Fight that’s best of three
QUESTION A ‘truel’ is a duel between three. Has such an event ever taken place?
The Truel — or a three-way duel — was used to dramatic effect in the climactic scene of Sergio Leone’s spaghetti western The Good, The Bad And The Ugly and has featured in other films, including Pirates Of The Caribbean: Dead Man’s Chest and Reservoir Dogs.
The word was coined in Martin Shubik’s 1954 book Readings In Game Theory And Political Behaviour.
Game theory is the science of strategy. It attempts to determine mathematically and logically the actions that players should take to secure the best outcome in a variety of games.
It can be used to study group dynamics in economics and psychology.
The following problem is an example of how it works. Tom, Dick and harry fight a truel with the following rules:
a) The order of the shooting is determined randomly.
b) They continue firing at each other in this order until only one is alive.
c) All shots that hit another person are lethal. everyone knows Tom scores 100 per cent of all shots, making him the most skilful shooter, Dick scores 80 per cent and harry scores 50 per cent, which means he is the worst shot.
d) each person has the option of missing intentionally.
The question is, would you rather be Tom, Dick or harry?
Unlike a duel, where the most skilful shooter is the likely victor, in a truel, harry, the worst shot, has the best chance of survival. This is true regardless of the shooting order.
harry should let Tom and Dick — who know they are more of a threat to each other — take part in the first bout. This means he would end up with the first shot in the two-person face-off.
But if harry is the first shooter, he should deliberately miss because he does not want to risk killing Tom or Dick, since that would make him the second shot in the subsequent duel. Alan B. Coleman, Peterborough, Cambs.
QUESTION Is it true that Timbuktu once had a population of around one million people?
The phrase ‘from here to Timbuktu’ has become synonymous with mysterious isolation — the farthest you can travel.
however, for centuries, this city in Mali, a landlocked country in West Africa, was a major trading hub and a centre for scholarship. Its fortunes have risen and fallen over the centuries, but it is doubtful that its population was ever one million.
Timbuktu was founded in AD1100 as a seasonal outpost for Tuareg nomads. In the late 13th or early 14th century, it was incorporated into the Mali empire and became a flourishing centre for the transSaharan gold and salt trade.
The city’s wealth came to the world’s attention in 1324 when the Muslim ruler of Mali, Sultan Mansa Musa (1280-1337), made an extravagant pilgrimage to Mecca with 60,000 others.
It is said that he brought (and spent) so much gold that the trading price plummeted and took a decade to recover.
This put Mali on the map: a Spanish chart of 1375 shows Mansa Musa bearing a large gold nugget.
Around 1327, the Sankore University was established in Timbuktu. Its legendary status has led to wild population estimates of anywhere between 100,000 and one million.
But in his history Of West Africa (1850), Malian historian Sekene Mody Cissoko estimated the population peaked at around 75,000 in 1450. elias N. Saad, in Social history Of Timbuktu (1983), believed it to be closer to 50,000, which was close to the population of London at that time.
In 1468, Sonni Ali conquered Timbuktu and put to death many scholars. This began a decline for the city, which at one stage had fewer than 20,000 inhabitants, though today there are 50,000 once more.
A. Delain, London EC2.
QUESTION How do blind Americans differentiate between U.S. bank notes, which are all the same size?
AMONG world currencies, U.S. bank notes are almost uniquely uniform in terms of size, weight and texture. That makes them nearly indistinguishable to the touch.
The standard method for blind people to distinguish currency is to fold it in a particular way. Typically, a $1 bill is left unfolded, a $5 bill is folded crosswise, a $10 bill is folded lengthwise and a $20 bill folded lengthwise and then by width.
however, this depends on sighted people telling them the money they are about to fold.
Technology has made the task easier, with phone apps that can identify bills and a free iBill handheld scanner which will read out the value of any notes you insert into it.
In the UK, bank notes vary in size and the new £10 note also has tactile features similar to braille.
Jean French, Luton, Beds.
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