The Big Secret Of Opposite-Colored Bishops
The 10th world champion Boris Spassky was married three times, but unfortunately all three marriages ended in divorce. Describing his first marriage, Spassky famously said, "we were like bishops of opposite color."
When I saw this catchy phrase the first time, I thought he was talking about the most obvious feature of opposite-colored bishops: They never meet on the chessboard.
So my understanding was that Spassky and his first wife had different interests in life and therefore they lived in different worlds. From the other side, most world champions and elite players followed the well-known saying, "one chess player in a family is already too much," and therefore their spouses didn't play chess.
Yet many of these chess players were happily married their whole lives. I discussed this topic in my old article.
One day, I read a very provocative interview of Boris Spassky, and here is what he said about his marriages:
I'm trying to divorce my French wife and come out unscathed. I'm losing all my possessions!
I have already accepted some losses. In materiel. But at least I haven't lost manpower.
I had a Mustang, but after divorcing my first wife Larisa, she took it from me. She quickly sold it to some Georgians. She was a pragmatic woman.
I hope you see a pattern here. I did. Therefore I finally realized why Spassky was comparing his marriage to a position with opposite-colored bishops. The following little-known quote by Cecil Purdy explains it quite well:
In endings with bishops of opposite color, material means nothing, position is everything!
My only correction to this quote would be exchanging the word "positions" for "endings," since this rule can be applied to most positions with opposite-colored bishops, and not just endgames.
Indeed, it is common knowledge that sometimes an extra pawn (or two) is not enough to win an endgame with opposite-colored bishops. Look at this position, for example:
White has two extra pawns and one of them is a protected passed pawn, which is usually a huge advantage in most endgames—and yet he has zero chances to win. Black just needs to move his bishop back and forth on the a7-g1 diagonal. White's light-squared bishop is completely useless here.
Now let's take a look at a game that made a very strong impression on me when I started playing chess. While studying my then-favorite Dragon Sicilian, I stumbled on the following game:
The unexpected resignation in the final position was very puzzling to a beginner. Indeed, why did White give up having an extra pawn when Black didn't have any immediate threats? But the more I analyzed the position, the more clear it became that White's king is completely defenseless against the coming attack. White's light-squared bishop was completely useless for defending dark squares against his black counterpart. Indeed, material means nothing and the position is everything!
After I learned this big secret of opposite-colored bishops, it was easier for me to understand the following comment of the "Patriarch":
White could win a pawn by 35.Bxb7. Instead he moves his centralized Bd5 to d3. Why?
Here is Botvinnik's explanation: "This is the simplest. All White needs to do is Bd5-c4-d3, f2-f4, Rf1-h1 and e4-e5."
You see, Botvinnik is so uninterested in the b7 pawn that he doesn't even mention this possibility in his comments!
Indeed, why does he need a pawn if he can win with a direct attack against the opponent's king? This is very important to remember. Frequently an attack against a king is decisive when there are opposite-colored bishops on the board. The explanation is quite simple: When you attack on squares of one color, your opponent's opposite-colored bishop is completely useless for defense, and therefore it is almost like you have an extra piece in the attack!
The next game was played in a very memorable tournament where I got my GM title. I couldn't really understand what was going on at the table next to me. A very strong GM, Gata Kamsky, voluntarily went for a position where the outcome of the game was completely clear. In fact, this is exactly the kind of position that shocked me initially when I was a kid (see the game Ostermeyer-Sosonko above).
Yes, White's extra pawn is meaningless and his light-squared bishop is completely useless. Black's attack will decide the game sooner than later.
Last year I saw another example of the same deadly pattern with the same sad outcome for White:
Now you know the biggest secret of games where opponents have opposite-colored bishops: Material is nothing; position is everything!