1.e4 e5 2.Nf3 Nc6 3.Bb5 a6 4.Ba4 Nf6 5.O-O Nxe4

The Open Defense. Black takes the pawn in the center and dares White to win it back. Herr Schindler took it every time he had the black pieces against me.

6.d4 b5 7.Bb3 d5 8.dxe5 Be6 9.c3 Be7 10.Re1 O-O 11.Nd4 Qd7?

A natural developing move, and a mistake. His queen now stands on the same file as mine, with only his pawn on d5 between them. That pawn is about to become very busy.

12.Nxe6 fxe6 13.Rxe4!

The rook takes his knight, and it cannot be taken back. If 13...dxe4, the d-file is open, since my knight has left d4, and 14.Qxd7 wins his queen. I had seen this trap in a book before the war, and I had waited twelve years of postal play for someone to walk into it. I am not proud of how pleased I was.

13...Rad8

Guarding his queen, so that now the pawn really does threaten my rook, and I bring it home.

14.Re1 Bc5 15.Be3 Bxe3 16.Rxe3  Black resigned.

He was a clean piece down with nothing to show for it, and he knew it. With his resignation came a picture postcard of Kassel and a note in careful English saying that he would not fall for it twice. He did not. We played three more games over the next eight years, and he won two of them. The lesson: even with a month to think and a shelf of books, a man can walk into a hole if he does not look at what his opponent's pieces are doing. I have walked into a few myself since.

1.d4 d5 2.c4 e6 3.Nc3 c5

The Tarrasch Defense. Black accepts an isolated pawn on d5 in return for free and easy development. I played it through most of the 1970s, because I like my pieces to have somewhere to go.

4.cxd5 exd5 5.Nf3 Nc6 6.e3 Nf6 7.Be2 Bd6 8.dxc5 Bxc5 9.O-O O-O 10.b3 Re8 11.Bb2 a6 12.Rc1 Ba7

The bishop retreats to a square where his knight cannot chase it, and from a7 it looks along the diagonal toward his king's side. Remember where it stands.

13.Na4 Bg4 14.Nd4 Bxe2 15.Qxe2 Qd6 16.Nxc6 bxc6

Now my queen's-side pawns are weak, and the pawn on a6 seems to hang, since my own bishop stands in front of my rook on the a-file. Mr. Litchford took it.

17.Qxa6? Bb8!

I believe this is the best single move I have ever made by mail, and it took nineteen of my thirty days to find. The bishop steps aside, and two things happen at once. My rook on a8 now looks straight down the file at his queen, and my bishop and queen stand together on the long diagonal, threatening 18...Qxh2 mate. There is no way to meet both threats without losing at least a piece.

White resigned.

His card said, in its entirety: "Well played, sir. I did not see it. Shall we have another?" We have had eleven more since, and we are playing our twelfth now. He writes with a fountain pen, and his cards smell faintly of pipe tobacco, even after crossing an ocean.

1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 a6

The Najdorf. Madame Viens has played it against me in all five of our games.

6.Bc4

The bishop to c4, as Fischer played it. I have used it against the Najdorf for thirty years, with mixed results.

6...e6 7.Bb3 b5 8.O-O Be7 9.f4 O-O 10.f5 e5 11.Nde2

Pushing the pawn to f5 gains room on the king's side, but it also removes the pawn that guarded the long diagonal to my king. I knew that. I did not think it mattered.

11...Qb6+ 12.Kh1 Ng4

Now her queen looks down the diagonal from b6 toward my king's corner with nothing in the way, and her knight on g4 cannot be touched, because my own knight on e2 is standing in front of my queen. She threatens 13...Nf2+, forking my king and queen. 13.Qe1, guarding f2 a second time, would have held everything.

13.Rg1??

I meant to follow with h3 and g4 and drive her knight away, with my rook behind the pawns. That plan serves well in many Sicilians. But the rook on f1 was the only piece guarding f2. I wrote the move on the card, checked it twice, and mailed it after breakfast, exactly as I tell everyone to do. I had checked the wrong thing.

13...Nf2 mate.

A smothered mate. My king is walled in by its own rook and pawns, and the knight gives check from a square that nothing of mine can reach. I have shown this pattern to beginners for fifty years. Madame Viens sent her move on a card with a little knight drawn in the corner, and an apology, which was kind and quite unnecessary. The finest move of my year was hers. We began a new game the following week, and I am being very careful.