hastens the development of his pieces by equally good Pawn moves.

The only Pawn moves which fit this description are moves with the
King's or Queen's Pawns as they open lines for Queen and Bishop--
apart from an additional square for the Knight--while the other
Pawns cannot free the way for more than one piece. Whether the
move with the King's Pawn or the Queen's Pawn is better when
beginning the game is impossible to say. In neither case can it
be proved that White can obtain an advantage which is sufficient
to win the game. With correct play on both sides it can be only
White who gains an advantage, for he has the first move and so he
is one move ahead of Black in the development as long as he does
not waste any time on maneuvers which do not increase the
mobility of his pieces.

By the mobility of a piece is meant the number of squares
accessible to it. A Bishop or a Rook which stands in an
unobstructed file is obviously worth more than one whose sphere
of action is limited on account of his way being blocked. This
does not mean, however, that a Bishop or a Knight to whom, at a
certain moment, three or four squares are accessible, is more
valuable than a Rook who at the same moment can go only to one or
two squares; for a few moves later the Rook might be in
possession of his full freedom while the action of the Bishop or
the Knight might be hampered. It is, therefore, best to value the
pieces according to their latent strength, that is, the strength
which is likely to show in the ending after all temporary
obstructions have been removed. The comparative values given for
the different men on page 42 will serve as good guide in most
cases. It is not advisable though to give up a minor piece for