The spirit and other moral qualities which animate an Army, a General,
or Governments, public opinion in provinces in which a War is raging,
the moral effect of a victory or of a defeat, are things which in
themselves vary very much in their nature, and which also, according
as they stand with regard to our object and our relations, may have an
influence in different ways.

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.