chess-The Oxford Companion to Chess - First Edition by David Hooper & Kenneth Whyld

74 COMPU1IRS AND CHESS
@mpuler now exisling had been calculaling with
out duplication a1 millions of ope.ations a secood
sincc the earth solidified the iask would hardly
have been begun. The nore moves the conputer
can examine in this liee sedch the belter, bu1
ultinately each terminal posilior has to bc assessed
and anything oih.r than a maie or decisive gain oI
malerhl involves utrertainly. The second
approacb is lo use as far as possible a librdy oI
slored inlomation. Comon opening noves can
he called loBard without calolation. ard the
same is possibl. if a slan.lard e.dgame n reached.
The third melhod is to seet pattems or fearues in :r
position so that sone kind of stralegical judgeme.l
nay be applied. ftograms.an be made to 6ses
the effectivene$ of their own nethods and to vart
then osn cnreria, perhaps leaming to play ches
betrer than the per$n *ho trro1e the progran.
These are aspecis ol great importance for the
research oI artilicial inteUigence. Contrary to
popular helici a gra.dmaster does .oi often
calculare much turrher ahead ihan ordinary players
doj his greater playirg srength stens frcm a quick
appreciation olihc coherence a.d significa.ce ofa
positiotr. As yel no-one kno*s qhar iniuirive
reactions de tomedinthatinslantof recogrition.
ln l958acomputerplayedchesscodeclly. i.e. in
,...rdrn.e vfuh rhe l:m t'nr the nnt senons
program cahe in 1966 shen Mac Hack became
opemrional in the USA. The lollowing year it
played. unsuc@ssfully, in an ordinary tonrnament
and at about rhe same time contests beSan to be
held betNeen ompute$. The fistonputerNorld
chanpionship was heid at Stockholm in l9?4 sncn
13 programs frcm eighl count.ies iook pa!t. Tbe
winner, Kaissa, was from the USSR. Ihe second
chanpioDship, Toronto 1977, and the third, Linz
1980, pere son by American progiams. Thcsc
conlests are primarily scientiic meetings.
In 1976 the 6rst ches playine conputes ior
popular use cane on the narket and vilhi. nve
year there was an abundant supply oI machincs
capable of giving a good game lo all but tbe besi
playeE. There is no connercial incendle to rane
the playing stength of these computeB becausc
this world hardly cnlarge the polential market.
Imp.ovenents are aimed at increased lacilides
such asmoving thepiecesautonatically,oratpnce
.educdon. These machines all use STANDARD
NorarroN thus speeding the denise of lhe once
poPular DEs.RmvE NorAnoN.
Besides providing anusement or lraining lacililies
there are olher says in which conpuier can
hc.enl chess. TIEy can be used 10 check the
soundness oI problems, and here tne brutc lorce'
nethod is essertiali every possible series oI moves
within rhe limil specified in any dnect nare
problen nust be exanined. Solutions ol sludies
and tbe play in classical games nay be reexamined.
Archives can be kept to mainlain gane
scores or .esults or 10 check Foblems or studies tor
atrticipatio!. Adhinishalive tasks such as rakng
draws tor swss sysmM lourname.ts or ensunng
the accuracy ot lypc{ctting for printe( can bc
carricd out by compnter.
ln rhis position from lhe second computer Norld
chanpionshiplheprogamforBlackplayedS,l. . .
Res. Five hundred spectatoB includinc many
masteis wondered what had gone vrong wirh the
program. Subscqueni testing revealed that tbe
compuler had rcjecred 34 . . Kg7 because oi rhe
Iorced nate in 6re: 35QE+ KxI8 368h6+ Kg8
(o' 36...B97) 3?Rca+Qd8 38Rxd8+Re8 39
Rxe8. This exampte iluslraies lwo points: fi6t,
compuleE nay 6nd brilliancies overlooked by
expert playersi second, any exPert who h.d seed
the male would still have played 34 ... Kg7,
hoping the opponcnt mighi olcrlook thc quccn
sacri6ce.because34...Re8offered.ohope.Tbe
conputer always assunes thar lhe opponenl will
play the best nove. For exa6ple, in an even
positio^ acomputcrmighl considcr making a pawn
sacrifice that led to a clear advantage i. ten
vanalions but vould rejecr this sacnlce it one
extrerely obscure varialion ted to disadvanlage. A
human, however, night think il Ras worth a paw.
to make the opponeni Nalk a tightrope
A project in-easingly being tactled is that ot
nndine the besr play from any position (an oprimal
data base) rorcedain BAsc ENDCAMES.In 1975 an
A ificial Intelligence unn ol a. insritute in MatoF
ca eslablished lhe 22,i100 posirions r+R v. r,
White 10 play. The program Nd developed iro6 a
Second World War te.nniqE for detccti.g submannes.
In 1977 Arlazarov and Ftrter, in Moscow,
elanined lhe ending K+ Q+P !. K+Q andstored
the nore than 100 million positions on nine
magnetic tapcs. Playing in Vit.iLs BRoNSr.rN
reached such an ending and alteradjoumnent he
telephoned rhe progrannes in Mosco{ They
searchcd thc data base lor thc rclcvant cxamples,
printed lhem, and put tbem on the nighr train ro
Vilnius. Arlazarov also conpleted a data base for
(+R+Pv. (+R. Strdhl.in andzagler. Germany,
published then data bases Io. K+Rv. K K+Rv.
K+B in 1978.
Thompson ol Anerica pu1 the approrinately
two million positions K+Ov. K+RWhitc to play
and aboul the same nnnbe. Black to play on afle.
They sho*ed th.t no winning line of play needed
more than 31 6oves. Both BERLTNER. whose
do.toral thesis was on .ompltcr chess. aod