Parable of the Polygons: Math Explains Segregation

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Parable of the Polygons

Here’s a fascinating, interactive post about triangles and squares. Spoiler alert: it’s not actually about just triangles and squares. It’s about us.

Vi Hart, known for her crazy math doodle videos, and Nicky Case, who makes public domain “playables,” created the Parable of the Polygons, based on Thomas Schelling’s 1971 paper Dynamic Models of Segregation. Using triangles and squares, the post demonstrates how small changes in attitudes can have big changes in the population—or, as Hart and Case put it more pointedly, “how harmless choices can make a harmful world.”

It’s an interesting idea to ponder. If everyone has a slight tendency toward living in neighborhoods (or sitting at lunch tables) where they’re not in the minority, then we naturally self-segregate. If we have a slight tendency toward living in diverse neighborhoods, then we begin to integrate. But if we’re already segregated, simply being okay with diversity isn’t quite enough—you actually have to prefer it.

The point that I found particularly illuminating: small individual biases lead to large collective biases. That can explain why we can feel like, hey, I’m not that biased (or sexist or racist or whatever)—I’m much less biased than society as a whole seems to be. But it turns out that our small leanings can get magnified and become the cultural norms.

Rather than just trying to restate the post, you should just head over and check it out.

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