The general plan of campaign is frequently determined on previous to beginning operations, but the choice of lines and positions must ordinarily result from the ulterior events of the war, and be made by the general as these events occur.
As a general rule, _a line of operations should be directed upon the centre_, or _one of the extremities of the enemy's line of defence_; unless our forces be infinitely superior in number, it would be absurd to act against the front and extremities at the same time.
If the configuration of the theatre of operations be favorable to a movement against the extremity of the enemy's line of defence, this direction maybe best calculated to lead to important results.

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4.) In 1800 the army of the Rhine was directed against the extreme left of the line of the Black Forest; the army of reserve was directed by the St.Bernard and Milan on the extreme right and rear of Melas's line of defence: both operations were most eminently successful.

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5.) It may be well to remark that it is not enough merely to gain the extremity and rear of the enemy, for in that case it may be possible for him to throw himself on our communications and place us in the very dilemma in which we had hoped to involve him.