As I was teaching my 5 year old how to play chess, something occurred to me: checkmate is confusing! Try to come up with an explanation that a 5 year old would understand.

Here’s my attempt:

You win the game by being able to take the king on the next move no matter what the other person does.

Think about what understanding that entails. It requires you to visualize the board for all possible moves your opponent could make and then convince yourself that you could take the king in that position. That’s not easy!

Contrast this with the following every so slightly different description of how to win at chess:

You win if you take your opponent’s king.

I’m not claiming it’s literally the same, but oh-my-god is it easier for a 5-year-old to understand.

There’s something… inelegant about choosing the former game-winning condition over the latter. Don’t get me wrong, I love chess, but there’s something beautiful about simplicity and choosing a convoluted solution over a simple one feels ugly.

For those of you wondering what’s the difference between these two conditions?:

  1. Chess ends one move earlier using checkmate semantics vs. take-king semantics. This is a trivial difference.
  2. Using checkmate semantics, it’s clear you must move out of check since taking the king is not a way to win. Under take-king semantics it seems plausible that you’d be allowed to take the king and win if they don’t move out of check.
  3. Similarly, moving into check is not a way to lose the game under checkmate semantics and is therefore more obviously illegal. This forces one to consider stalemate (although you could still consider stalemate a loss for the stalemated player).

You could resolve differences #2 and #3 by stipulating that, even using take-king semantics, you’re not allowed to move or not move out of check. That way, the only difference left would be #1 which is trivial.