4.5 Completeness of Area Rules III
In area rules it is extremely natural to be aware of the point at which
sente no longer has any value and indicate by passing that this point
has been reached. Even in area rules I and II, in actual play the game
can end by agreement at this point and the players can immediately
proceed to count the score. Applying a half-point correction at this
point for the asymmetry that arises from Black's playing first in the
game may seem unnatural, but it turns out to be extremely logical.
I proposed territory rules I in order to have a set of rules that counts
territory and prisoners. Since we have proved that territory rules I are
theoretically equivalent to area rules III, which recognize the last
competitive move as occurring immediately before the first pass, there
is no need to argue about the differences between territory rules I and
area rules III. Although they are formulated in very dissimilar ways,
which might be expected to lead to large differences in actual play, it
can be verified that no differences exist.
I would like to recommend territory rules I to those who are accustomed
to counting territory minus prisoners, and area rules III to those
who are accustomed to counting territory plus stones. Then go can be
played both ways under essentially the same rules, which will be a great
convenience, and there will be no rules problems.
Area rules III are shown in Part I. They have the same definitions (1)
to (5) as area rules I and II, and rules 1 to 5 and 8 apply without
change. The only difference is rule 6 (end of the game) and rule 7