On War
Clausewitz (1827)


The manuscript on the conduct of the Grande Guerre, which will be found after my death, in its present state can only be regarded as a collection of materials from which it is intended to construct a theory of War. With the greater part I am not yet satisfied; and the sixth book is to be looked at as a mere essay: I should have completely remodelled it, and have tried a different line.

But the ruling principles which pervade these materials I hold to be the right ones: they are the result of a very varied reflection, keeping always in view the reality, and always bearing in mind what I have learnt by experience and by my intercourse with distinguished soldiers.

The seventh book is to contain the attack, the subjects of which are thrown together in a hasty manner: the eighth, the plan for a War, in which I would have examined War more especially in its political and human aspects. The first chapter of the first book is the only one which I consider as completed; it will at least serve to show the manner in which I proposed to treat the subject throughout.

The theory of the Grande Guerre, or Strategy, as it is called, is beset with extraordinary difficulties, and we may affirm that very few men have clear conceptions of the separate subjects, that is, conceptions carried up to their full logical conclusions. In real action most men are guided merely by the tact of judgment which hits the object more or less accurately, according as they possess more or less genius.

This is the way in which all great Generals have acted, and therein partly lay their greatness and their genius, that they always hit upon what was right by this tact. Thus also it will always be in action, and so far this tact is amply sufficient. But when it is a question, not of acting oneself, but of convincing others in a consultation, then all depends on clear conceptions and demonstration of the inherent relations, and so little progress has been made in this respect that most deliberations are merely a contention of words, resting on no firm basis, and ending either in every one retaining his own opinion, or in a compromise from mutual considerations of respect, a middle course really without any value. [Herr Clausewitz evidently had before his mind the endless consultations at the Headquarters of the Bohemian Army in the Leipsic Campaign 1813].

Clear ideas on these matters are therefore not wholly useless; besides, the human mind has a general tendency to clearness, and always wants to be consistent with the necessary order of things.

Owing to the great difficulties attending a philosophical construction of the Art of War, and the many attempts at it that have failed, most people have come to the conclusion that such a theory is impossible, because it concerns things which no standing law can embrace. We should also join in this opinion and give up any attempt at a theory, were it not that a great number of propositions make themselves evident without any difficulty, as, for instance, that the defensive form, with a negative object, is the stronger form, the attack, with the positive object, the weaker--that great results carry the little ones with them--that, therefore, strategic effects may be referred to certain centres of gravity--that a demonstration is a weaker application of force than a real attack, that, therefore, there must be some special reason for resorting to the former--that victory consists not merely in the conquest on the field of battle, but in the destruction of armed forces, physically and morally, which can in general only be effected by a pursuit after the battle is gained--that successes are always greatest at the point where the victory has been gained, that, therefore, the change from one line and object to another can only be regarded as a necessary evil--that a turning movement is only justified by a superiority of numbers generally or by the advantage of our lines of communication and retreat over those of the enemy--that flank positions are only justifiable on similar grounds--that every attack becomes weaker as it progresses.