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. CHAPTER IV. The Chief Moral Powers These are _The Talents of the Commander; The Military Virtue of the Army; Its National feeling_. Which of these is the most important no one can tell in a general way, for it is very difficult to say anything in general of their strength, and still more difficult to compare the strength of one with that of another. The best plan is not to undervalue any of them, a fault which human judgment is prone to, sometimes on one side, sometimes on another, in its whimsical oscillations. It is better to satisfy ourselves of the undeniable efficacy of these three things by sufficient evidence from history.