Why 6...e5 in King's Indian?

Question

I'm a hobbyist chess player, mostly playing online correspondence. I often play the King's Indian defense as Black, but there seems to be a key idea in the opening that I'm missing. Specifically, I don't understand why 6...e5 is so commonly played in so many variations, for example:

[fen ""]
[StartFlipped "1"]
1. d4 Nf6
2. c4 g6
3. Nc3 Bg7
4. e4 d6
5. Nf3 O-O
6. Be2 e5

It seems to me that in this position by playing 6...e5 Black blocks his own fianchettoed bishop, and given that White frequently pushes d5 later on, the diagonal is unlikely to reopen up any time soon. It seems to me that something like 6...c5 would be a much more natural move, logically setting up a queenside attack with the central pawn chain supporting the dark-squared bishop on the long diagonal.

Clearly I'm missing something here, given 6...e5's popularity relative to 6...c5. So my questions are

1. Why is 6....e5 so much more popular than 6...c5, and
2. What is Black supposed to do with his dark-squared bishop after 6...e5?

Answer 1

It is good to think more concretely here. After move like e5 three things can happen. White can take on e5, white can play d5 or black will one day play exd4 himself.

1. Taking on e5 never wins a pawn and creates a hole on d4. For good reason not very popular

2. With d5 your bishop is now bad, but the position for black is good, easy and funny to play. An attack with f5 f4 g5 h5 g4 Ng6 Nh4 is very dangerous. Bishop often joins the attack in later stages from h6 and is often use on f8 till its time to hold the queenside for a little longer. Also maneuver Rf8-f7-g7 us typical to protect 7th rank and attack at the same time. Find games of Nakamura how he murdered some 2700+ players just rolling on the kingside.

3. Tactics say it is not so easy for white to achieve exchange on d4 under good terms. After 7...Nc6 there are no useful moves for white and pressure against centre is already too strong. Popular d5 goes to (2) and Be3 runs to Ng4, even if it is also variation.

So there are three good scenarios for black after e5 and in comparison to some Maroczy bind or benoni structure I think they are both better and more interesting to play.

Note1: Many c5 style players play c5 already on move 2, by the way.

Note2: Calm players with no intention of attacking don't play kings indian in the first place, playing Nimzo Indian, Slav etc...

So everybody wants to play e5 and win!

Answer 2

After 6....e5 the centre usually gets closed with white playing d5. This closed centre helps black in his kingside attack with f5, g5, ... The dark squared bishop sometimes goes to f8 from where it helps to support the d6 pawn which can get weak if white attacks on the queenside.

The positions after c5 are completely different resembling the Sicilian dragon or Benoni to which it can transpose. Here it is white who is attacking on the kingside.

So I guess e5 is more popular because black players of the king's Indian prefer to attack the king more than defending.

Answer 3

E5 starts the kingside development/attack that Black wants. The reason he is doing this is because he has more pieces developed on the kingside than White. Eventually, he will move f5, and even advance his g pawn.

Yes, e5 reduces the effectiveness of the black bishop in the center and long diagonal. But that's not the point. If Black wants to be aggressive the kingside, advancing his pawns, the bishop is needed at g7 for defense.

E5 is what gives the King's Indian its character, and it is at this point that the opening becomes the King's Indian. Before it, Black had a variety of potential center and queen's side defenses such as the Gruenfeld. With e5, Black commits to playing on the king, not the queenside.

Answer 4

This always used to puzzle me when I was starting out. Now I think of it like this. ..e5 increases the pressure that the fianchettoed Bishop exerts on d4, and White must decide what to do about it.

1. He can exchange pawns d4xe5. As already noted this is not very ambitious and leaves Black with fewer problems than he might have had.

2. He can leave the tension as it is but to some extent that just puts the decision off. Black can also leave the tension unresolved, but eventually he usually exchanges e5xd4 and now the Bishop is fully in play.

3. He can push d5, and now the Pawn structure is such that almost inevitably White will attack on the Q-side, and Black on the K-side. True, that Bishop is now confined and might become a liability in the endgame, but Black has created an inbalance that they find congenial4

You should only play the lines with ..e5 if you are happy with all of these outcomes.