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.
PRINCIPLE
Situations always should be contemplated as they EXIST, never as they OUGHT to be, or, perhaps, MAY be.
In every important juncture, each step must be profoundly considered; as little as possible should be left to chance.
Particularly, must one never be inflated and rendered careless and negligent by success; nor made spiritless and fearful by reverses. At all times the General should see things only as they are and attempt what is dictated by that Strategetic Principle which dominates the given situation. Fortune often does the rest.
“Napoleon bending over and sometimes lying at full length upon his map, with a pair of dividers opened to a distance on the scale of from 17 to 20 miles, equal to 22 to 25 miles over country, and marking the positions of his own and of the hostile armies by sticking into the map pins surmounted by little balls made of diverse colored sealing wax; in the twinkling of an eye calculated those wonderful concentrations of his Corps d’armee upon decisive points and dictated those instructions to his Marshals which in themselves are a title to glory.”—Baron de Jomini.