On the Advantage brought about by a Simultaneous Attack upon Several Objects.
But also when the assailant has no superiority in pieces nor an exposed King as object of attack he has a multitude of aims to achieve which would procure him an advantage, for the capture of any officer or even of the modest Pawn may be of great value; to capture is, _ceteris paribus_, a gain if the opponent cannot recapture, as we know from our first proposition.
True, to threaten an officer is rarely opportune, because the officer is either "guarded," i.e., defended by its comrades in that they dominate its square and therefore threaten with capture any and every piece capturing the officer - or else the officer, being very mobile, simply takes to flight. But that is not so when several attacks of this nature take place at one and the same time. According to the fundamental rules, the players may move only one piece at a time; except when castling, hence, in case of a simultaneous attack on several pieces, not all of the assailed pieces can fly at the same moment; some must therefore tarry and suffer the consequences. To save them requires an extraordinary effort, principally a hurried counterattack by the flying officers themselves against the adverse King or on valuable pieces of the opponent, so as to prevent him from capturing one of the pieces that have fallen into his power and to make possible their flight; and this great effort has to be made very quickly and with energy, else a catastrophe is imminent.
When a Bishop, Rook or Queen attacks a piece which by its flight would expose a comrade, possibly the King, to capture, the defender is in the same predicament, since flight may be out of the question. In that case the attacked piece has to be fortified as far as possible or else, if the defence fails, has to sell its life as dearly as possible. If the piece protects the King, whose life is precious before all else, the piece is incapable of flight, it is pinned and must fight desperately. Worse still, if the King itself is assailed, it cannot defend by obstruction, unless one of its officers can aid the King by obstructing the attack of the enemy or, better still, by slaying the aggressor, the King must fly and abandon such piece as might be exposed by his flight.