Not to use cavalry against unbroken infantry except in some case of special emergency, only to use firearms within effective range in the combat, to spare the forces as much as possible for the final struggle -- these are tactical principles. None of them can be applied absolutely in every case, but they must always be present to the mind of the chief, in order that the benefit of the truth contained in them may not be lost in cases where that truth can be of advantage.

If from the unusual cooking by an enemy’s camp his movement is inferred, if the intentional exposure of troops in a combat indicates a false attack, then this way of discerning the truth is called rule, because from a single visible circumstance that conclusion is drawn which corresponds with the same.

If it is a rule to attack the enemy with renewed vigour, as soon as he begins to limber up his artillery in the combat, then on this particular fact depends a course of action which is aimed at the general situation of the enemy as inferred from the above fact, namely, that he is about to give up the fight, that he is commencing to draw off his troops, and is neither capable of making a serious stand while thus drawing off nor of making his retreat gradually in good order.

Regulations and methods bring preparatory theories into the conduct of war, in so far as disciplined troops are inoculated with them as active principles. The whole body of instructions for formations, drill, and field service are regulations and methods: in the drill instructions the first predominate, in the field service instructions the latter. To these things the real conduct of war attaches itself; it takes them over, therefore, as given modes of proceeding, and as such they must appear in the theory of the conduct of war.

But for those activities retaining freedom in the employment of these forces there cannot be regulations, that is, definite instructions, because they would do away with freedom of action. Methods, on the other hand, as a general way of executing duties as they arise, calculated as we have said, on an average of probability, or as a dominating influence of principles and rules carried through to application, may certainly appear in the theory of the conduct of war, provided only they are not represented as something different from what they are, not as the absolute and necessary modes of action (systems), but as the best of general forms which may be used as shorter ways in place of a particular disposition for the occasion, at discretion.

But the frequent application of methods will be seen to be most essential and unavoidable in the conduct of war, if we reflect how much action proceeds on mere conjecture, or in complete uncertainty, because one side is prevented from learning all the circumstances which influence the dispositions of the other, or because, even if these circumstances which influence the decisions of the one were really known, there is not, owing to their extent and the dispositions they would entail, sufficient time for the other to carry out all necessary counteracting measures -- that therefore measures in war must always be calculated on a certain number of possibilities; if we reflect how numberless are the trifling things belonging to any single event, and which therefore should be taken into account along with it, and that therefore there is no other means to suppose the one counteracted by the other, and to base our arrangements only upon what is of a general nature and probable; if we reflect lastly that, owing to the increasing number of officers as we descend the scale of rank, less must be left to the true discernment and ripe judgement of individuals the lower the sphere of action, and that when we reach those ranks where we can look for no other notions but those which the regulations of the service and experience afford, we must help them with the methodic forms bordering on those regulations. This will serve both as a support to their judgement and a barrier against those extravagant and erroneous views which are so especially to be dreaded in a sphere where experience is so costly.

Besides this absolute need of method in action, we must also acknowledge that it has a positive advantage, which is that, through the constant repetition of a formal exercise, a readiness, precision, and firmness is attained in the movement of troops which diminishes the natural friction, and makes the machine move easier.