Re: computer-go: Evaluating positions

[Heikki Levanto <heikki@xxxxxx>]

On Thu, Jun 21, 2001 at 02:49:25PM -0400, Don Dailey wrote:
> I  used the term ownership  in order to get the  idea  across that the
> player on the move may have the "option to own"  it.  But I think this
> was a poor choice of  terminolgy.  I need a term  that means "right of
> first choice."   This right alternates  on  each move because  you can
> only claim so much on one turn, then the other guys turn.

Yes, indeed! Not only the "right of first choice", but a numerical estimate
on the size of the right! In most games, if black has played at the 4-4
point, white has the "option to own" the corner. Often he should not use
theoption, because the cost of doing so would be to high...

 
>    Interesting speculation, but I fear it is more relevant to the mathematical
>    game of go than to the game we like to play in practice. 
> 
> We are bound completely by the mathematical game, I don't see how you can
> distiguish the two.

"The difference between theory and practice is that in theory there is no
difference between theory and practice" ;-)

Yes, we are bound by the mathematical game, but only as long as we have a
figting chance to consider the mathematical theories before we have to make
a move! In real life we are bound by the clock, or by the impatience of
ourselves or our opponents, and have to make a move before we have any
"mathematical" reason to choose one move before the next. This is exactly
where the mathematical way of thinking falls short of real-life playing...


[...]
> I have attempted to define a few terms  that are mathematically sound,
> but I know in practice we cannot  easily apply these definitions, it's
> beyond our power in most cases.  However,  I don't think that it hurts
> to keep them in mind.  Good players aspire  to play the "best move" as
> often as possible, even though they cannot always  do this.  But it is
> not wrong for them to be aware that one or more best moves exist.

I agree very much! As you say, the problem is that " in practice we cannot
easily apply these definitions". That is what makes the game worth playing!

* * *

> It's the same  with "beauty."  Did you ever  play a beautiful game?  I
> have played  beautiful  chess on  very rare occasions,   but I have no
> formal method of "proving" this!  And yet I would never throw away the
> concept of beauty, I still think it is a real thing.

I think you are underestimating the value of "beauty"! I belive I have
played beautiful Go on rare occasions, but the mathematical theory of go has
been insufficient to capture that beauty. I feel the problem has been more
in the theory than in my game, because - at the time, and in the
circumstances - I played the best moves...  Not mathematically best, but the
best I could come up with, and know that even if I had had the time and the
resources to analyze the situation much more, I would still have chosen the
same moves.  If some professional player (or a hypothetical god) would have
chosen a different move is of course relevant, but not to my experience of
the game... 

This is *my* approximation of "perfect play". As long as we can not reach
the absolutely perfect play (not with todays computers, or tomorrows!), we
have make do with approximations...
 
> I wonder  if that operation where they  took out the  right side of my
> brain has anything to do with my viewpoints here?

Quite possibly, but I shall not comment on that now ;-)



-- 
Heikki Levanto  LSD - Levanto Software Development   <heikki@xxxxxxxxxxxxxxxxx>