The Slav: holding the centre without shutting the bishop in

The key idea

...c6 instead of ...e6 keeps the c8 bishop's exit open. Black can also help himself to the c4 pawn, and the key is not to try to keep it: you take it to gain time and give it back when White claims it, not to hang on to it.

Example 1 · The bishop gets out, which is what this is all about

1.d4 d5 2.c4 c6 3.Nf3 Nf6 4.Nc3 dxc4. Black takes the pawn and, at the first opportunity, brings the bishop to f5.

1. a4 White prevents ...b5 straight away, which would be the attempt to hold on to the extra pawn. It's the correct move and it has a cost worth seeing: it permanently weakens b4, where Black will be able to plant a piece with no pawn to bother it.
2. Bf5 And here's the Slav's reason for existing. In a normal Queen's Gambit this bishop would be staring at its own e6 pawn for thirty moves. Here it gets out on move 5, onto an open diagonal, and only AFTERWARDS will I play ...e6 to shut the house. The order is everything: bishop first, pawn second.
3. Ne5 The knight jumps into the centre, prepares to recover the c4 pawn and eyes f7. White is in no hurry for the pawn: he knows he gets it back whenever he likes.
4. Nbd7 The knight via d7, the route my own c6 pawn leaves it. That's the price of the system and you accept it without drama: the piece that goes to c6 in other openings goes to d7 here, and from there it contests e5 and supports ...c5 later on.
5. Nxc4 White recovers the pawn, exactly as planned from the start.
6. Qc7 And Black has placed the queen without spending a single tempo defending a pawn that was never his. There's the judgement that saves a lot of people in this opening: the c4 pawn is taken to gain developing tempi while White recovers it, not to keep it.
7. g3 White prepares the fianchetto and a comfortable position.
8. e5 A central break and a level position. Tally of the operation: good bishop solved, not one pawn weakness, development complete and a strike in the centre on move 9. That's what ...c6 buys you over ...e6.

Example 2 · Trying to keep the pawn: what actually happens

With 5.e3 b5 Black clings to the c4 pawn. Now White is teaching — and there's no spectacular punishment, there's something better.

1. a4 Against a pawn chain propping up extra material, you play with another pawn. I hit b5 and force him to decide: if he captures, he opens the a-file towards his own rook; if he pushes, his chain is left with nothing behind it.
2. b4 Black pushes and kicks my knight. He manages to hold the c4 pawn a few moves longer, and in exchange his b- and c-pawns are now hanging in mid-air, with no pawn defending them.
3. Na2 The knight to the rim, which looks ugly and is exact: from a2 it hits the b4 pawn and it's heading for c1 and b3 or d3, where it will recover c4 comfortably. When a piece has a clear destination, the square it passes through doesn't matter.
4. e6 Black shuts the house. Notice what has happened along the way: he played ...b5 and ...b4 to hold a pawn, and in the end he has had to play ...e6 anyway — which means the c8 bishop is shut in, exactly what the Slav was designed to avoid.
5. Bxc4 And the pawn comes home. No combination required: just pushing a pawn and manoeuvring a knight.
6. Bb7 The bishop comes out through the only door it has left, the long diagonal.
7. b3 I prop up my bishop and finish placing my pieces.
8. Bd6 Honest valuation, because this is where most people expect a punishment that never arrives: the position is LEVEL. Keeping the pawn doesn't lose the game. What it does is swap an opening where your bishop comes out free for one where it ends up shut in, all for a pawn you were going to give back anyway. That's the reason not to do it — not fear of a refutation, but that the deal doesn't pay.

Practice

You have the c4 pawn and White has just played a4 to stop you holding it. Forget the pawn: use it as an excuse to develop, and first bring out the piece this whole opening is played for.

1. The bishop, out into the street. In the Queen's Gambit with ...e6 this piece spends half the game shut in; here it's out on move 5. Bring out the piece that ...c6 keeps free, and do it BEFORE playing ...e6.
2. Via d7, the route your own c6 pawn leaves it. The price of the system, accepted without drama. Develop the b8 knight. Its natural square is taken by your own pawn: find the other one.
3. And not one tempo spent defending the pawn. You took it to gain development while he recovered it. Place the queen on the c-file, without trying to hold on to anything.
4. A central break with everything developed. Bishop solved, no weaknesses and the game level from move one. You're ready: strike the centre with the e-pawn, two squares.

The Slav in four moves and with no theory. Keep the two ideas and they'll cover the whole opening: ...c6 instead of ...e6 so the c8 bishop gets out before anything is shut, and the c4 pawn is taken to gain time, never to keep it. And keep example 2's lesson, which goes beyond chess: when defending something you've taken forces you to give up the reason you took it, the deal has stopped paying.