But it more often happens that the correction of one premise, and the knowledge of chance events which have arisen, are not sufficient to overthrow our plans completely, but only suffice to produce hesitation.  Our knowledge of circumstances has increased, but our uncertainty, instead of having diminished, has only increased.  The reason of this is, that we do not gain all our experience at once, but by degrees; thus our determinations continue to be assailed incessantly by fresh experience; and the mind, if we may use the expression, must always be “under arms.”

Now, if it is to get safely through this perpetual conflict with the unexpected, two qualities are indispensable:  in the first place an intellect which, even in the midst of this intense obscurity, is not without some traces of inner light, which lead to the truth, and then the courage to follow this faint light.  The first is figuratively expressed by the French phrase coup d’oeil.  The other is resolution.  As the battle is the feature in War to which attention was originally chiefly directed, and as time and space are important elements in it, more particularly when cavalry with their rapid decisions were the chief arm, the idea of rapid and correct decision related in the first instance to the estimation of these two elements, and to denote the idea an expression was adopted which actually only points to a correct judgment by eye.  Many teachers of the Art of War then gave this limited signification as the definition of coup d’oeil.  But it is undeniable that all able decisions formed in the moment of action soon came to be understood by the expression, as, for instance, the hitting upon the right point of attack, &c.  It is, therefore, not only the physical, but more frequently the mental eye which is meant in coup d’oeil.  Naturally, the expression, like the thing, is always more in its place in the field of tactics:  still, it must not be wanting in strategy, inasmuch as in it rapid decisions are often necessary.  If we strip this conception of that which the expression has given it of the over-figurative and restricted, then it amounts simply to the rapid discovery of a truth which to the ordinary mind is either not visible at all or only becomes so after long examination and reflection.

Resolution is an act of courage in single instances, and if it becomes a characteristic trait, it is a habit of the mind.  But here we do not mean courage in face of bodily danger, but in face of responsibility, therefore, to a certain extent against moral danger.  This has been often called courage d’esprit, on the ground that it springs from the understanding; nevertheless, it is no act of the understanding on that account; it is an act of feeling.  Mere intelligence is still not courage, for we often see the cleverest people devoid of resolution.  The mind must, therefore, first awaken the feeling of courage, and then be guided and supported by it, because in momentary emergencies the man is swayed more by his feelings than his thoughts.