_All movements of Corps Offensive should be governed by the POSITION of
the hostile army, and all movements of Corps Defensive should be governed
by the MOVEMENTS of the hostile army._
As soon as the enemy begins a movement, his intentions become clear. It
is then possible to make precise calculations.
But be not hasty to build conclusions upon uncertain information and
do not take any resolutions until certain what are the numbers, the
position, the objectives, and the projects of the enemy.
However interesting an undertaking may appear, one should not be seduced
by it while ill-informed of the obstacles to be met and the possibility
of not having sufficient force in the theatre of action.
Chimerical schemes should be abandoned at their inception. Reason,
instead of extravagancies of the fancy, always must be the guide. Men,
most courageous, often undertake fearful difficulties, but impracticable
things they leave to lunatics.
In all situations, one must beware of venturing beyond his depth. It is
wiser to keep within the limits which the knowledge we possess shall
prescribe.
Especially in crises, one must proceed most cautiously until sure
information is acquired; for over-haste is exceedingly dangerous,
when exact knowledge is lacking of the enemy’s numbers, position, and
movements.