Author: Robert Hyatt
Date: 15:22:29 10/04/99
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On October 04, 1999 at 13:54:55, Ricardo Gibert wrote: >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. > >> that definitely isn't true. I have seen _many_ gm players make what they call a positional sacrifice... they allow their pawns to get ripped for what they hope is a compensating long-term weakness in the opponent's position that they can exploit _first_. So you can sacrifice material or positional considerations, and you can find combinations that win material or positional compensation for your side... the term is _still_ way too fuzzy, IMHO. Because sacrifice means to give up something you consider valuable. Not trade it for something even _more_ valuable... IE the "ultimate sacrifice" where soldiers give up their lives for no gain that they will ever realize... they do it for reasons that they consider more important than living themselves... >> >>> >>>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? Programs do _not_ gamble. They search a finite tree. They choose the path that leads to the best score within that tree. No way can that be considered 'gambling'... If you want to say that some evaluation terms are 'speculative' I would agree. But even then the program isn't gambling at all. The programmer is by having such a term...
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