Fundamental Principles : The Double Threat

You should at all times be on the alert for a chance to put the enemy under the necessity of doing two things at once - and you should try to avoid putting yourself into such a difficult situation. This means that the key to success in chess is A DOUBLE THREAT. A threat to one enemy piece alone is normally parried with ease and is worthless except for some reason ulterior motive. But a double threat is terrific.

How to Practice

You can play chess with the wizards of the chess world, living or dead, anytime and anywhere you like. The wizards' games are printed and you just play the games over, understanding a little at first but gradually more and more. You can imagine how a player would improve if he had a champion always at his shoulder to show him what that champion would play instead of the move the player himself had thought out.

At each move you should spend a little time thinking out a move yourself, then uncover the text move and compare it to yours. Looking first is useless.

From Guide to Good Chess pg. 10

The Middlegame in Chess

According to Purdy the middlegame in chess goes as follows when two strong and evenly matched opponents meet over the board:

One player obtains a positional advantage; the opponent's difficulties increase until he loses some material; perhaps only a pawn; the player with the material advantage then strives to exchange pieces so as to bring about an endgame and finally Queen a pawn. After that, mate can be forced no matter how well the opposing King is defended. Naturally, the player who has lost the material throws all kinds of spanners in the works. If the disadvantaged player is more skillful than his opponent, he will usually win, even after making some early blunder that gives him a "losing" game.

Rooks are the Key

Any opening that caters to the rooks will automatically be a good one for the other pieces.

We should test any opening chiefly by the prospects it offers to ambitious young rooks.

 How is a rook to blossom? In one way only: through an exchange of pawns. Such an exchange need not be hurried. It is sufficient if the possibility of exchange is there on the board, ready to be utilized at any time.

Guidelines for Playing Endgames with Bishops of Opposite Color

1. Place your pawns on the square of opposite color to that of your own bishop.
2. Use your King to command squares not controlled by your bishop.
3. Look to secure a passed pawn, or at least complicate the position by playing on both wings.

Purdy Endgame Quotes

Place your rook BEHIND a passed pawn if the pawn has crossed the middle line.

The King is a champion pawn-blockader. Therefore, prefer to have passed pawns on the side where the enemy King does not stand.

Rook on the seventh rank is particularly deadly if the enemy King is confined to the eighth rank.

In rook endings, strive to decrease the mobility of the enemy rook or rooks and to increase the mobility of your own.

Whether an advanced pawn is yours or the opponent's, our rook is best placed behind it.

Four Tests on Where a Piece Should Go in the Opening

The ideal square for a piece in the opening will stand the following tests:

1. The piece can go there in one move.
2. The piece will be effectively posted there.
3. The piece will not suffer from exposure.
4. The piece will not unduly obstruct any of its own forces.

Rarely can you find a square that passes all these tests, but try to get the square that passes test 3 and as many of the others as possible.

- CJS Purdy