This introduction is written for the problem-solving competition in the 2007 Australian Junior Chess Championships.
In this type of problem, a position is set up and the solver has to find White's first move (called the key-move). Whatever move Black then plays (these are called defences), White must have a move (his second move) that gives check-mate. In some competitions, the solver is asked to write out all the variations (such as if 1...ef 2.Nd3 mate), but in this competition you only need to write down the key-move. But you will need to work through all the defences to make sure your key-move is correct. Here is an example:
The solution is: 1.Nf6.
Let us check that it is correct: after the key-move White is threatening 2.N6d7 mate. How can Black defend against that?
1...KxN, 2.Rd7 mate
1...QxN, 2.f4 mate
1...f4, 2.Rd5 mate
If Black tried any other defence, the threat would still work.
How could we have solved that problem? One method is to try each possible White key-move one by one and see whether it is the solution. That could be called a "brute force" method. It will certainly work, but requires a lot of care to avoid missing something along the way, because we tend to assume things that aren't so; it is also a boring method, because it doesn't reveal any interesting relationships in the position. Another method is to study the position to see what is important in it; that is what the composer intended that we do. After a good deal of familiarising ourselves with the position, we might see that 1.Nd7ch would give mate except that Black has the defence 1...Ke6 and then there is no mate to follow on White's second move. Next, we might think that the other N could mate on d7, because then e6 would still be guarded by the N on f8. That suggests 1.Nf6. We might not think of that move in a game of chess at all, because the N can be captured on f6, in fact in two ways. But this is not a game of chess; in problems we throw away all the principles we learned in playing the game, and we only need to know how the men move. The reason is that in a game of chess it doesn't matter how many moves it takes to win, but in this problem we have to do it in just two moves. So moves can arise in problems that would seem strange and unnatural in a chess game. They may be described as "paradoxical" or "counter-intuitive", big words which I leave you to look up in a dictionary if necessary. Examples are withdrawing a man from an apparently strong position, freeing a Black man that was pinned, making a move that at first sight seems to have no purpose, or allowing your King to be checked. In fact, it is almost certain that the key-move will not be an obvious or strong-looking one. Whichever of the two methods you use (or a combination of them), you will need to be aware of all the possible moves for both sides, so a good "sight of the board" is needed.
In this problem the key-move had a threat (2.Nd7), but in some other problems White makes no threat but just waits.
Whatever move Black makes, White has a move that gives mate. Here is an example; the solution will be given later, so that you can try it yourself first:
You might wonder why people are interested in chess problems, because they are different from a game of chess. The main answer is that problems are artistic; that means they are beautiful, neat, satisfying, surprising, subtle, and so on. In that way, they are a bit like music, painting, poetry or other arts. Apart from that, they are a good mental challenge, and can free you up from routine thinking and from assuming things that seem obvious at first but might not be so obvious after all.
In many problems you have to be careful because there are some good "tries". A try is a key-move that doesn't quite work because there is a successful defence, which may be well hidden.
You might have wondered whether there are any other solutions to (1). The answer is no, and it would be good to check that by looking briefly at all the other possible key-moves. If there had been two or more solutions, the problem would be called "unsound" or "cooked", and the other solutions would be called "cooks" (apparently no one knows why that word is used, although there are some theories). Unsound problems are not wanted, and there won't be any in this competition.
A problem is composed by someone, in this case A. Munck in 1901. Composing a sound and beautiful problem is generally quite hard work, but very satisfying if you succeed. There are thousands of problem composers in the world, and millions of solvers; there has been great interest in it for hundreds of years. It is natural to learn to play the game of chess first, but after you've done that you might like problems as well.
Now here's another for you to try, without any comments; the solution will be given later, so that you can try it yourself first:
And here's another; the solution is not given here:
If you want to find out more about "mate in 2 moves" problems, or to find some to practice on, you could look here:
A good book is: Solving in Style by John Nunn, and there are many others.
Some problems ask you to mate not in 2 moves but in 3 moves, or even more moves than that; then they can become quite complicated.
In this competition we might have one or more 3-movers, but probably none with more than 3 moves.
For 3-movers, the brute force method is less likely to work (unless you are a computer), because there are too many variations to work through.
Here's an example:
It soon becomes clear that the key will be a move by the WK, and not to a black square. But which square will work: h5, h3, f3, or f5? It turns out that it must be 1.Kf5. Then 1...Be5 2.h8=Qch Bxh8 3.f8=Q mate or 2...Bb8 3.Qh1 mate. If we tried 1.K-another white square, then 1...Bd6! and after 2.h8=Qch Bb8 White's Q will not be able to mate on h1.
For more about "mate in 3 moves" problems, try: http://www.bcps.knightsfield.co.uk/threemovers.html (keeping in mind that specially difficult ones will not be set for this competition).
Studies (which usually means end-game studies) are sometimes closely related to what can arise in chess games, but studies are refined and reduced to their essentials.
Studies are, like problems, attempts to create something artistic on the basis of the rules of chess.
Problems such as "White to play and mate in two moves" obviously require a definite number of moves,
but studies do not require a definite number of moves.
A position is set and the challenge is usually either: White to play and win; or: White to play and draw.
Here is an example:
Here it looks as though Black is going to promote to a Q and then win easily simply by his material advantage. In a game, White might mistakenly resign. But the challenge to draw forces White to look for a hidden possibility. The only way to try to prolong the game is 1.Ra1ch Kb8 2.Rb1ch Kc8. Then 3.Re1 would threaten 4.Re8 mate, buf after 3...Kd8 White would have no further way to prolong the game. So 3.Ra1 threatening 4.Ra8 mate. Then Black does not want to draw by repeating moves with 4...Kb8, so he will play 4...Kd8. Now the only attempt is 5.Kd6 again threatening mate. So 5...Ke8 6.Ke6 Kf8 7.Kf6 Kg8. Now White cannot play 8.Kg6 because of 8...g1=Qch, so he must play 8.Ra8ch. The same procedure will now take place with movement in a different direction: 8...Kh7 9.Ra7ch Kh6 10.Ra8 Kh5 11.Kf5 Kh4 12.Kf4 and Black must now retrace his steps with 12...Kh5 (obviously not 12...Kh3 13.Rh8 mate). Black can never get time to promote a pawn, so it is a draw.
To solve a study by a brute force method is usually not likely to work because there are too many possibilities involved, so we have to reason it out.
Here's another example:
After 1.h8=Q a1=Q 2.QxQ would be stalemate. White will therefore now try to bring about a discovered mate along the back rank. The solution is given later.
Studies are composed so that it seems at first sight that there could be no solution; therefore you have to look deeply for hidden possibilities. Often there will be a main line and side lines, as in the analysis of a chess game. For this competition you will only need to give the main line or lines, not all the minor details.
For more examples you could look here: http://www.bcps.knightsfield.co.uk/studies.html (again keeping in mind that specially difficult ones will not be set for this competition).
(You don't have to follow this advice, of course!)
1. You can solve from the supplied diagram or you can set the position up on your board. If you set it up, make quite sure you've got it right, so as to avoid wasting time on a wrong position. If you set it up and move the men while solving, you'll have to be careful to replace them correctly, so it may be best to avoid moving them unless you find it necessary. It will probably not be necessary to move the men in "mate in 2" problems, but in "mate in 3" problems and in studies you might find it necessary.
2. For each problem the number of marks will be indicated. It's probably best to start with the problems with lower marks, assumed to be easier. Otherwise, you might spend a lot of time on a harder problem and not solve it, thus not earning any marks.
3. Although the time taken is important, so you can get the highest possible score (also ties will be broken by time taken), it might be best not to rush into it. An attempt to solve a problem quickly might result in your missing the solution altogether, so the time would have been wasted. Calm reasoning is best.
4. If you think a problem has no solution or has more than one solution, write that down in your answer, but check carefully first, because it not intended to set any such problems, so it is extremely unlikely to occur.
(2) 1.Kd6 (waiting). You should find out why any other move of the WK would not work.
(3) 1.Qa8 (waiting).
(7) 1.h8=Q a1=Q 2.Qg8 Qa2 3.Qe8 Qa4 4.Qe5ch Ka8 5.Qh8 and now 5...Qa1 6.QxQ is not stalemate but leads to mate next move. (2.Qe8 would have been answered by 2...Qg7.)
Great satisfaction is obtained by some people from solving or composing chess problems or studies. The first step is always to solve a lot of them, which is what you'll be doing here. Australia has some of the best solvers, including Ian Rogers. Later you might become interested in composing; Australia also has some of the best composers in the world, including Peter Wong.