Why Chess Works
Discussion of the properties of Chess and related games.

Why Chess Works


When parents ask chess coaches why their children should study chess, the coach will often give an answer which might well be true of other games. Chess brings out discipline, patience, a fighting spirit, and other worthwhile traits, in anyone who puts in a certain amount of work into it.

But is this not like deciding on going out to eat at a steakhouse, as opposed to a fast food restaurant, on the grounds that there is food at the steakhouse. There's food at the other places too! That's why we need to decide. And one presumes that there are reasons for the decision of one over the other. 

Another reason often given is that chess games contain beautiful combinations. But this is rather like deciding between two movies at the cinema, and selecting movie A over movie B, on the grounds that movie A contains Hollywood actors, and both movies contain Hollywood actors. It is question begging, and it doesn't tell you why one, and not the other. There are many games like chess, which contain beautiful and deep combinations and ideas

There are more chess-like games than Western Chess. Chess, Shogi (Japanese Chess) and Xiangqi (Chinese Chess) share a common ancestor in Shatranj. These games could well be called Shatranj variants. (Shatranj itself derives from Chaturanga, an even older game. The rules for Shatranj are known, but the rules of Chaturanga are not.) Chess, Shogi, and Xiangqi have variants of their own. Some of these variants are popular, while others exist in a more abstract way, without a significant community of players.

In Shatranj, the pawns do not move two spaces at once. There is no therefore no en passant. There is also no castling rule. There is no Queen, but a Counselor, which moves one square diagonally. And instead of Bishops, there are Elephants, which jump two squares diagonally. A pawn which reaches the 8th rank promotes to a Counselor. Checkmate wins the game, but so does stalemate. A player who only has a King remaining also loses.

ChessV Software, Gregory Strong

Shatranj is a slower game than chess, and from the perspective of a chess player, a little frustrating. No elephant can capture any other, and the counselor often observes helplessly as it is restricted to half of the board. My few wins against the computer were arrived at by taking all of its pieces, since I could never find checkmate with such limited material. It is important to remember that games need human players to give them life, and my games with the computer on a slightly clunky software, combined with my lack of experience, no doubt made it harder for me to appreciate the depth of the game. However, Shatranj has always been adapted wherever it went. 

Why did people make these changes? One might explain the changes as purely cultural, or as arbitrary fashions. The various properties of the game, such as the size of the board, the movements of the pieces, and the conditions of victory and defeat, would all be roughly like our choices of attire. We might cringe a little at 80s hairstyles, but then young people in twenty years might cringe at the fashions of the 2020's, and there is no real truth of the matter. Probably this position is one most chess players will reject. There has to be something intrinsic to the game. Having played some Shatranj, I see the value of the two pawn move, castling, and especially of having two Bishops, which control all of the squares of a certain color. (However, Chinese Chess retains the two elephants, which are even more limited, because they are restricted to their own side of the board.)

In an interesting article, On Designing Good Chess Variants, Fergus Duniho says that Chess, Shogi, and Xiangqi have a lot going for them as games, and that anyone trying to invent a variant needs to understand what makes them work as games. His criteria is as follows:

  • Enjoyment: It should be enjoyable.
    • Excitement: How exciting it is to play.
    • Satisfaction: How satisfying it is to have won or to have played your best.
    • Duration: A short game is unsatisfying, and a long game is tedious.
    • Decisiveness: The likelihood that one of the players will enjoy victory.
  • Playability: How easy it is to learn and play.
    • Simplicity: How easy it is to learn, remember, and apply the rules.
    • Clarity: How easy it is to think ahead and foresee potential outcomes.
  • Interest: What the game offers to sustain long-term interest.
    • Depth: How much the game rewards serious study and analysis.
    • Challenge: How challenging the game remains for experienced players.
  • Fairness: The deciding factor in who wins should be skill, not who plays which side.
    • Balance: How evenly matched the players are in opening advantages.
    • Control: How much the game's outcome depends on the players' decisions rather than chance.

I don't see anything wrong with this. Some larger variants of chess look appealing at first, but end up being overwhelming. They feel artificial and it is hard to be invested in them. Playing Grand Chess reminded me of some CGI driven battle scenes from movies, where there is too much going on to care. Below is the variant known as double chess.  

Chess V, Gregory Strong

https://pychess-variants.herokuapp.com Gbtami

Capablanca Chess introduces two compound pieces. The Archbishop, which moves like a Knight and Bishop combined, and a Chancellor, which moves like a Knight and Rook combined. The board is 10x8. Does it work as a game? Kind of. It is not excessively large, and the compound pieces are logical. There is a problem of the undefended King's Knight's pawn, which could be fixed by simply changing the starting position, which Gothic Chess does. What is more problematic is that the Knights lose power due to the increased size of the board, and the Bishops gain power. This at least requires the players to rethink the pieces. The 10x8 board feels unnatural, too. The proportionality of the board, and the pieces on it, must matter a great deal. But I am not exactly sure what the proportions are supposed to be. What is clear is that much of what makes standard chess work is its proportionality . 

Seirawan Chess retains the 8x8 board, but allows the players to introduce two new pieces. In the position below, after I have moved my Bishop from its home square, I can introduce either a Bishop+Knight compound (the Hawk) or a Bishop+Rook compound (the Elephant). Sometimes the board feels a bit congested, but the game works well. 


I regard Omega Chess as one of the strongest variants, which is unfortunately neglected. The board is 10x10+4(!), and introduces two new pieces, the Wizard and the Champion. The pawns can move one, two, or three spaces on their first turn. This keeps things moving on the large board. The Wizards are very agile, moving one square diagonally or in large L shapes, like an augmented Knight). The champion moves one or two squares in any direction, but not diagonally one square. It also jumps, making it a very flexible piece. The additional corner squares seem to help the game's proportionality. 

Below is a game between Alex Sherzer and Judith Polgar. It is a fascinating struggle. 

Part of the reason I am hesitant to give any final pronouncements on proportionality is that a survey of chess variants reveals too many surprises. One interesting variant I found is 9x9, and it works much better than 10x8. Persian Chess cleverly borrows from Capablanca chess, Omega chess and from Shogi, which is 9x9. The pawns only ever advance two squares, and so the tension sits in the center row--but this is surprisingly playable. The compound pieces are Knight + Bishop, (the Princess), and Knight + Rook (the Fortress). In the diagrammed position, Black's Princess pins the Queen to the King. 

Anooshiravan Ahmadi

It is easy to confuse one's own preferences with objective facts. While I am no fan of variants with Elephants, Chinese Chess is the most played game in the world. It would probably have more players if it adopted Western pieces. So who is right? Perhaps Chinese Chess works so well because it balances relative powerlessness of the Elephants with pieces not present in Shatranj. 

I think there are objective facts about what makes a game work, and I think that the popularity of certain games should be explained in terms of the properties of the games. So what is the point of all of this? The point is that I think that Capablanca was right, and that chess, great a game though it is, is starting to lose its playability. It is still stronger than most of its competitors, but its advantages of balance and playability are being lost to its weaknesses like its lack of decisiveness. 

I am interested in what makes chess works, because I am interested in the properties that its successor will have. The possibilities are there, waiting to be discovered. To say all of this is not to attack Chess, anymore than the inventors of Chess attacked Shatranj. I doubt Chess will ever go the way of Shatranj. Currently all of the popular variants exist in a way that supervenes on Chess, and so Chess will always be essential. But I think the essential idea of Chess contains more than Sicilians, Spanish Openings, QGD's, and so on. 

I am very interested in your feedback, if you have made it this far. 

Here is the article I cited: