All these attempts at theory are only to be considered in their analytical part as progress in the province of truth, but in their synthetical part, in their precepts and rules, they are quite unserviceable.

They strive after determinate quantities, whilst in war all is undetermined, and the calculation has always to be made with varying quantities.

They direct the attention only upon material forces, while the whole military action is penetrated throughout by intelligent forces and their effects.

They only pay regard to activity on one side, whilst war is a constant state of reciprocal action, the effects of which are mutual.

13 As a rule they exclude genius

All that was not attainable by such miserable philosophy, the offspring of partial views, lay outside the precincts of science and was the field of genius, which raises itself above rules.

Pity the warrior who is contented to crawl about in this beggardom of rules, which are too bad for genius, over which it can set itself superior, over which it can perchance make merry! What genius does must be the best of all rules, and theory cannot do better than to show how and why it is so.

Pity the theory which sets itself in opposition to the mind! It cannot repair this contradiction by any humility, and the humbler it is so much the sooner will ridicule and contempt drive it out of real life.

14 The difficulty of theory as soon as moral quantities come into consideration

Every theory becomes infinitely more difficult from the moment that it touches on the province of moral quantities. Architecture and painting know quite well what they are about as long as they have only to do with matter; there is no dispute about mechanical or optical construction. But as soon as the moral activities begin their work, as soon as moral impressions and feelings are produced, the whole set of rules dissolves into vague ideas.

The science of medicine is chiefly engaged with bodily phenomena only; its business is with the animal organism, which, liable to perpetual change, is never exactly the same for two moments. This makes its practice very difficult, and places the judgement of the physician above his science; but how much more difficult is the case if a moral effect is added, and how much higher must we place the physician of the mind?

15 The moral quantities must not be excluded in war

But now the activity in war is never directed solely against matter; it is always at the same time directed against the intelligent force which gives life to this matter, and to separate the two from each other is impossible.

But the intelligent forces are only visible to the inner eye, and this is different in each person, and often different in the same person at different times.

As danger is the general element in which everything moves in war, it is also chiefly by courage, the feeling of one’s own power, that the judgement is differently influenced. It is to a certain extent the crystalline lens through which all appearances pass before reaching the understanding.

And yet we cannot doubt that these things acquire a certain objective value simply through experience.

Everyone knows the moral effect of a surprise, of an attack in flank or rear. Everyone thinks less of the enemy’s courage as soon as he turns his back, and ventures much more in pursuit than when pursued. Everyone judges of the enemy’s general by his reputed talents, by his age and experience, and shapes