To conduct a whole War, or its great acts, which we call campaigns, to a successful termination, there must be an intimate knowledge of State policy in its higher relations.  The conduct of the War and the policy of the State here coincide, and the General becomes at the same time the Statesman.

We do not give Charles XII. the name of a great genius, because he could not make the power of his sword subservient to a higher judgment and philosophy—­could not attain by it to a glorious object.  We do not give that title to Henry iv. (of France), because he did not live long enough to set at rest the relations of different States by his military activity, and to occupy himself in that higher field where noble feelings and a chivalrous disposition have less to do in mastering the enemy than in overcoming internal dissension.

In order that the reader may appreciate all that must be comprehended and judged of correctly at a glance by a General, we refer to the first chapter.  We say the General becomes a Statesman, but he must not cease to be the General.  He takes into view all the relations of the State on the one hand; on the other, he must know exactly what he can do with the means at his disposal.

As the diversity, and undefined limits, of all the circumstances bring a great number of factors into consideration in War, as the most of these factors can only be estimated according to probability, therefore, if the Chief of an Army does not bring to bear upon them a mind with an intuitive perception of the truth, a confusion of ideas and views must take place, in the midst of which the judgment will become bewildered.  In this sense, Buonaparte was right when he said that many of the questions which come before a General for decision would make problems for a mathematical calculation not unworthy of the powers of Newton or Euler.

What is here required from the higher powers of the mind is a sense of unity, and a judgment raised to such a compass as to give the mind an extraordinary faculty of vision which in its range allays and sets aside a thousand dim notions which an ordinary understanding could only bring to light with great effort, and over which it would exhaust itself.  But this higher activity of the mind, this glance of genius, would still not become matter of history if the qualities of temperament and character of which we have treated did not give it their support.

Truth alone is but a weak motive of action with men, and hence there is always a great difference between knowing and action, between science and art.  The man receives the strongest impulse to action through the feelings, and the most powerful succour, if we may use the expression, through those faculties of heart and mind which we have considered under the terms of resolution, firmness, perseverance, and force of character.

If, however, this elevated condition of heart and mind in the General did not manifest itself in the general effects resulting from it, and could only be accepted on trust and faith, then it would rarely become matter of history.