Zugzwang, that dreaded compulsion to move when your position is so stretched that anything you do will weaken it, can be a chess player's nightmare, but there are occasions when it poses no problem at all.
In it's most elementary form, zugzwang is deadly. In this simple endgame position either side to play loses first the pawn, then the game.
We've all seen it.
The next game (Saemisch—Nimzowitsch 1923) has been described a “The Immortal Zugzwang Game” and Saemisch is faced with a dilemma. Black's last move has deprived the white queen of her only escape square. Now, if 26.Bc1 to create some lebensraum the knight on b1 is left without protection. If anything else, Nimzowitsch threatens 26...R(f5)f3 winning queen and bishop for a pair of rooks. Is this a true zugzwang? That's debatable. To my mind zugzwang implies that the compulsion to move must weaken the position, but in this case, even if Saemisch had been able to sit without moving, Nimzowitsch's options would have remained the same.
(The notes to the game are by Nimzowitsch himself.)
So let's look at a zugzwang from one of my own games—and this position is typical of those zugzwangs that don't matter a bit. And why not? Because when you have a lost game it doesn't really matter if things get worse. It may even be an advantage to put your king out of his misery a little more quickly and bring an end his suffering. Think of it as euthanasia, chessboard style—Caissa's mercy.
This is the game I mentioned in the final section of my January 9 post—Play Taller Chess— and it hasn't progressed very far in the past five weeks.
What is Black to do? If the king moves the knight dies; if the knight moves the pawn dies; if the pawn gives check it dies in vain, for the check achieves nothing; if the knight bravely lays down his life with 59...Nxe4 clearing a path for his lone pawn it is a futile gesture for White's knight, bishop and king all have the path to the queening square well-covered.
So, we have a genuine zugzwang but since White is already a piece and two pawns to the good, winning the game is only a matter of time.
(You can see the whole game HERE.)
Why does Black play on? In Alexander Pope's words, “Hope springs eternal...” In this case that hope probably resides in my white-square bishop, the black square on h8, and fingers crossed hoping for a stalemate in the corner.