Has chess got anything to do with war?
From ancient India to the computer age, the military has used chess as both a metaphor and even as training for warfare. But as Dominic Lawson writes, generals who compare themselves with grandmasters are exaggerating their control of human combat.
There is nothing more dangerous - or deafening - than warfare. And there are few pursuits that are as safe and as quiet as chess.
Yet chess began in 6th Century India as a 64-square board game, called Chaturanga, precisely modelled on the military forces of the day. There were "elephants", "chariots" and "'infantrymen".
And the most naturally gifted chess player in history, the Cuban prodigy Jose Capablanca, was the son of a cavalry lieutenant, and said he had been captivated at the age of four by the military symbolism of the little pieces as he watched his father play.
So it seems fitting that one of my guests on the third series of Across the Board - in which I have interviewed eminent chess enthusiasts and the odd world champion while playing a game against them - is the military historian Antony Beevor.
Beevor's books on the World War Two battles of Stalingrad and Berlin have sold in their millions across the globe, but his first career was as a British army cavalry regiment officer. And since he is also a passionately keen chess player, I was intrigued to know if he thought that great generals were like chess grandmasters - brilliant strategists of iron logic.
"Generals would love that parallel and they tend to see themselves in that way. But the truth is very far from that," says Beevor. His point is that battle is indescribably chaotic, with luck and chance playing a large role in any outcome.
And he makes an additional point: "In modern warfare the idea of total victory is now almost irrelevant. You've won - and then you lose the victory in a short space of time. Look at Iraq."
In fact, the military architect of the Iraq invasion of 2003, the former US Defense Secretary Donald Rumsfeld inadvertently touched on the difference between chess and real military action, when he talked about "known unknowns" in armed conflict.
Chess is what is termed a "perfect information" game - each player can see on the board everything there is to know about his opponent's dispositions.
This, perhaps, is why German military officers in the 19th Century devised a peculiar board game known as Kriegspiel - or "wargame" - as a training tool. It was later adapted into a variant of chess in which three boards are used, with neither player seeing the opponent's board or pieces, and the third board controlled by an umpire who executes the moves called out by each combatant.
But in the modern age, it is in the field of computer programs that chess - of the conventional sort - has captivated some minds in the military establishment. In the final year of the Cold War, 1989, I investigated this, having discovered that Prof Donald Michie, then the leading British authority on chess artificial intelligence, was being funded in his work by the US Army Research Institute.
Michie was the chief scientist at the Turing Institute at Glasgow. Turing, now most famous as the man who helped break the Nazis' Enigma code at Bletchley Park, was accompanied in that work not just by Michie but by almost the entire English chess team. The best British chess player of the day, Hugh Alexander, went on to become head of cryptoanalysis at GCHQ, while doubling as the Spectator's chess columnist under the pseudonym Philidor.
Michie, who died in 2007, said that his "two bishops versus knight" chess tutorial machine had "enormous" military application. I then discovered that the Deep Thought chess computer program - which in a later version called Deep Blue sensationally beat the reigning human world champion Gary Kasparov in 1997 - was being partially funded by Darpa, the Pentagon's Defense Advanced Research Projects Agency.
Back in 1989, Lt Col Robert Simpson, Darpa's head of expert systems research, told me that the Deep Thought chess program had a clear military application with "navigation in a battlefield situation. A machine like this, programmed with knowledge of the terrain a pilot is flying through, can digitise all the various route choices, explore them, and choose the optimum route. That is exactly what Deep Thought is doing."
It is fair to say that the computer programmers themselves, whose motives were solely to create world-beating chess algorithms, thought this was hokum. Ken Thompson, of Bell Labs and creator of the Belle chess program, observed: "The only military application for a chess machine like Deep Thought is to drop it from an airplane to kill someone."
On the other hand, it is interesting that in 2007 Darpa named its project to develop a super-intelligent battle computer system Deep Green - apparently in homage to the Deep Blue program which beat Kasparov in what, apart from Bobby Fischer's match against Boris Spassky in 1972, must be counted the most famous chess match in history.
That 1972 match in Reykjavik highlighted as nothing else the role of chess in a different sort of conflict - the Cold War. For the Soviet Union, supremacy at the chess board was a demonstration - as its rulers saw it - of the superiority of their socialist system over the Western capitalist one. After all, isn't chess supposed to be "the touchstone of the intellect"?
The strategic significance of this apparently individual battle between a single American and a single Russian was only emphasised further by the intervention of the then National Security Adviser Henry Kissinger, who personally called Fischer to persuade him not to abandon the match (as the eccentric grandmaster was threatening to do).
This, however, is chess as a metaphor for military conflict - which, as Beevor says, is infinitely messier than the calculations over the 64 squares.
Still, when I asked the military historian who he thought was the most skilful of all generals, he named Napoleon. The Corsican's successful campaigns had the speed of attack and concentration of maximum force on the opponent's weakest spot which we associate with the best chess players.
And "le petit general" was in fact a very enthusiastic chess player - especially in exile on St Helena, when he no longer had an army at his disposal. And no-one got killed.
More from The Magazine
Conquering a human at chess was a massive target for many artificial intelligence researchers in the years after WW2. It proved to be easier than they imagined.
Dominic Lawson is president of the English Chess Federation.
Across the Board is broadcast from 4-8 May on BBC Radio 4 between 12:04-12.15 BST. Antony Beevor's episode is on 7 May.
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