Albert wrote:
In Reuben Fine's 'The Ideas Behind Chess Openings' page 7 he wrote:

'OPENINGS WITH 1 P-K4, P-K4

Both White's and Black's initial moves are perfectly natural and
normal: both assist development and affect vital central squares.
As long as Black can retain symmetry, White can lay no claim to an
advantage. Consequently the task is to compel the defender to give
up his strong center positions, in other words to abandon his P at
K4. White can achieve this aim only by playing P-Q4.'

Why?

Because, once Black has defended his pawn on e5 by advancing his
queen's pawn, White can only capture the Pe5 with a pawn of his own
(assuming he doesn't want to lose material). The only pawns that can
capture on e5 are the d-pawn and the f-pawn and advancing the f-pawn
weakens White's king by opening up the e1-h4 diagonal to Black's queen
and dark-squared bishop.

The alternative would be for White to try to remove the Pd6 and then
take the Pe5 with a piece. However, dislodging the Pd6 will take an
awfully long time. That has to be done with a pawn, too, since the
Pd6 is protected by the Pc7.

'If Black then replies with PXP he will be left with a pawn at Q3
(eventually)...'

Why?

Three reasons.

1) White will almost surely have played Nf3 before he plays d4. So,
when d4 is played, e5 is attacked twice. If Black isn't going to lose
material, it needs to be defended twice, too. The most natural way is
to play ... d6 and the alternatives are bad: ... Qe7 blocks in the
king's bishop; ... Qf6 blocks in the king's knight; ... Bd6 blocks in
the queen's bishop and demotes the king's bishop to acting as little
more than a pawn.

2) It discourages White from playing e5.

3) It lets Black get his queen's bishop out in the most natural way.
The alternative is to fianchetto it (i.e., play ... b6 and ... Bb7),
which is slower.


Dave.

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