Perpetual Check

Have you heard of “perpetual check?” What is it? Do you know what the word “perpetual” means?

When you don’t know what a word means, you can always look in the dictionary. Let’s see what the dictionary says:

Perpetual

Pronunciation: per-'pech(e-)wel, -pech-el
Function: adjective
1 : continuing forever : Everlasting 
2 : occurring continually :  Constant
- per·pet·u·al·ly /-/ adverb 

“Perpetual” means something that goes on and on and on, forever. So a perpetual check is when one player gives a check, the opponent gets out of the check, but then comes another check, and another, and another. It would go on until the end of time if the rules of chess did not stop the game.

Why would you want to give a perpetual check? Well, let’s check out this position:

White is down a lot of material. Specifically, he is down a rook, the “exchange” (a rook for a knight) .Normally Black would win easily. But at this point, White has a chance to give a perpetual check, which will be a draw. A draw is better than a loss!

1. Nc7+ Ka7 2. Nb5+ Ka83. Nc7+ Ka7 4. Nb5+ Ka85. Nc7+

Does White have to give perpetual check in the above position? No, he doesn’t. But he should. If he doesn’t give perpetual check, then Black will win if he even plays halfway decently. So really White does have to give perpetual check if he doesn’t want to lose, and of course Black cannot get out of check.

When someone is in perpetual check, how does the game end? Or are the players stuck there, repeating moves forever? 

Well, normally the player in check will realize after a few repetitions that he cannot get out of check and will agree to a draw. If he doesn’t, then you just wait for the same position to occur three times. Then you can claim a draw on the “threefold repetition” rule. So if you get into perpetual check in chess, don’t worry: you don’t have to stay there until the sun goes down!

Now try to find the way to make a perpetual check in these problems: