This frequent change need not be the consequence of external influences; it may proceed from the continuous activity of our own mind, in which case it indicates a characteristic unsteadiness of mind.

Evidently we should not say of a man who changes his views every moment, however much the motives of change may originate with himself, that he has character.

Only those men, therefore, can be said to have this quality whose conviction is very constant, either because it is deeply rooted and clear in itself, little liable to alteration, or because, as in the case of indolent men, there is a want of mental activity, and therefore a want of motives to change; or lastly, because an explicit act of the will, derived from an imperative maxim of the understanding, refuses any change of opinion up to a certain point.
Now in War, owing to the many and powerful impressions to which the mind is exposed, and in the uncertainty of all knowledge and of all science, more things occur to distract a man from the road he has entered upon, to make him doubt himself and others, than in any other human activity.
The harrowing sight of danger and suffering easily leads to the feelings gaining ascendency over the conviction of the understanding; and in the twilight which surrounds everything a deep clear view is so difficult that a change of opinion is more conceivable and more pardonable.

It is, at all times, only conjecture or guesses at truth which we have to act upon.

This is why differences of opinion are nowhere so great as in War, and the stream of impressions acting counter to one's own convictions never ceases to flow.