If you don’t already know this week’s model, you may well have heard of it before. It’s a key concept from game theory to add to your growing mental set of models! 🧠

**What is a Zero-Sum Game?**

A situation in which one person or group can win something only by causing another person or group to lose it.

Often to explain zero-sum games a pie is discussed. Let's imagine it in the literal sense - we're both hungry and we get a pie to share. If I go ahead and scarf down most of it and only leave you a few crumbs and you're left hungry, we've just experience a zero-sum game. For one person (or side) to win, another must lose. It's a win-lose situation.

**What about Non-Zero-Sum Game?**

In contrast, *non-zero-sum games* (sometimes called *positive-sum games*) can be win-win situations. These are the type of situations that make the figurative pie bigger. International trade is a commonly used example - both countries can benefit via import and export of goods.

I wonder if Aristotle was thinking about a non-zero-sum game when he wrote:

The whole is greater than the sum of its parts.

## Why is this interesting?

**Can you notice anything in your life that's a zero-sum game?**

What about non-zero-sum games? Maybe from personal relationships or high performance work teams?

We have a tendency to be somewhat biased in our assessment!

Watch out for **Zero-Sum Thinking:**

A general belief system about the antagonistic nature of social relations, [...] based on the implicit assumption that a finite amount of goods exists in the world, in which one person’s winning makes others the losers, and vice versa [...]

a relatively permanent and general conviction that social relations are like a zero-sum game. People who share this conviction believe that success, especially economic success, is possible only at the expense of other people’s failures.

**Want to go deeper?**

📙 Here's an interactive (math heavier) deeper dive into game theory if you're keen!

🎥 Want a more fun way to learn a little more about game theory? Watch the magnificent movie - A Beautiful Mind.

I’m loving hearing your thoughts and reflections on the models, by both email 📧 - just hit reply - and via twitter - 🐦@juliaclavien!

Wishing you a week of growing the pie dear Mental Modelers! 🙇