IQ and Chess Strength
The following is taken from Jonathan Levitt's Genius of Chess and from an article by Bill Wall on IQ and Chess, poured into a blender to create my delicious lesson smoothie. These excerpts include some interesting anecdotes and case studies of IQ in relation to chess abilities.
players discuss IQ
Back in 1988, there was an impressive chess festival in the small industrial town of St. John's, Canada. Two large and very strong Open tournaments were combined with the complete set of seven Candidates' matches in the World Championship cycle of the time. The English contingent were all on good terms and in good cheer (Nigel Short was making mincemeat of Sax in his match, likewise Jon Speelman of Seirawan) and usually formed, combined with certain selected 'foreigners' (like Spassky), a massive eating party which the local restaurants struggled to accommodate.
have a fair recall of the conversation on one such evening. Nigel
Short was asked what he thought his IQ was. He was not sure, but
(far too modestly) proposed 130 or 140. John Nunn,
his second, suggested that with a little training, Nigel could
knock his score up to at least 160. Speelman was not impressed by
IQ tests generally, and everybody saw the inadequacy of any test
which depended on how much practice you had had at the type of
At this point, some bright spark (me) suggested that it might be a better measure of intelligence to do two tests and see how much the person improved. Quick as a flash, Nigel replied that this was a very bad idea since you could do deliberately badly in the first test! It took me a few seconds to grasp his meaning - that you could artificially inflate the difference in your scores and thus score better in the proposed test.
Everybody was fairly impressed by this quick and crafty answer and the conversation moved on. The story illustrates something important about the nature of the chess mind - how good it is at short cuts (no pun intended) and tricky ways round things. Mathematicians are usually less devious in their thinking - it is important to find direct ways to prove things.
The mathematician's approach to getting what you want
There is a story about a Turkish reformer who wanted to discourage women from wearing the veil. Instead of attempting to forbid it directly (the mathematician's approach), he issued a decree that all prostitutes must wear veils. This indirect 'trick' proved the workable, effective way to his objective and shows the sort of thinking which chessplayers are often rather good at.
In chess too,
it is the result that counts, not how correctly it is derived.
'Players' like to try things out, and not to study other people's
work diligently. Chessplayers are good thinkers but not always good
students, as many university dons have found to their
How strong is
the connection between chess ability and IQ?
I discussed what is meant by intelligence at the start of the book (just after the introduction), and later gave it as a typical characteristic of the chess genius, but so far I have not really answered the question: 'how strong is the connection between chess ability and IQ?'. There are many reasons, some of them simply common sense, to believe that the two are strongly correlated. (A correlation of zero means that two things are entirely independent; a correlation of one means they are entirely related or dependent on one another. Mathematically speaking, all things are correlated somewhere between zero and one.) De Groot considered several of these reasons, and the next paragraph summarises some of his conclusions.
So wait…is there a correlation between IQ and chess strength?Spatial intelligence is crucial for chess thinking. It's the ability to "perceive possibilities". This is important because you not only need to know what (a system of knowledge) but also know how (the system of experience).
This system must be stored (memory) and well managed - rules, analogies and operating principles must be constantly abstracted, adapted and improved (perhaps not always on a conscious level). Chess thinking often involves a complex, hierarchical structure of problems and sub-problems, and the capacity for retaining such complex structures of data (not getting confused), and for keeping objectives clear and well organised, all correlate with having a high IQ.
offering, very tentatively, my equation linking potential chess
strength with IQ, I would like to say a little more about the IQ
scale. Assuming, somewhat incorrectly as pointed out earlier (and
it is true that from a false assumption you can deduce anything,
but this sort of false assumption should be seen as just an
inaccurate approximation), that intelligence follows the 'normal'
distribution (mean 100, standard deviation 15), then how many
really bright people would there be? The mathematical/statistical
implications would be as follows:
16% above 115;
2.3% above 130;
0.13% above 145
0.003% above 160
This would mean only .003 percent of the population would have an IQ of over 160. This would correspond to approximately the following numbers of people above the given levels in England:
1,150,000 above 130;
65,000 above 145
1500 above 160.
Now that you have an idea of IQ and its distribution throughout a typical population, let's get to the good stuff - case studies of chess and its link to genius and intelligence.
Some say that the highest IQ ever possess by a human adult was Leonardo da Vinci, with an IQ of 220. Obviously, he lived before the development of IQ tests - so we can't say for sure.
Hippolyte Taine (1828-1893) stated that playing
several games of blindfold chess was an achievement in visual
memory and high intelligence. Taine asked a chessplayer how he
understood imagination and images, and how he played blindfold
chess. Taine believed that the type of imagery used in chess was an
"internal mirror" that reflected the precise state of the things
In 1893, Alfred Binet (1857-1911) made a study of the connection between mathematics and chess. After questioning a large number of leading chess players, he found that over 90 percent of them were good mental calculators and had good memories. On the other hand, he found that some mathematicians played chess, but few were strong players.
In 1894, Alfred Binet conducted one of the first psychological studies into chess. He investigated the cognitive facilities of chess masters. Binet hypothosized that chess depends upon the phenomenological qualities of visual memory. He found that only chess masters were able to play chess successfully without seeing the board and intermediate players found it impossible to play a game of blindfold chess.
In 1925, three Soviet psychologists, Djakow, Rudik, and Petrovsky, conducted extensive tests on chess masters and came to the conclusion that their powers of memory were only greater than that of the layman as far as chess was concerned. In other areas, there was no difference. The researchers determined that high achievement in chess is based on: exceptional visual memory, combinational power, speed of calculation, power of concentration, and logical thinking.
In 1942, Leta
Hollingsworth studied children with IQs of 180 or more. Included
was a chess player who became nationally ranked (source not named).
She found out that early talking and reading was what most
differentiated these children from the average. She observed that
high IQ children failed to develop desirable work habits in
a school setting geared for average children. In such a
setting, the high IQ children spent considerable time in idleness
and daydreaming. Consequently, they learned to dislike school. She
also noted that high IQ children found it difficult in finding
companionship. Consequently, these high IQ children became
socially isolated. Hollingsworth believed that
high IQ children need to be educated for leisure and recommended
that high IQ children play chess since it could be enjoyed by
people of all ages and could potentially assist these children in
bridging social gaps.
In a 1977-79
study by Dr. Yee Wang Fung in Hong Kong, chessplayers showed a 15
percent improvement in math and science test scores.
Some sources give Garry Kasparov, a renowned chess player, an IQ between 185 and 190. But in 1987-88, the German magazine Der Spiegel went to considerable effort and expense to find out Kasparov's IQ. Under the supervision of an international team of psychologists, Kasparov was given a large battery of tests designed to measure his memory, spatial ability, and abstract reasoning. They measured his IQ as 135 and his memory as one of the very best.