HDTenEightyP/NetNews huggingface dataset:
From: trodrigu@spock.ecs.umass.edu (Tao R or Stephen L)
Subject: Re: defects in abstract games
Summary: Not really Nim
Organization: University of Massachusetts, Amherst
Date: Thu, 7 Jan 1993 04:58:14 GMT

> that would be a sad thing - Twixt reduced to Nim....it might be true
> though...we need one counter-example - a game that ends finitely and
> cannot be reduced to solving an equivalent Nim or Sprouts problem.
 
'Luckily', having checked the book, I now believe Kevin Whyte has this
right and I was wrong.  There seems to be no particular reason to think
that Twixt can be reduced to Nim.
 
On the other hand, it occurs to me that Traxx (when it is played without
the 8x8 restriction) may require a rule defining draws.
 
- Stephen
Newsgroups: rec.games.abstract
Subject: Re: defects in abstract games
From: wft@math.canterbury.ac.nz (Bill Taylor)
Date: Fri, 8 Jan 1993 02:20:36 GMT
Organization: Department of Mathematics, University of Canterbury
Keywords: Hex

In article <1993Jan6.154514.8642@infodev.cam.ac.uk>, cet1@cus.cam.ac.uk (C.E. Thompson) writes:
|> 
|> Indeed, a winning advantage (by strategy stealing) with perfect play.
|> Is it a "defect" that one knows what the result of the game should be
|> even if one cannot actually execute a strategy to achieve it?

The answer is "3-move equalization", without a doubt; as I have enjoined
readers many times already.

Then neither player knows for certain who has the theoretical winning advantage,
though both still know (of course) that one of them must have it.

Let's hear it for THREE-MOVE EQUALIZATION !!
                  ~~~~~~~~~~~~~~~~~~~~~~~
-------------------------------------------------------------------------------
              Bill Taylor              wft@math.canterbury.ac.nz
-------------------------------------------------------------------------------
Both false:  This sentence contains seven words.
             This sentence does not contain seven words.
-------------------------------------------------------------------------------
From: kleber@husc11.harvard.edu (Gwydden)
Newsgroups: rec.games.abstract
Subject: Re: Mornington Crescent?
Date: 5 Jan 93 19:40:58 GMT

blom@husc15.harvard.edu writes:

> > What is Mornington Crescent?
>
> Players take turns naming London subway stops.  The first person to name
> Mornington Crescent wins.  Of course, you can't say it too soon or it's no fun
> to play with you . . .

This is an extremely simplivied version of the game, though...
moves are determined by a very strong aesthetic sense of what
is a "good move"; while these aren't rules, just conventions,
they are universally understood and a good player must work within
them to gain any respect.  See the group alt.games.mornington.cresent
(yes, spelled wrong) for some excellent playing.
From: blom@husc15.harvard.edu
Newsgroups: rec.games.abstract
Subject: Re: Mornington Crescent?
Date: 5 Jan 93 18:04:01 GMT
Organization: Harvard University Science Center

In article <1993Jan4.160110.1@vax1.umkc.edu>, dnicol@vax1.umkc.edu writes:
> What is Mornington Crescent?

Players take turns naming London subway stops.  The first person to name
Mornington Crescent wins.  Of course, you can't say it too soon or it's no fun
to play with you . . .
From: dbush@csugrad.cs.vt.edu (David Bush)
Newsgroups: rec.games.abstract
Subject: Re: defects in abstract games
Keywords: chess, draws
Date: 11 Jan 93 21:34:02 GMT
Organization: Virginia Tech Computer Science Dept, Blacksburg, VA

baarniy@iastate.edu (Scott A Coon) writes:

>>what if you win the game if you can promote your king to the 
>>8th rank? 

>>Many of those "book draws" when the material dwindles 
>>sufficiently, are now suddenly up for grabs.
>>
>>- nate


>    The thing is, in an unbelievable number of endgames,
>the person who wins is the one who is able to sneak behind
>his opponent's pawns with his King, so he can attack them from 
>the rear (they can't move any faster than he can, so this is effective.)
>   If you have to prevent the King from getting behind your pawns
>in order to hold a drawn endgame, you obviously can't let him get
>access to your back rank, which is also behind your pawns.  I'm afraid
>that this quick-fix is really going to make almost no difference
>whatsoever.  Sorry.

>Scott
>baarniy@iastate.edu

I disagree. If getting your king to the 8th rank before your opponent does the
same would win the game, most of the endgames you refer to would turn into a
king race. The pawns would lose their importance.
From: desj@ccr-p.ida.org (David desJardins)
Newsgroups: rec.games.abstract
Subject: Re: defects in abstract games
Date: 9 Jan 93 19:58:04 GMT
Organization: IDA Center for Communications Research, Princeton

Stephen L. writes:
> The no repeats rule can be used to create the ko situation and
> eliminate draws, or it can be used as a way to define a draw.  When
> is one preferable over the other?  Would Chess be 'improved' by
> eliminating draws?

Gwydden <kleber@husc11.harvard.edu> writes:
> Eeek!  By adding a no-repeat rule?  Say you get to a
> king-vs-king-and-bishop position, which is currently a draw, since
> there's no way for either side to give mate.  Then if you institute
> the no-repeat rule, you keep moving these three pieces around until
> one player cannot move without ending up in a previously-seen
> position, of which there are only about 112,000

Here's a slightly more plausible way to eliminate chess draws (at least,
ones due to insufficient material), while maintaining both playability
and the current spirit of the game.  Change the rule from

  (NOW) If neither player makes a pawn move or a capture in 50
        consecutive moves, the game is a draw.

  (NEW) If either player fails to make a pawn move or a capture in 50
        consecutive moves, that player immediately loses.

One consequence would be that in a position with true insufficient
material, such as king vs. king and bishop, the last player to make a
capture would win.

In general, there would be an added state in endgame positions which are
becoming drawish: the last player to capture/pawn-move would have the
advantage, and the other player would be forced to make progress to
avoid losing.

                                        David desJardins
From: nates@ll.mit.edu ( Nate Smith)
Newsgroups: rec.games.abstract
Subject: Re: defects in abstract games
Date: 6 Jan 93 20:41:17 GMT
Organization: MIT Lincoln Laboratory

In article <1993Jan6.054828.15197@cs.wisc.edu> mfrank@wilma.cs.wisc.edu (Matt Frank) writes:
>
>This whole discussion is begining to remind me of Godel's Theorem.  (i.e. any
>sufficiently powerful axiomatic system is inconsistent, or something like
>that.)  Given that no "perfect" mathematical set of rules exists, why should
>we expect that a "perfect" (i.e. non-trivial but completely consistent) set
>of game rules should exist?
>
>Come to think of it, one way to win in Nomic is to be unable to complete
>one's move (in essence, to find an inconsistency in the rules).
>
>-Matt

i like this line, that's a favorite book of mine, 4 feet away infact,
....we could state it as

 _Matt's_Theorem_:
+-------------------------------------------------------------------------+
| The system of rules for any non-trivial game, including purely abstract |
| games, must contain at least one defect.                                |
+-------------------------------------------------------------------------+

so, for example, my 5-in-a-row game on a hexgrid, with only 3 directions
to make the 5-in-a-row, must be "trivial", since the rules are but 2 and
are:
         1) each player takes turns placing a new stone of their
            color upon an unoccupied hexpoint.

         2) the game is ended and won by the first player to
            make 5-in-a-row in any of the 3 possible directions.

so even though i have no idea what the triviality is, i can take umbrage
in the Theorem that it must exist.  or...is there a defect in the rules?

the board size i've used is 10 on a side for 271 points, but 11 (331) is
probably safer to avoid the Defect of the finite board size.  what if
11 isnt safe?  infinite board, use a computer to pan over it....

ok - infinite board, no edge effects...is there a defect?  if not, does
that imply triviality?

what do you think of the Theorem?  boulderdash, right?  :-)

- nate
Newsgroups: rec.games.abstract
From: hoey@AIC.NRL.Navy.Mil (Dan Hoey)
Subject: Sprouts and Nim (was Re: defects in abstract games)
Organization: Naval Research Laboratory, Washington, DC
Date: Wed, 6 Jan 1993 23:43:48 GMT

kwhyte@arthur.uchicago.edu (Kevin Whyte) writes:

> ... The games which can be reduced to Nim
> (Sprouts can't, and hasn't been solved ....) are exactly
           ^^^^^
> those where 1) The game always terminates, even it the players don't
>                alternate moves.
>             2) From every position both players have exactly the same
>                legal moves, and exactly the same winning positions,
>                etc....

Sprouts has these features, and _can_ be reduced to Nim, at least with
in normal play (last player wins).  Misere Sprouts, where the last
player loses, has positions that aren't encountered in Nim, but they
can be dealt with using the extended Sprague-Grundy theory you can
find in On_Numbers_And_Games or Winning_Ways.

I suspect that ``can't'' is a misprint for ``can''.

Dan Hoey
Hoey@AIC.NRL.Navy.Mil
Newsgroups: rec.games.abstract
Subject: Mornington Crescent?
From: dnicol@vax1.umkc.edu
Date: 4 Jan 93 16:01:10 CST
Organization: University of Missouri - Kansas City
NNTP-Posting-Host: vax1.umkc.edu

What is Mornington Crescent?
Newsgroups: rec.games.abstract
From: wms@ssd.intel.com (William Shubert)
Subject: Re: defects in abstract games
Organization: Supercomputer Systems Division (SSD), Intel
Date: Wed, 6 Jan 1993 23:33:58 GMT

desj@ccr-p.ida.org (David desJardins) writes:
>Kevin Whyte <kwhyte@arthur.uchicago.edu> writes:
>> This is definitely not true.  The games which can be reduced to Nim
>> (Sprouts can't, and hasn't been solved ... another good game, but the
>> three lives per vertex is too arbitrary to call it perfect.)
>
>It doesn't seem very arbitrary to me.  It has to be greater than 2 (or
>else the game would be pointless) and less than 4 (so that the game
>terminates).  How many integers are there in that range?

   Ummm...the game DOES terminate with 4 provided that with a new point on a
line the two new lines must appear on opposite sides.  Sounds odd, but it
works as a game.  It's called "Brussell Sprouts" (sp?) and instead of points
crosses are used so a game goes like:

  +          +        +        +          +
             |        |        |          |
             +        +        +-X      /-+-X
             |        |        | |     +  | |
  +    +     +   +    +-+-+    +-+-+    \-+-+-+

etc. Note that at the "X" and the leftmost "+" only one new line can be drawn
because the other growth possibility has no point to connect to without
crossing a line.
   So, with some modifications it can be said that there are at least TWO
integers in that range.  I do agree, however, that calling Sprouts "imperfect"
because of the three rule is stupid; you could state with equal validity that
ANY game is imperfect since ALL games have limits of some sort.  Traxx, for
example, could be said to be arbitrary in it's restriction to two dimensions.
Or Nim could be called arbitrary in its two level hierarchy (piles of stones).
				-Bill (wms@ssd.intel.com)
Newsgroups: rec.games.abstract
From: bcannard@hppcb36.mentorg.com (The Human Mi-Go)
Subject: Re: defects in abstract games
Originator: bcannard@hppcb36
Date: Mon, 04 Jan 1993 17:33:21 GMT
Reply-To: bob_cannard@mentorg.com
Organization: Yuggoth Interstellar Travel Inc.
Keywords: 
Followup-To: 


In article <1993Jan2.065410.23378@risky.ecs.umass.edu>, trodrigu@spock.ecs.umass.edu (Tao R or Stephen L) writes:
...
|> Many people have referred to draws in my game SUSAN even though I have no
|> specific rule defining a draw.  I imaging the same same thing happens
|> with Abalone which also lacks a rule defining draws.  The no repeats rule
|> can be used to create the ko situation and eliminate draws, or it can be
|> used as a way to define a draw.  When is one preferable over the other?
|> Would Chess be 'improved' by eliminating draws?  Would Go be 'improved'
|> by adding them?  What makes these two cases so different?

Under British go rules (which may have changed since I crossed the pond)
draws are possible due to the 6-point komi - most countries use 5.5 points
to eliminate draws. Stalemate such as triple Ko is also possible (Japanese
ko rule is used); most tournaments treat this as a draw rather than a void
game due to time constraints. Draws don't happen very often but they're a
lot of fun when they do. IMO social and club games are improved by them, but
tournament games are better off without.

What makes the two cases different? In Chess repeating situations are much
less frequent than in Go, where they are so common that much of the tactical
and strategic play revolves around their resolution. If a repeating position
could lead to stalemate, it would be too easy to stalemate the game. Triple
Ko is too difficult to set up for this to be a significant problem.

Fighting for a points draw is not a serious strategy because it only takes
1 more point to win.
-- 
bob_cannard@mentorg.com			"More dynamite!" - Theron Marks
Newsgroups: rec.games.abstract
From: nicholso@pioneer.arc.nasa.gov (Melvin H. Nicholson YBH)
Subject: Re: defects in abstract games
Organization: NASA Ames Res. Ctr. Mtn Vw CA 94035
Date: Tue, 5 Jan 1993 23:29:06 GMT

In article <1993Jan5.190229.2264@ll.mit.edu> nates@ll.mit.edu ( Nate Smith) writes:
>In article <1993Jan2.065410.23378@risky.ecs.umass.edu> trodrigu@spock.ecs.umass.edu (Tao R or Stephen L) writes:
>
>in my opinion, you have hit upon what i think is the most undesirable
>aspect of chess.  the huge number of drawn games in proportion to the
>decisions is tiresome at best.  it is, however, a nasty problem to fix.
>so nasty it might be better off left alone.  in the recent fischer-
>spassky match, with the new fischer clock in place and with fischer
>known to hate draws, there were still 15 out of 30 games drawn - and
>that is a lower ratio...one of those karpov-kasparov matches had a
>huge number of draws due to the change fischer brought about by not
>having draws count for 1/2 points anymore.  it is the smallness of the
>board and the limitations on the piece's movements that creates a
>balance of power that makes it easier to defend, relatively, than to
>kill.  thus to reduce the draws, the game would need drastic alterations
>that may make it unrecognizable to its former incarnation.
>
>go would not be improved by a whole integer komi or perpetual check
>draw, again, in my opinion.  hey, this is another thing basketball
>has over hockey.  i just dont like draws in general.  others may
>disagree.
>
The draw-decision question has a tradeoff --- decisiveness of a victory.

Whereas hockey is prone to draws, basketball's large amount of scoring
degrades the signifigance of any particular score.  The same distinction
is even more pronounce in chess and go.  Go works in a huge number of
tiny gradations, whereas chess has a single, definative checkmate.

Which you prefer is entirely a matter of taste, and the suggestion that
these gradations somehow make go more "complex" or that a larger number
of moves in the search tree make the game more "challenging" are just
insulting.  On the latter point, not all moves are created equal, and the
equation of placing a stone in go to the move of a pawn in chess is 
asinine, or suggest the "search tree size" is a particular bonus sounds
rather like adolescent males worrying about how their penises "measure
up" more than anything worthy of interest.

Remember that rock-paper-scissors is more complex and challenging than
both go and chess in it's own way, and has a "search tree" of three.
Also there are games with an infinitely large search tree which are
quite simply trivial.

I hope that doesn't sound like a mad chessman defending his game.  The
only reason I limited my attack to go is that while the "Go is better
than chess" contigent has reared it's ugly head, the counterpart from
chess's fan club have been thus far silent (or absent at least).

Trying to justify game preference logically is a futile proposal, and we
can do without the psuedo-logic that comes from the attempt.

Mel
From: cet1@cus.cam.ac.uk (C.E. Thompson)
Newsgroups: rec.games.abstract
Subject: Re: defects in abstract games
Keywords: Hex
Date: 6 Jan 93 15:45:14 GMT
Organization: U of Cambridge, England

In article <1993Jan4.170439.4759@midway.uchicago.edu>, kwhyte@dent.uchicago.edu
(Kevin Whyte) writes:
|> 
|>   If you want a game without defects, try Hex.  For those
|> who don't know, Hex is played on a rhombus of hexagons (or,
|> for go players, the veritices of a triangular lattice).  One
|> player plays black stones, the other white.  Black tries to
|> connect the top and bottom edges of the board with a solid
|> line of black stones, and white tries to do the same from left
|> to right.  The game has no draws, no complicated rules, and
|> is difficult.  The biggest drawback is that the first move 
|> is a significant edge.

Indeed, a winning advantage (by strategy stealing) with perfect play.
Is it a "defect" that one knows what the result of the game should be
even if one cannot actually execute a strategy to achieve it? (Rather
than merely knowing that there must be some definite result of perfect
play, as in chess or go.)

Chris Thompson
JANET:    cet1@uk.ac.cam.phx
Internet: cet1@phx.cam.ac.uk
From: kwhyte@dent.uchicago.edu (Kevin Whyte)
Newsgroups: rec.games.abstract
Subject: Re: defects in abstract games
Date: 4 Jan 93 17:04:39 GMT
Organization: Dept. of Mathematics, U. of Chicago


  If you want a game without defects, try Hex.  For those
who don't know, Hex is played on a rhombus of hexagons (or,
for go players, the veritices of a triangular lattice).  One
player plays black stones, the other white.  Black tries to
connect the top and bottom edges of the board with a solid
line of black stones, and white tries to do the same from left
to right.  The game has no draws, no complicated rules, and
is difficult.  The biggest drawback is that the first move 
is a significant edge.  

 Kevin


We are faced with the very real possibility that "digital" and 
"manual" will be used as antonyms.
Newsgroups: rec.games.abstract
From: nates@ll.mit.edu ( Nate Smith)
Subject: Re: defects in abstract games
Organization: MIT Lincoln Laboratory
Date: Tue, 5 Jan 93 19:02:29 GMT

In article <1993Jan2.065410.23378@risky.ecs.umass.edu> trodrigu@spock.ecs.umass.edu (Tao R or Stephen L) writes:
>We could look at this idea of 'perfection' in abstract games as a form of
>mathematical elegance, or we could look at it in terms of real-world
>values such as ease of play, ease of learning, simplicity of manufacture,
>physical beauty of the game, etc. ...[]...

i think when it comes to this notion of defects in abstract games, we
should stick to abstract defects.  the real-world values are important,
although your "ease of play" and "ease of learning" kind of stray back
into the abstract realm.  if we think of Occam's Razor coming into the
picture, it might be that mathematical elegance and ease of play/learning
are linked.
>...[]...
>Would Chess be 'improved' by eliminating draws?  Would Go be 'improved'
>by adding them?  What makes these two cases so different?
> 
>- Stephen  (no answers tonight, just questions)

in my opinion, you have hit upon what i think is the most undesirable
aspect of chess.  the huge number of drawn games in proportion to the
decisions is tiresome at best.  it is, however, a nasty problem to fix.
so nasty it might be better off left alone.  in the recent fischer-
spassky match, with the new fischer clock in place and with fischer
known to hate draws, there were still 15 out of 30 games drawn - and
that is a lower ratio...one of those karpov-kasparov matches had a
huge number of draws due to the change fischer brought about by not
having draws count for 1/2 points anymore.  it is the smallness of the
board and the limitations on the piece's movements that creates a
balance of power that makes it easier to defend, relatively, than to
kill.  thus to reduce the draws, the game would need drastic alterations
that may make it unrecognizable to its former incarnation.

go would not be improved by a whole integer komi or perpetual check
draw, again, in my opinion.  hey, this is another thing basketball
has over hockey.  i just dont like draws in general.  others may
disagree.

- nate
From: desj@ccr-p.ida.org (David desJardins)
Newsgroups: rec.games.abstract
Subject: Re: defects in abstract games
Date: 6 Jan 93 22:34:17 GMT
Organization: IDA Center for Communications Research, Princeton

Kevin Whyte <kwhyte@arthur.uchicago.edu> writes:
> This is definitely not true.  The games which can be reduced to Nim
> (Sprouts can't, and hasn't been solved ... another good game, but the
> three lives per vertex is too arbitrary to call it perfect.)

It doesn't seem very arbitrary to me.  It has to be greater than 2 (or
else the game would be pointless) and less than 4 (so that the game
terminates).  How many integers are there in that range?

                                        David desJardins
Newsgroups: rec.games.abstract
From: trodrigu@spock.ecs.umass.edu (Tao R or Stephen L)
Subject: Re: defects in abstract games
Summary: Win or Draw?
Organization: University of Massachusetts, Amherst
Date: Sat, 9 Jan 1993 10:39:44 GMT

While thinking about draws in Chess, I've decided that I probably don't
like the strict form of the 'no repeats' rule in general.  The problem
is that forcing repetition becomes an aggressive strategy.  It seems to
me that this would diverge from the spirit of most games.  For example,
I think that Abalone would have the same basic problem with prohibiting
repetition that Chess would.  By contrast, prohibiting repetition in Go
creates one of the central elements of the game, so this objection does
not apply in the case of Go.  On the other hand, repetition leading to a
draw is more intuitive (in games other than Go) because it implies that
neither player has anything better to do.
 
- Stephen

Newsgroups: rec.games.abstract
From: umsmigi0@ccu.umanitoba.ca (Trevor Allan Smigiel)
Subject: Go (Rules please?)
Keywords: Go
Organization: University of Manitoba, Winnipeg, Canada
Date: Wed, 6 Jan 1993 15:31:40 GMT

Could somebody out there post the rules for go.  I am only
slightly familiar with them and would like a reference.

Also, is there a good place to by go stones and boards?  I
have looked locally and found a set with board, stones and
rules for $40(CAN).  It seemed like a low quality set, and
I would prefer something a little nicer.

Thanks,
Trevor
From: bruno@cerberus.csd.uwm.edu (Bruno Wolff III)
Newsgroups: rec.games.abstract
Subject: Re: defects in abstract games
Date: 7 Jan 1993 00:00:44 GMT
Organization: University of Wisconsin - Milwaukee
Reply-To: bruno@cerberus.csd.uwm.edu
NNTP-Posting-Host: 129.89.7.46
Originator: bruno@cerberus.csd.uwm.edu

From article <1993Jan6.174837.15285@midway.uchicago.edu>, by kwhyte@arthur.uchicago.edu (Kevin Whyte):
] In article <1993Jan6.085328.28673@risky.ecs.umass.edu> trodrigu@spock.ecs.umass.edu (Tao R or Stephen L) writes:
]
]   This is definitely not true.  The games which can be reduced to Nim
] (Sprouts can't, and hasn't been solved ... another good game, but the
] three lives per vertex is too arbitrary to call it perfect.) are exactly
] those where 1) The game always terminates, even it the players don't
]                alternate moves.
]             2) From every position both players have exactly the same
]                legal moves, and exactly the same winning podsitions,
]                etc.  This is not true for games like Hex, Twixt, Traxx,
]                or Go, since which color you are makes a difference.
] 
Sprouts does statisfy the conditions for reducing to Nim. However that isn't
a lot of help since sprouts positions tend to get more complicated rather
than splitting into subgames which would make the nim analysis useful.