Although little or nothing can be said about these things in books, still they belong to the theory of the Art of War, as much as everything else which constitutes War.  For I must here once more repeat that it is a miserable philosophy if, according to the old plan, we establish rules and principles wholly regardless of all moral forces, and then, as soon as these forces make their appearance, we begin to count exceptions which we thereby establish as it were theoretically, that is, make into rules; or if we resort to an appeal to genius, which is above all rules, thus giving out by implication, not only that rules were only made for fools, but also that they themselves are no better than folly.

Even if the theory of the Art of War does no more in reality than recall these things to remembrance, showing the necessity of allowing to the moral forces their full value, and of always taking them into consideration, by so doing it extends its borders over the region of immaterial forces, and by establishing that point of view, condemns beforehand every one who would endeavour to justify himself before its judgment seat by the mere physical relations of forces.

Further out of regard to all other so-called rules, theory cannot banish the moral forces beyond its frontier, because the effects of the physical forces and the moral are completely fused, and are not to be decomposed like a metal alloy by a chemical process.  In every rule relating to the physical forces, theory must present to the mind at the same time the share which the moral powers will have in it, if it would not be led to categorical propositions, at one time too timid and contracted, at another too dogmatical and wide.  Even the most matter-of-fact theories have, without knowing it, strayed over into this moral kingdom; for, as an example, the effects of a victory cannot in any way be explained without taking into consideration the moral impressions.  And therefore the most of the subjects which we shall go through in this book are composed half of physical, half of moral causes and effects, and we might say the physical are almost no more than the wooden handle, whilst the moral are the noble metal, the real bright-polished weapon.

The value of the moral powers, and their frequently incredible influence, are best exemplified by history, and this is the most generous and the purest nourishment which the mind of the General can extract from it.—­At the same time it is to be observed, that it is less demonstrations, critical examinations, and learned treatises, than sentiments, general impressions, and single flashing sparks of truth, which yield the seeds of knowledge that are to fertilise the mind.

We might go through the most important moral phenomena in War, and with all the care of a diligent professor try what we could impart about each, either good or bad.  But as in such a method one slides too much into the commonplace and trite, whilst real mind quickly makes its escape in analysis, the end is that one gets imperceptibly to the relation of things which everybody knows.  We prefer, therefore, to remain here more than usually incomplete and rhapsodical, content to have drawn attention to the importance of the subject in a general way, and to have pointed out the spirit in which the views given in this book have been conceived.