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Greetings, Speaking of books... Gelfer's excellent Positional Chess Handbook has a chapter on them - as it does on virtually everything else! Perhaps a list of game positions which he features will allow you to find them in a database/book!? Skold-Keres. Stockholm 1966/67 D. Bernstein-Murey, Israel 1980 Gelfer-Ein Dor, Israel 1980 Spassky-Gheorghiu, Moscow 1979 Korchnoi-Matanovic, Palma de Mallorca 1968 Capablanca-Fine, New York 1931 Cintron-Botvinnik, Munich 1958 Flohr-Botvinnik, Moscow 1933 Botvinnik-Bronstein, Moscow 1951 Uhlmann-Gligoric, Hastings 1970/1971 Polugaevski-Ivkov, Belgrade 1969 Also, Day-Chandler, Brighton 1980 is particularly good as a example of the two bishops' power - even though Chandler was the exchange down: two bishops and rook versus two rooks(!) and knight. I'm sure that if you managed to find these (with annotations!) - or others from borrowed books from friends or the library - they should help make it clear why/how they're advantageous. I'm equally certain that all those better than me could explain these finer points to you so that you can better understand what's happening in the above games - but I'll have a go for starters... In the simplest cases - involving a single bishop (without any other piece) - the options for both sides are clear: Same Colour: Put your pawns on the opposite colour to your bishop => blockading opponent's pawns on the same colour as his bishop, restricting his bishop's space/mobility, whilst preventing him from attacking your pawns; Opposite Colour: In the endgame, this means that a passed pawn may not be queened - your bishop can only protect it as long as it stands on the same colour, it can't go further because the opponent's bishop can capture it. Hence the reason for the tendency - not guarantee! - of their leading to draws. Add a second bishop and everything changes! In the first case, one's pawns are no longer immune from attack - if the opponent has the two bishops. Of course, a knight could attack them as well - but only half the time that a bishop could, so they are never immune. You don't get the chance to do something to protect them whilst the knight's on the same colour square as your pawns. In the second, the passed pawn can advance without fear - the opponent would have to sacrifice his bishop (or knight) to stop it. [Also, pawns on both sides of the board - whether friend or foe - are more easily protected or attacked, respectively: the side with a knight or two knights would find this type of ending difficult to defend, due to the time it takes to switch the knight(s) quickly to the other side of the board.] The latter point - with a passed pawn - also applies in the middle-game positions involving hanging pawns. The two bishops work particularly well with these, as they can support the advance of the pawns - their mobility is what makes hanging pawns a strength rather than a weakness. One of the tactics used to keep them mobile involves threatening discovered attacks, from the bishops, by advancing the pawn(s) - the opponent has to move the threatened piece (king, queen, etc) out of the way of the threatened discovery, allowing you to advance the pawn - and so on. Like the rooks, the bishop - and particularly, the two bishops - thrive in open positions => you should open lines/diagonals for them, at least. Ideally, one should open up the position as much as possible. [Check through games arising from openings involving bishop-for-knight exchanges - the Ruy Lopez Exchange, Nimzo, etc - to see how players with the two bishops handle these.] Again, like the two rooks, you can force mate with the two bishops. You can't do that with two knights - and can only do so. using bishop and knight, with difficulty. Which is another way one can use the two bishops to advantage - gaining concessions from the opponent (through positional weaknesses or passivity by forcing the opponent to "waste" moves/time preventing mate-threats). As I said, I'm sure the titled players could do much better than this - but it's at least a start. Kindest regards, Dragan Glas
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