Check, checkmate and stalemate

White has a queen and a king against a lone black king in the corner. On the first board the queen stands on g7, on the second on g6, one square lower. In the first position White won. In the second the game ended in a draw.

In both positions it is Black's move, and in both Black has nowhere to go: White's queen and king attack the three squares around the king on h8. There is one difference. The queen on g7 attacks the king, and the queen on g6 does not. The first case is called checkmate, the second stalemate, and this chapter is about telling them apart.

The first chapter mentioned check and mate briefly, and in the chapter on the pawn you met stalemate in the Saavedra position. Now you know how all six pieces move, so we can work through these rules properly: how to answer a check, what happens when there is no answer, and what happens when you have no move but are not in check.

Check

When an enemy piece attacks a king, the king is in check. In a game record, check is marked with + after the move. Any piece except a king can give check: kings, as you remember from the third chapter, never stand next to each other.

You must answer a check at once, on your very next move, and you have no other business that turn. The rules forbid any move that leaves your king in check, and the board will not let you make one. There are only three answers:

• move the king to a square the opponent does not attack;
• capture the piece that gives check;
• block: put one of your own pieces between the king and the piece that gives check.

First you have to see who is giving check. Usually it is obvious, but beginners miss a check from far away along a long diagonal all the time.

Notice that one piece gives check but three pieces do the work. That is almost always so: a check is dangerous together with the squares that other pieces have already taken from the king. This is why beginners often give check for nothing. The king steps to a free square, the checking piece stands where it has nothing to do, and a move has been wasted. Before you give check, look at what the king will have left afterwards and what your piece will do next.

Moving away

From here we work with one position, as in a laboratory: we change one detail at a time and see which answer to check appears. A white rook has come to e8 and gives check to the king on g8 along the eighth rank. You saw a similar position in the first chapter, when you gave the mate Ra8#. In front of the king stand its three pawns, f7, g7 and h7, and White has a king and three pawns at the bottom. We will see how the position ends as it stands in the section on mate. For now we move two black pawns one step forward and put a white bishop on b2.

On the line of check there is a square that is easy to take for safe: the square behind the king. While the king stands still, it shields the far part of the line from the rook, and it seems quiet back there.

And one more trap. Sometimes an enemy piece cannot move because it is shielding its own king. It still attacks its squares as before, and a king cannot step under its attack. The FIDE rules say so directly: a king is in check even if the checking piece cannot move itself.

Capturing

The second answer is to capture the piece that gives check. Any piece that reaches it can do so, the king included, with the proviso from the first chapter: it does not take a defended piece, because after the capture it would be under attack.

Capturing is the most profitable answer when it is possible and safe: the checking piece disappears from the board, and the threat goes with it. But sometimes a piece reaches the checking piece and still cannot capture it. More about that in the section on mate.

Blocking

The third answer is to put your own piece on the line of check, between the king and the piece that gives check. You can block with a piece that is taken at once: the check is still answered, and the game goes on. If you have a choice, block with a cheaper piece or with one that another of your pieces defends: then the opponent, if they capture it, will give up a piece of their own in return.

You cannot always block. You need a line with empty squares between the piece and the king. So you can block a rook, a bishop or a queen if they give check from a distance. You can never block a check by a knight: it attacks with a jump, and there are no squares between it and the king. We saw this in the third chapter. You cannot block a check from next door either, a pawn's included: it gives check from the neighbouring square diagonally. In such cases only two answers are left: move away or capture.

Now we put all three experiments together. Black has both the knight and the bishop, and the h7 pawn is moved to h6, so the king has a square to step to as well.

Double check

A check can come from two pieces at once. This is double check. In one move you can capture only one piece or block only one line, and the other piece will still be giving check. So against a double check there is a single defence: move the king. If it has nowhere to go, that is mate.

How do two checks arise in one move? A piece leaves a line along which another piece of the same colour looks at the enemy king, and the line opens. A check from a piece that did not move itself is called a discovered check, and chapter 14 will explain it in detail. If the piece that moved also gives check, there are two. Double check is one of the strongest attacking ideas: the opponent has no time to capture or to block, and even a queen given up for it often pays off.

Let us see how it looks on the board. The position is a teaching one: a white bishop stands on e2 and blocks its own rook's way along the e-file, and a black king stands on e8, at the end of the file.

Black's rook on b8 could have taken the bishop, and the knight on f6 could have blocked one of the lines. Check whether that would have helped.

One of the most famous double checks, from the game Réti – Tartakower (Vienna, 1910), is covered in chapter 7.

Now give a double check yourself. The rook on e1 looks at the black king through its own knight.

Checkmate: all three answers closed

If a king is in check and none of the three answers is available, that is checkmate. The game ends that second, and the side that delivered it wins. In a game record, mate is marked with #.

Let us go back to the laboratory, to the position with no experiments: the pawns on f7, g7 and h7 in place, no knight and no bishop.

To check whether it is mate, ask three questions in order. Where can the king go? What can capture the checking piece? What can block? You must not skip any. People go wrong on the first when they forget the square behind the king on the line of check. They go wrong on the second when they do not see that the piece that could capture is itself shielding its own king.

Now find a mate yourself. White has several checks, and you should test each with the three questions.

Mate in one is worth looking for in every position, and the skill can be trained. The trainer shows a position where a mate exists, and you find it. Keep solving until the three questions start asking themselves.

Stalemate

Now the reverse case. There is no check, but there is nothing to move either: the opponent attacks every square next to the king, and there is no other move, with a piece or with a pawn. This is stalemate, and the game ends at once in a draw. You may not pass, you may not step under attack, and the game simply stops. However many extra pieces the opponent has, stalemate gives them no win.

Look again at the positions from the start of the chapter. With the queen on g6 the king on h8 is locked in as tightly as with the queen on g7: it has no move at all. But the queen on g6 does not attack the king. So this is not mate but stalemate.

The whole side must have no moves, not only the king. If it has even one move anywhere on the board, a pawn move on the edge included, there is no stalemate.

Why is stalemate a draw and not a win for the stronger side? That was agreed, and not all at once. In England in the 17th and 18th centuries it was the other way round: whoever stalemated the opponent lost the game. There stalemate became a draw only in the early 19th century, following French and Italian custom, and today the rule is the same everywhere. In a tournament a win scores a point, a loss nothing, and a draw half a point for each player. In a game record these are 1-0, 0-1 and ½-½; there is more about this in chapter 7.

For the player who is winning, stalemate is the main danger. It happens most often at the end of a game, when the opponent has only a king left, or a king with blocked pawns. It is especially easy to stalemate with a queen: it takes many squares from the king at once, and the last one can be taken without giving check. The habit here is simple: when the opponent has almost no moves left, count before each of your moves how many will remain for them afterwards.

Now play it out yourself, against the engine. The black king in the corner has three squares left, and the most natural queen move takes all of them at once without giving check. Before each move ask yourself: will Black have a move left?

Stalemate as a rescue

If stalemate is a danger for the side that is winning, for the side that is losing it is a hope. When a game is lost, look for a way to be left with no moves at all. One of the best-known cases happened in New York, at the US Championship of 1963/64. Larry Evans played White against Samuel Reshevsky, and Black was a knight for a pawn up, in a winning position. English-speaking players call the game "the Swindle of the Century".

A rook that gives itself up on every move and cannot be taken without stalemate is called a desperado, or a rampaging rook. In this game Reshevsky opened the road to stalemate himself: the move 48...Qxg3 is a blunder and earns two question marks, and the winning move was 48...Qg6: the queen leaves the pawn's attack, and Black keeps the extra knight. Now find such a rescue yourself, in a simpler position.

What's next

Now you know the three answers to check and can tell mate from stalemate. But stalemate is not the only draw. There are others: threefold repetition, the fifty-move rule, insufficient material, such as a king and a knight against a king from the third chapter. The king also has a special move, castling, and it has its own conditions: when you may castle and when you may not. All this is in the chapter "Castling and draws". How to give mate to a lone king with a queen or a rook by a plan, without hoping for an error and without stalemating, is taught in chapter 9.