[chessmind] Dennis Monokroussos: Chess is not Checkers - Thankfully!

[Email subscription to blog articles]

Posted by Dennis Monokroussos:
Chess is not Checkers - Thankfully!
http://chessmind.powerblogs.com/posts/1184915335.shtml


   I've used that phrase with chess students before, to emphasize that in
   chess, unlike checkers ("draughts" for at least some non-Americans),
   captures are not mandatory. It behooves one to be on guard for
   possible zwischenzugs, both for oneself and for the opponent. That's a
   useful lesson, but it's not the subject of this post.
   Rather, it's this: word came down the pike yesterday that checkers is
   officially solved ([1]here and [2]here; HTs to Rob Bernard and Michael
   Bagalman, respectively). (That game is objectively a draw, in the
   unlikely event anyone suspected otherwise.) That paltry feat only took
   18 years of working through 500 billion billion positions (ho hum);
   chess, on the other hand, has around a billion billion billion billion
   billion possible positions (so says the first article - I'll take its
   word for it, as trying to count them myself might keep me up past my
   bedtime).
   Thus we're safe for now, as Tim Krabbé is always fond of pointing
   out. In his most recent [3]Chess Diary entry (#344, "The Helplessness
   of the Pair of Queens"), he presents the game Kosten-Zelcic, in which
   White reaches a position with two queens and a pawn against a mere
   rook, bishop, knight and three pawns - but can't win. Despite the
   apparent obviousness of the blockade, none of the current programs,
   including [4]Rybka, the current king, is even remotely able to
   recognize this. (Ironically, if the game score given both on Krabbé's
   site and on [5]chessgames.com is right, White probably missed a win
   with 76.Qc7. Whether White can force that sort of winning position
   without help is another story.)

References

   1. http://news.bbc.co.uk/2/hi/science/nature/6907018.stm
   2. http://www.nytimes.com/2007/07/19/science/19cnd-checkers.html?ex=1342497600&en=d369b9138fd850b6&ei=5088&partner=rssnyt&emc=rss
   3. http://www.xs4all.nl/~timkr/chess2/diary.htm
   4. http://www.rybkachess.com/
   5. http://www.chessgames.com/perl/chessgame?gid=1278811