The German word “Zugzwang” means “move compulsion”. “Der Zug” is a chess move – it also means “train” – and “der Zwang” means “compulsion”. There is no equivalent English word for this concept, so chess players use the German word; and this word is widely understood by us, whether we speak any other word of German or not.
What would our game look like without the requirement to make a move on one’s turn? If a player could skip his turns freely, what would the game be? Well, I think I can tell you in one word—it would be a draw. Positions such as this one:
…would be hopelessly drawn. The black king just doesn’t move. Okay, it seems like a small deal. But also this position would be drawn:
And worst of all, so would this one:
So this means that to win a game, if the players are allowed to skip as many moves as they want, would require a huge difference in the level of the players. Basically it means that if Anand and Carlsen play each other, probably nobody is ever going to win. I suspect that it would even be tough for either of them to beat a 2300 under such rules.
Sometimes I have thought it a little artificial that so many positions are decided by just this – that a player is forced to move, even if he doesn’t want to, per the rules. In a real battle, you can stand still. You can wait for your enemy to come, or refuse to relinquish your position. In chess, there are positions where a player loses because his king has to step back and forth, Kg8-h8-g8-h8, etc; when he would rather just sit there. So does this make something in our game a little artificial?
But then I realized that no, this is in fact one of the areas where chess best mirrors life. In life, many problems could be solved if one could stand still at some point. You pause yourself when you are young and things are going well, the wrinkles haven’t started to appear. You often hear people talk about better times in their lives. So the question arises - why didn't they just keep things that way?
But that would not be life, that would be death. In chess it would be a draw death. The chess player has to make a move, just as there are forces making the world keep changing and forcing people to act, whether for good or bad. Physical aging, as well as the constant need for food and water and other needs, prevent one from reaching an ideal “position” and then standing still.
Now let’s see some puzzles in which the game is decided by one player’s fatal compulsion: