On War
Clausewitz (1827)

Chapter VII. Perseverance

The reader expects to hear of angles and lines, and finds, instead of these citizens of the scientific world, only people out of common life, such as he meets with every day in the street. And yet the author cannot make up his mind to become a hair’s breadth more mathematical than the subject seems to him to require, and he is not alarmed at the surprise which the reader may show.

In War more than anywhere else in the world things happen differently to what we had expected, and look differently when near, to what they did at a distance. With what serenity the architect can watch his work gradually rising and growing into his plan. The doctor although much more at the mercy of mysterious agencies and chances than the architect, still knows enough of the forms and effects of his means. In War, on the other hand, the Commander of an immense whole finds himself in a constant whirlpool of false and true information, of mistakes committed through fear, through negligence, through precipitation, of contraventions of his authority, either from mistaken or correct motives, from ill will, true or false sense of duty, indolence or exhaustion, of accidents which no mortal could have foreseen. In short, he is the victim of a hundred thousand impressions, of which the most have an intimidating, the fewest an encouraging tendency. By long experience in War, the tact is acquired of readily appreciating the value of these incidents; high courage and stability of character stand proof against them, as the rock resists the beating of the waves. He who would yield to these impressions would never carry out an undertaking, and on that account perseverance in the proposed object, as long as there is no decided reason against it, is a most necessary counterpoise. Further, there is hardly any celebrated enterprise in War which was not achieved by endless exertion, pains, and privations; and as here the weakness of the physical and moral man is ever disposed to yield, only an immense force of will, which manifests itself in perseverance admired by present and future generations, can conduct to our goal.