Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: Congratulations to Rebel Century

Author: Ricardo Gibert

Date: 10:54:55 10/04/99

Go up one level in this thread


On October 04, 1999 at 13:07:51, Robert Hyatt wrote:

>On October 04, 1999 at 11:43:47, Ricardo Gibert wrote:
>
>>
>>But what about the example of a drawing sac? Why leave that one out?
>>Technically, mate (mate is really misnomer) is a "forced concession of the
>>battle", you don't actually kill the king. That's why we have a complicated
>>mating rule. It would be simpler to just capture the K, but the inventers wanted
>>to keep the game "polite" and leave the really _fun_ part out. Perhaps, because
>>the game was actually anticipated to be played by real kings, they decided it
>>was "wiser" to leave the last grisly detail out. Killing a king is not really
>>fun when a _real_ king can really kill you in return. But this not _my_ reason
>>for calling it a sac. It is a sac when I give something up and I don't collect
>>the material back, either because of mate or a forced draw or whatever (=your
>>version?). Being "prevented" from getting the material back, because an opponent
>>resigns or draw is agreed, does not count of course.
>>
>
>I didn't leave the draw option out.  It is _identical_ to the mate situation.
>A program plays a move, and discovers that it can checkmate you no matter what
>you can do.  Is that a sac?

It is if material was given up to do so.


 A program is behind (losing to you) and discovers
>that if it makes a move it can force a repetition no matter what you can do.  Is
>that move a sac?

It is if material was given up to do so.


Or is it suddenly unimportant since it starts a forced
>combination that ends the game forcefully, whether winning or drawing?
>
>That is the ambiguity I don't like in the general use of the word "sac".
>"sacrifice" means to give up something.  I am not giving up something if I
>mate you in the process... I am getting back more than I gave up many times
>over.

Of course you are getting back. That's the point of the sac. Why sac if you
don't get a net gain?


Ditto for drawing if I am in a losing position...
>


What is given up is _material_. What you don't get back is the _material_. What
you get back is something else. That's a sac to put it simply. When get nothing
or too little back, it is not a sac, it is a blunder.

>
>
>>
>>By my way of looking at things, a mating combination may or may not include a
>>sac. I prefer to keep the distinction, rather than meld them together as you do.
>>People enjoy the sac version of a combo more. Reason enough to keep the
>>distinction IMHO.
>
>Doesn't bother me...  if we agree that the definition of a 'sacrifice' is to
>give up material at some point, whether you get it back or not...  The only
>problem with that definition is that in computer games (particularly those
>against humans) it happens so often that it becomes a bland happening.  I see
>such 'sacrifices' (combinations) in most every game against a human played at
>blitz time controls...
>
>
>>Definitions are fairly arbitrary. I choose an objective
>>definition that can be applied by anyone. You choose one that is subjective.
>>Taking the Rebel game as an example. If a 1200 played that "sac" it would be a
>>true sac, since he cannot reasonably be expected to calculate all the
>>ramifications. If a GM plays the sac, maybe it is a sac or not, depending on the
>>player, time situation, etc. A GM could calculate it to the point where he gets
>>the material back or play it based on intuition. I don't care for this
>>ambiguity.
>>
>
>
>Not a problem for me either way.  If the word must stay totally ambiguous,
>I can live with it...  But a sac from a GM and a sac from a program are two
>totally different concepts.  Because a program will _never_ do it 'just because
>it feels right' while a GM will do it regularly for that reason, without being
>able to calculate all the repercussions...

A program will do it as a gamble. You clipped an important part of my post that
addressed this. What gives?



This page took 0 seconds to execute

Last modified: Thu, 15 Apr 21 08:11:13 -0700

Current Computer Chess Club Forums at Talkchess. This site by Sean Mintz.