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#Post#: 848--------------------------------------------------
Even Chess
By: Steve Brown Date: April 23, 2018, 5:01 pm
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Imagine a duel between Adam and Bart, who stand a hundred feet
apart and take turns shooting at each other. Adam wins a coin
toss and shoots first. He has the advantage of the first shot
because if he kills Bart, he has had one more chance than Bart
had to kill his opponent. If Bart could somehow take a shot at
Adam after being killed, the duel would be fought on even terms.
An analogous situation exists with chess. If white checkmates
black, the game is over, and the number of moves white has
played exceeds the number of moves black has played by one. If a
game ends with "20 Qg7 mate ...", white has moved 20 times and
black has moved 19 times. White has the advantage of the first
move. This does not mean that chess is inherently unfair,
because in a match or tournament, players alternate playing
white and black. I devised a variant named Even Chess so that a
single game can be played on more even terms, not to make chess
more fair but to modify the game in new and interesting ways.
Even Chess allows black to develop more aggressively in the
opening and to have less reluctance to counter-attack, instead
of defend, when under attack by white.
Even Chess is played as orthodox chess but with a few changes to
the rules. The first is that the game ends only after both
players have made the same number of moves. Instead of
checkmate, the object is to capture the opponent's king. The
game ends after black's move when one or both kings have been
captured. If both kings are captured, the result is a draw. A
player is not required to get out of check but may respond to a
check on his king by placing the opponent's king in check, or by
making some other move. For example, if white places the black
king in check, black may respond by placing the white king in
check. If white then captures the black king, black may capture
the white king, and the game is a draw. White can avoid the draw
by getting his king out of check, leaving the black king in
check. Then if black does not get out of check, white may
capture the black king and wins if black does not then capture
the white king. Exposing one's own king to check, or leaving it
exposed to check, is a legal move. In the case where white
responds to a check on his king by checking the black king or
making some other move, he loses immediately if black then
captures the white king. In Even Chess, it is possible to
blunder into a loss by overlooking a check on one's own king and
making a move that does not parry the check. Announcing "check"
is not required but may be done as a courtesy.
Another rule concerns castling. In orthodox chess, a player may
not castle out of check. In the opening, an important
consideration is to castle before losing the right to castle
because of a check. Losing that right can inflict serious
weakness in the player's position. Playing one move behind
white, black is more susceptible to losing the right to castle,
so has to attend to king safety more diligently than white. That
gives white an edge in developing his pieces in the opening. In
Even Chess, that edge is countered by the rule that black, but
not white, may castle out of check or move the black king over a
square attacked by white. That gives black more latitude to
counter white's development in the opening, and it opens new
territory for opening lines to be explored.
Do the rules make Even Chess an equal game? That can be debated
and tested. Moving first is also an advantage in terms of
capturing material, because when white captures a piece, black
has one less piece with which to capture a white piece on the
same move. However, the rules may be adequate to compensate
black for that advantage.
#Post#: 849--------------------------------------------------
Re: Even Chess
By: John_Lewis Date: April 23, 2018, 5:34 pm
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King's Capture rules are not new, but this is the first time I
have seen Black given the chance to move an extra turn at the
end of the game as a way to reduce the first move advantage.
Further, the right to castle out of check or through check
dynamically changes how the game is played and is interesting in
its own right... does it result in parity for black and white.
I find the ideas both fascinating. However I fear they will not
compensate for White's initiative with their first move.
Perhaps restrict White so that their first move may NOT be a two
space pawn move? With this addition you might reach parity.
However you'd need a computer to test by playing millions of
games.
#Post#: 850--------------------------------------------------
Re: Even Chess
By: Steve Brown Date: April 23, 2018, 6:56 pm
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[quote author=John_Lewis link=topic=131.msg849#msg849
date=1524522849]
King's Capture rules are not new, but this is the first time I
have seen Black given the chance to move an extra turn at the
end of the game as a way to reduce the first move advantage.
[/quote]
Of course, black's guaranteed final move is "extra" only in the
sense of equalizing the number of moves for white and black.
[quote author=John_Lewis link=topic=131.msg849#msg849
date=1524522849]
I find the ideas both fascinating. However I fear they will not
compensate for White's initiative with their first move.
[/quote]
I thought of naming the variant "Equal Chess," but the goal is
not absolute parity but to give black more latitude to develop
aggressively and more incentive to counterattack.
[quote author=John_Lewis link=topic=131.msg849#msg849
date=1524522849]
Perhaps restrict White so that their first move may NOT be a two
space pawn move? With this addition you might reach parity.
However you'd need a computer to test by playing millions of
games.
[/quote]
Adding that to the existing rules could hand black an advantage,
;D
but that could be a rule in a different variant.
#Post#: 853--------------------------------------------------
Re: Even Chess
By: John_Lewis Date: April 23, 2018, 8:37 pm
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[quote author=Steve Brown link=topic=131.msg850#msg850
date=1524527787]
[quote author=John_Lewis link=topic=131.msg849#msg849
date=1524522849]
Perhaps restrict White so that their first move may NOT be a two
space pawn move? With this addition you might reach parity.
However you'd need a computer to test by playing millions of
games.
[/quote]
Adding that to the existing rules could hand black an advantage,
;D
but that could be a rule in a different variant.
[/quote]
Then maybe that's the only rule you need... again, you'd need to
test with something like LeelaZero.
#Post#: 861--------------------------------------------------
Re: Even Chess
By: Steve Brown Date: April 24, 2018, 11:52 am
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[quote author=John_Lewis link=topic=131.msg853#msg853
date=1524533876]
Then maybe that's the only rule you need... again, you'd need to
test with something like LeelaZero.
[/quote]
Restricting white's first pawn move to a one-square move is a
radical departure from orthodox chess in the opening phase of
the game. The intent of Even Chess is to be like orthodox chess,
but more even, not necessarily an equal game. Feel free to
create a variant with any rules and any name you like. You
would need a computer to play millions of games to ascertain if
equality is attained.
#Post#: 862--------------------------------------------------
Re: Even Chess
By: Steve Brown Date: April 24, 2018, 12:15 pm
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The Rules of Even Chess
1. The rules of orthodox chess apply, except as modified by the
following rules.
2. The object of the game is to capture the opponent's king. The
game ends when one or both kings have been captured, and both
players have made the same number of moves.
If one king is captured, the winner is the player whose king is
still on the board. If both kings are captured, the result of
the game is a draw.
3. When a player's king is in check, the player is not required
to get out of check and may make any move, including one that
attacks or captures the opponent's king.
4. A player may move his king into check and may use his king to
attack or capture the opponent's king.
5. Black, but not white, may castle out of check or, while
castling, move his king over a square attacked by a white piece.
#Post#: 866--------------------------------------------------
Re: Even Chess
By: Greg Strong Date: April 24, 2018, 10:14 pm
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This is an interesting idea. As far as I know, this approach to
mitigate white's first move advantage is new.
Unfortunately, playing for king capture removes stalemate from
the game. Stalemate is nice because it gives the losing player
something to play for.
You could, instead, address it like this... If white inflicts
checkmate, black may make one more move if and only if it
results in checkmating white. In this case the game is a draw.
#Post#: 870--------------------------------------------------
Re: Even Chess
By: Steve Brown Date: April 25, 2018, 12:43 pm
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[quote author=Greg Strong link=topic=131.msg866#msg866
date=1524626086]
This is an interesting idea. As far as I know, this approach to
mitigate white's first move advantage is new.
Unfortunately, playing for king capture removes stalemate from
the game. Stalemate is nice because it gives the losing player
something to play for.
You could, instead, address it like this... If white inflicts
checkmate, black may make one more move if and only if it
results in checkmating white. In this case the game is a draw.
[/quote]
Now it gets complicated. In orthodox chess, the purpose of the
rules regarding check and checkmate is to ensure a "proper" end
to the game, where one player inflicts on the other the
condition in which he cannot get his king out of check, a
condition in which the king cannot avoid being captured if that
were a legal move. Under those rules, a player cannot blunder
into a loss by leaving his king en prise, because doing so would
be an illegal move. Therefore, it is illegal for a player to
leave his king in check or to move it into check, raising the
possibility of stalemate, a condition in which a player has no
legal move. With careful play, stalemate can be avoided, so
stalemating the opponent is a blunder. Ironically, if capturing
the king were the object of the game, the condition known as
stalemate would be zugzwang, in which a player would have no
better move than to expose his king to attack. In that case,
stalemate is not a blunder but a desirable condition to inflict
on the opponent. So while the rules of check and checkmate are
to prevent a player blundering his king away, those same rules
make it possible for a player who has a winning position to
blunder into a draw. In my view, the zugzwang interpretation is
more logical than the stalemate interpretation of the position
in which a player has no legal move.
You proposed the rule "If white inflicts checkmate, black may
make one more move if and only if it results in checkmating
white. In this case the game is a draw." The problem with that
rule is that it does not allow black to respond to checkmate by
putting the white king in check. Under the existing rules of
Even Chess, black doing that leaves white with two options:
1. White captures the black king, black captures the white king,
and the game is a draw.
2. White gets his king out of check, leaving the black king in
checkmate.
After option #2, black can still check the white king.
Theoretically, the game could go on for several more moves while
black is in a checkmated position, by continuing to put the
white king in check. At some point, black runs out of checks, in
which case he loses on the next move when white captures his
king and black cannot capture the white king, or he succeeds in
checkmating the white king. In the latter case, white captures
the black king on the next move, black captures the white king,
and the game is a draw.
Still, stalemate can be preserved in Even Chess by adding a
somewhat arbitrary rule:
6. If a player whose king is not in check cannot move without
putting his king in check, the game is a draw.
As I wrote in the first paragraph above, I believe the zugzwang
interpretation of the stalemate position is more logical, and it
is consistent with rule #4, that a player may move his king into
check. However, in the spirit of collaboration, I leave it up to
members of this forum to decide whether to add proposed rule #6
to the rules of Even Chess. Another possibility is that rule #6
could be optional. Eventually, the majority opinion will be
respected.
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