rather, if the arch ends in such a keystone, bring it prominently out; but so does this, only in order to satisfy the philosophical law of reason, in order to show distinctly the point to which the lines all converge, not in order to form out of it an algebraical formula for use upon the battlefield; for even these maxims and rules serve more to determine in the reflecting mind the leading outline of its habitual movements than as landmarks indicating to it the way in the act of execution.

28 By this point of view theory becomes possible, and ceases to be in contradiction to practice

Taking this point of view, there is a possibility afforded of a satisfactory, that is, of a useful, theory of the conduct of war, never coming into opposition with the reality, and it will only depend on rational treatment to bring it so far into harmony with action that between theory and practice there shall no longer be that absurd difference which an unreasonable theory, in defiance of common sense, has often produced, but which, just as often, narrow-mindedness and ignorance have used as a pretext for giving way to their natural incapacity.

29 Theory therefore considers the nature of ends and means -- ends and means in tactics

Theory has therefore to consider the nature of the means and ends.

In tactics the means are the disciplined armed forces which are to carry on the contest. The object is victory. The precise definition of this conception can be better explained hereafter in the consideration of the combat. Here we content ourselves by denoting the retirement of the enemy from the field of battle as the sign of victory. By means of this victory strategy gains the object for which it appointed the combat, and which constitutes its special signification. This signification has certainly some influence on the nature of the victory. A victory which is intended to weaken the enemy’s armed forces is a different thing from one which is designed only to put us in possession of a position. The signification of a combat may therefore have a sensible influence on the preparation and conduct of it, consequently will be also a subject of consideration in tactics.

30 Circumstances which always attend the application of the means

As there are certain circumstances which attend the combat throughout, and have more or less influence upon its result, therefore these must be taken into consideration in the application of the armed forces.

These circumstances are the locality of the combat (ground), the time of day, and the weather.

31 Locality

The locality, which we prefer leaving for solution, under the head of ‘Country and Ground’, might, strictly speaking, be without any influence at all if the combat took place on a completely level and uncultivated plain.

In a country of steppes such a case may occur, but in the cultivated countries of Europe it is almost an imaginary idea. Therefore a combat between civilised nations, in which country and ground have no influence, is hardly conceivable.

32 Time of day

The time of day influences the combat by the difference between day and night; but the influence naturally extends further than merely to the limits of these divisions, as every combat has a certain duration, and great battles last for several hours. In the preparations for a great battle, it makes an essential difference whether it begins in the morning or the evening. At the same time, certainly many battles may be fought in which the question of the time of day is quite immaterial, and in the generality of cases its influence is only trifling.

33 Weather