to look like, and settling for no less.

(hint: don't move them straight to the box; keep the pairs close together)

At first, going out on your own can be isolating... but by working together, step by step, we'll get there.

finally, a big ol' sandbox to play around in.

1. Small individual bias → Large collective bias.
When someone says a culture is shapist, they're not saying the individuals in it are shapist. They're not attacking you personally.

2. The past haunts the present.
Your bedroom floor doesn't stop being dirty just coz you stopped dropping food all over the carpet. Creating equality is like staying clean: it takes work. And it's always a work in progress.

3. Demand diversity near you.
If small biases created the mess we're in, small anti-biases might fix it. Look around you. Your friends, your colleagues, that conference you're attending. If you're all triangles, you're missing out on some amazing squares in your life - that's unfair to everyone. Reach out, beyond your immediate neighbors.

Thank you for playing this blog post!

Our cute segregation sim is based off the work of Nobel Prize-winning game theorist, Thomas Schelling. Specifically, his 1971 paper, Dynamic Models of Segregation. We built on top of this, and showed how a small demand for diversity can desegregate a neighborhood. In other words, we gave his model a happy ending.

Schelling's model gets the general gist of it, but of course, real life is more nuanced. You might enjoy looking at real-world data, such as W.A.V. Clark's 1991 paper, A Test of the Schelling Segregation Model.

There are other mathematical models of institutionalized bias out there! Male-Female Differences: A Computer Simulation shows how a small gender bias compounds as you move up the corporate ladder. The Petrie Multiplier shows why an attack on sexism in tech is not an attack on men.

Today's Big Moral Message™ is that demanding a bit of diversity in your spaces makes a huge difference overall. Look at Plz Diversify Your Panel, an initiative where overrepresented speakers pledge not to speak on panels without diverse representation.

Our "playable post" was inspired by Bret Victor's Explorable Explanations and Ian Bogost's procedural rhetoric.

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Thank you to our beta-readers:
Andrea, Astrid, Catherine, Chris, Emily, Glen, Jocelyn, Laura, Marc, Marko, Zak

Also Seen On:
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Things Based Off This Thing:
Polygons with Pentagons, Polygons in Snap!, Playthrough Video