p.ix The programs of the future will not only be stronger than those
of today, but more interesting as concepts advance. Their development is going to be an interesting story, and it will be
fascinating to watch it unfold.
p.86 The savings achieved by the alpha-beta algorithm are enormous if the ordering of the moves is good.
p.90 The author's personal (and debatable) opinion is that the real criterion for judging whether
a program may be said to be playing chess in the same manner as humans do, is whether it follows processes equivalent to those
used by human players... The essential characteristics of human chess play involve comprehending the game as a continuous
sequence of real and possible positions interrelated by real and possible moves. Human chess players continually examine positions
to try to ascertain the essential characteristics, which are used to set goals for their play, and in trying to achieve these
goals, formulate plans... No program has yet [1984] demonstrated much more than rudimentary capabilities in these areas, and
it is fair to say that, according to this viewpoint, none of them is yet playing chess in quite the same manner as a human
does.
p.92 computer chess programs - at least those yet developed - know little about why they decided on their
last move; nor do they (with few and minor exceptions) form plans, set goals, or credit the opponent with forming plans and
setting goals. Every position is in effect a new game, and the requirement is to maximize a number representing a position
score, not to achieve an objective dictated by the position.
The [computer] program may not know what an objective is, let alone how to achieve
one... As a result, computer play is opportunistic, inconsistent, planless, and usually materialistic to the nth degree.
p.93 The reason for this emphasis on material is that computer programs cannot be trusted with determining
whether a positional consideration (e.g. an attack) is worth a material sacrifice... In general, however, chess programs
cannot judge whether positional factors compensate for material disadvantage, and so material factors and positional factors
are scored separately, with material deliberately made dominant to prevent sacrifices played at random.
p.95,106-107 It is very unlikely that any program that attempts to follow the human approach to
chess-playing will be able to cope with the best programs of the present type for quite some time after its introduction,
if ever... early efforts with the new concepts that are needed will probably involve a significant decline in playing
strength from present fixed-heuristic levels.
p.96 During the middlegame, computers play opportunistically and without any plan other than to maximize
the material and positional score at each turn. Often this involves shifting from one expected sequence of moves to something
completely different at the next turn, without any reason discernible to the human mind. The total planlessness and
lack of any aim or goal in computer play means that even the best machines are surprisingly vulnerable to long-range strategy...
Most programs have very little ability to conduct a positional attack when no obvious weak point exists... As compensation
for their lack of long-range planning and positional judgment, chess programs - even the commercial microcomputers - are sharp
tactically.
