56
votes
Accepted
Why did this legendary game of Carlsen vs Nakamura not trigger threefold-repetition after move 5?
While the position might seem like it has been reached 3 times at that point, that is actually only the second time they have reached that position because the first time they were in this position, ...
- 829
54
votes
Accepted
Why is flagging considered a win?
I feel like you somewhat misunderstand the concept of a time control. The clock is a part of the game. If you are up a piece in a complicated position with five seconds left on the clock that may well ...
- 3,391
26
votes
Why is there no rule allowing a player to claim a draw in lonely king endgames?
Why is there no rule allowing a player to claim a draw in lonely king
endgames?
For the simple reason that there is no need. If you are the player with the extra material you can offer a draw and be ...
- 94.5k
25
votes
Accepted
Should an arbiter claim draw at a K+R vs K+R endgame?
You can declare a draw and in fact you are required to declare a draw but only after you have counted 75 moves by each side without a capture or a pawn move. This is according to the FIDE Laws of ...
- 94.5k
25
votes
Accepted
Moving into check for a draw as black, why is it illegal? Comparison to Racing Kings
Imagine a variation of chess without the rules about check and checkmate, where a player wins simply when he captures his opponent's king. In this variation, Kxd5 loses the game to exd5.
Turns out, ...
- 532
25
votes
Why is flagging considered a win?
Let's look at the title question from the perspective of engine chess, which is more objective in the sense that you can get two engines to play tens of thousands of games against each other at ...
- 26.1k
20
votes
Why is flagging considered a win?
Because not having it would result in some perverse incentives. In particular, in any game where a draw is an acceptable outcome, the optimal strategy without flag drops being losses would be to never ...
- 391
18
votes
Moving into check for a draw as black, why is it illegal? Comparison to Racing Kings
Those are just the rules of the game. You could absolutely try to make the case that moving into check in such a situation should be legal, but playing by those rules wouldn't be chess anymore (it ...
- 19.8k
17
votes
Moving into check for a draw as black, why is it illegal? Comparison to Racing Kings
I will answer from a different perspective: why Racing Kings (RK) has a rule to allow black a chance to draw, and why the same logic doesn't apply to chess.
What is Racing Kings (RK)?
Background for ...
- 4,980
16
votes
Should an arbiter claim draw at a K+R vs K+R endgame?
It is not a drawn position according to the rules, since there is sufficient mating material. It may be a draw from the point of view of endgame theory, but given players who make lots of mistakes, it ...
- 10.5k
16
votes
Accepted
Rules: Is this position a draw?
This is a better question than it seems at first glance.
Intuitively it seems possible to claim a draw, since the position appears to have occurred three times.
However, according to a strict ...
- 4,980
16
votes
Accepted
Does a draw on the board need to be declared before the time flag is reached?
There are three articles in the FIDE Laws of Chess which are relevant here:
5.2.1 The game is drawn when the player to move has no legal move and his king is not in check. The game is said to end in ‘...
- 94.5k
15
votes
Does a draw on the board need to be declared before the time flag is reached?
This was undoubtedly a draw. FIDE rules, emphasis mine:
5.2.1 The game is drawn when the player to move has no legal move and his king is not in check. The game is said to end in ‘stalemate’. This ...
- 27.7k
13
votes
Accepted
Does threefold repetition apply in a rapid game?
TL;DR: Claiming draws based on threefold repetition or the fifty-move rule is possible in rapid and blitz games as well. Contrary to RemcoGerlich's answer, it is not strictly necessary to record the ...
- 1,789
13
votes
Accepted
Is it OK to look at the list of played moves during the game to determine the status of the 50 move rule?
The rules for this and how it works are spelled out in articles 9.3, 9.4 and 9.5 of the FIDE Laws of Chess. They don't mention whether or not you are allowed to check your scoresheet to do this ...
- 94.5k
13
votes
Accepted
Was this a valid draw?
No, it was not a draw. For a draw by three-fold repetition, the exact position, and all of the possible moves (castling and en passant, which since en passant can only happen on the move, in essence, ...
- 32.4k
13
votes
Why is flagging considered a win?
Since you specifically asked for historical reasons: Think about your two proposed criteria in the context of the year 1800 or 1900.
Using engine evaluation is obviously out of the question. So is &...
- 5,908
12
votes
Do the rules of chess state that a Bishop+King can be sufficient mating material?
First, Carlsen, despite having only the Bishop, WON that game. So it is not about mating material, but about ANY possible mating position, and there was one here.
The rule at hand is this:
...
- 32.4k
11
votes
Accepted
Can Loss by Checkmate be Avoided by Invoking the 50-Move Rule Immediately After the 100th Half-Move?
Can player B invoke 9.3.2 to avoid the loss by checkmate?
No.
A player can only invoke the 50 move rule if the game is still being played. Checkmate ends the game. Once the checkmate is on the board ...
- 94.5k
10
votes
Accepted
Can you claim a draw, after the position has changed, if threefold repetition occurred earlier?
(I consider the FIDE rules to be the "the rules of chess" and this answer is only about them)
No, you cannot claim. In fact your right to claim ends as soon as you touch a piece.
Here's what ...
- 27.7k
9
votes
Why is flagging considered a win?
Except for exceptional circumstances, only three results are considered valid for a chess game (and the corresponding rating change): win, draw or loss.
Your suggestion would come with a huge problem: ...
- 16.3k
9
votes
What happens in a King-Rook vs King-Bishop with a perfect play in a no pawn endgame?
See Pawnless Chess Endgame on Wikipedia:
Rook versus a bishop: this is usually a draw. The main exception is when the defending king is trapped in a corner that is of the same color square as [their] ...
- 26.1k
8
votes
Why is flagging considered a win?
It's considered a win because that is what it is by definition from the rules of timed games.
When you enter a game you commit to its rules; in this case one of those rules is that the time you have ...
- 279
8
votes
Accepted
When can a player with just a bishop/knight vs overwhelming material claim a win on time?
When can a player with just a bishop/knight vs overwhelming material claim a win on time?
A win on time can be claimed when it is possible to "checkmate the opponent's king by a series of legal ...
- 94.5k
8
votes
Accepted
What happens after repeated incorrect draw claims?
Can he stop the clock and call the arbiter?
A player can always do this. However, according to the rules:
6.11.4
If a player stops the chessclock in order to seek the arbiter’s assistance, the ...
- 94.5k
7
votes
Accepted
how does a uci engine draw or resign?
UCI chess engines don't offer/accept a draw, nor resign a position. This is the GUI's responsibility.
You are welcome to add new uci options (setoption and option) for your engine, but don't expect ...
- 22.4k
7
votes
Does a draw on the board need to be declared before the time flag is reached?
That's an easy one: stalemate ends the game automatically. FIDE 5.2.1. rule. Neither flag, nor handshaking, nor signing the scoresheet change this. What to do: 1. Play safe, inform an official. 3., ...
- 15.4k
6
votes
Does the FIDE 75-move rule apply after checkmate or resignation?
The FIDE Laws of Chess (I'm giving a link to the version in the Arbiter's Handbook because FIDE have Munged their own site) do give a definitive answer but it takes some searching to find. The key ...
- 94.5k
6
votes
Should an arbiter claim draw at a K+R vs K+R endgame?
It's better to let them play it out a bit and ideally only draw once reaching 50 moves. But if one of them is low on time (and their opponent is clearly just trying to flag them) then you should claim ...
- 19.8k
6
votes
Accepted
Does the FIDE 75-move rule apply after checkmate or resignation?
Here is my email conversation with the head of the FIDE Arbiter's Commission, Laurent Freyd.
In essence, for now, until they add a clarification, and arbiter would be correct ruling either way. That ...
- 32.4k
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