Back in 1988, there was an impressive chess festival in the small industrial town of Saint John, 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 (Karpov was to join the seven winners). 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. I 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 questions involved.

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.

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 annoyance!

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.

Spatial intelligence - especially the ability to perceive possibilities for movement - is clearly crucial to chess thinking, as is the capacity to build up a system of knowledge (knowing that) and experience (knowing how). 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.

Before 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 and 0.003% above 160.

This would correspond to there being approximately the following numbers of people above the given levels in England:

1,150,000 above 130; 65,000 above 145 and 1500 above 160.

This should give you a fair idea of the way the normal distribution works, though remember that these are underestimates of the actual numbers. It is very difficult to generalise about the type of characteristics people have at different levels of intelligence. The following attempt to do so, an excerpt from Choice Mathematics (book one) by Kevin of the Teachers, is certainly quite provocative: There appears to be a hierarchy of abilities and traits in those of high intelligence as follows, suggesting an order for teaching intelligence.

IQ (S.D. = 15) Attributes 185 High natural neuro-kinesthetic control; high curiosity drive; anti trivia; in a hurry 180 New creation 175 Knows intelligent (and right!) 165 Formalisation; beginnings of self confidence; less hiding 160 Interest in logic; paranoia; minor creation; recognises good work; art; music 150 Trivial formalisation 145 Below this level and often above is everywhere found a slavery to conditioning





If this is true, then I guess all us slaves to our conditioning had better hope that the conditioning is good conditioning! Now that the vast majority of readers are feeling suitably outraged, it is time to present the Levitt Equation. I stress that this equation is subject to a number of reservations and should not be taken too seriously.