Photo by Alex Loup

What is a Zero Sum Game?

A quick intro to a very useful mental model

Julia Clavien
Nov 5, 2019 · 2 min read

If you don’t already know this mental 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.

🧠 Internalizing the model

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?

It’s worth being aware that we have a tendency to be somewhat biased in our assessment! So 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 (and math heavier) deeper dive into game theory if you’re keen!

🎥 Or if you want a lightweight way to learn a little more about game theory you must watch the magnificent movie — A Beautiful Mind.

📧 Like learning mental models? Check out the newsletter here.

Julia Clavien

Written by

Curious to a fault. Technology | Psychology | Philosophy. All opinion subject to change. ☺

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