Imagine playing a game where you have the option to sacrifice a whole rook to get two whole bishops, what do you do? This is an interesting situation that a lot of people have found themselves into but cannot take advantage.
This article will help you in this problem, here is what I know:
Two bishops are better than one rook. Two bishops at the center of the board covers a total of 28 squares. The rook only covers 15 squares in the center. The two bishops are better than a single rook if both are fully active. Two bishops are equal to 6 points while a rook is only equal to 5 points.
This question is simple yet can be complicated at the same time, a rook is a whole rook after all, and some people disagree in making the bishop pair as the superior one. At the end of this article I am sure that you will be agreeing with me, keep on reading if you are interested.
Why are the two bishops so strong?
The two bishops are strong since they cover a lot of squares when the position is open. The rook covers a lot of squares which is why it is powerful, but not as much as the bishop pair. The rook in itself is only a bit better than a single bishop.
The bishop coupled with 1-2 pawns may arguably be enough of a compensation for a single rook. This tells you how strong the bishop pair is.
The bishop pair is way more valuable than a single rook
The bishop pair is just too strong for a single rook, what a single rook offers can probably be doubled by the bishop pair.
The bishop pair is just easier to play since they can defend the king while escorting the passed pawns during the endgame, they cover more squares after all.
I actually thought that this is not much of a debate, the only reason that a single rook is more valuable than a single bishop is because the pawns move vertically (which makes it easier for the rook to intercept).
If the pawns move diagonally then the rook would be as valuable as the knight, and the bishop will be as valuable as the rook in the modern version.
So bishop pair is not in question, even though they cannot cover vertical/horizontal squares they can definitely intercept pawns better than a single rook.
The difference in power between a rook and a bishop is not that much in the first place, if you throw in another bishop then the answer becomes clear.
There are some that say that the value of the rook is about the same as with two bishops, this is wrong.
Two bishops are way more useful than a single rook since they can cover more squares and escort a passed pawn just fine.
Isn’t the rook almost as strong as the queen?
Well I wouldn’t say that the rook is almost as strong as the queen. The queen is basically a combination of a rook and a bishop which makes it way stronger. And if we are talking about a whole queen then the bishop pair has a fair shot.
Bobby Fisher vs. Larsen game 1 famously featured a queenless dominant game by Bobby. Fischer dominated the queen with his own bishop pair, that is how valuable the bishop pair is.
Two bishops are worth 6 points, one rook is only worth 5 points
Upon playing lichess or chess.com you will be introduced to the concept of reinfeld values, basically how many points each individual piece has which can be used to determine which side is better.
This is not an absolute system since the values can differ from position to position, however, it is still a solid rough estimate.
If we are going to adhere to the standard valuation, a single bishop should be worth around 3 points (and a total of 6 if we have two of them).
A single rook should only be about 5 points (or even 4 in some scales) which does not even compare, the bishop pair is really just more valuable than a single rook.
If the standard valuation is equal there will be some debate about this question (such as the knight vs. bishop) but even basing from this, we can tell that the bishop pair is more valuable than the rook.
It is not, again, an absolute determination, but with a whole point above we can definitely say that the difference is enough in most positions.
There are even versions of the piece value system which puts the 2 bishops a whole 2 points ahead of a single rook; the difference in value can change depending on the system used.
The point is that the bishop pair is higher in any system, this proves that at least conceptually, two bishops are better than one rook.
Are the reinfeld values even trustworthy?
Well there is a lot of criticism in evaluating positions with the reinfeld value. Critics argue that positions are dynamic, you cannot put a value on a single piece. A passed pawn can be way more valuable than a knight for example.
The value of the pawn and pieces are relative to the position I agree, however it is still trustworthy. It is a good rough estimate of what the pieces are likely to be worth. It can change but for beginners this will be really helpful, it can apply in many cases.
The bishop pair covers more squares compared to a single rook
In most positions the bishop pair will be much better than a single rook, a bishop pair in some instances rivals the power of the queen (Fischer vs. Larsen).
They can defend an exposed king while protecting the passed pawns, and if you think about it, a bishop is basically a rook that moves diagonally.
Just like the rook, a single bishop can cover a chess board from end to end and pretty much dominate as long as the position is open.
As I have mentioned earlier, the rook is only more valuable since it is instrumental in the opposition/escort of passed pawns.
To prove that two bishops cover more squares than a single rook, place that 2 bishops at the center of the board and note how many squares they cover together.
The bishop pair (at the center) covers a total of 28 squares together, so many plays can be available with this much range.
A single rook only covers a total of 15 squares, almost half less of what the two bishops can cover together.
A single rook will be too overwhelmed just by looking at these numbers, and practical play has proven that the bishop pair is just better generally.
The rook can only be better than two bishops if it is more active
As with all rules there will always be an exemption, and the only way I can think of in this case is if the single rook is active while the bishop pair (or even just one bishop) is blockaded by pawns.
In instances like these, the piece that is more open will cover more squares and will therefore be considered better.
This is the only situation that I can think of where a rook outcompetes a bishop pair (when the bishop pair is not that active), but this is rare in open positions.
If the position is closed on the other hand, then it is likely that the rook is also not that active.
We have to remember that rooks are usually not that active in the opening/middlegame whereas the bishops do have key roles even in these phases.
In fact, most of the time, rooks are not that useful until the endgame.
This means that if we are going to bet which one is more likely to be active between a single rook and two bishops, the two bishops is the better bet.
However situations like this do exist even if they are rare, and in cases where the bishop pair (or even just one if the bishop) is blockaded, a single rook would be more powerful.
A single bishop definitely does not compare to a single rook, and two bishops that are not doing anything will lose to a whole rook.
Sometimes it can be difficult to assess whether certain piece combinations are better than the other, this is one example of these cases. One cannot just look at a simple system like the Reinfeld values to truly comprehend the question, asking someone with more experience is better.
Or you can just type stuff in the Google search bar and let it do the work. This article is one of the opportunities that allowed me to answer this question for those who are wondering. In short, the two bishops are better than a whole rook, thank you for reading.