In war, while everything is simple, even the simplest thing is difficult. Difficulties accumulate and produce frictions which no one can comprehend who has not seen war.

War is the realm of uncertainty; three quarters of the factors on which action is based are wrapped in a fog of greater or lesser uncertainty.

In war everything is simple, but it's the simple things that are difficult.

If we do not learn to regard a war, and the separate campaigns of which it is composed, as a chain of linked engagements each leading to the next, but instead succumb to the idea that the capture of certain geographical points or the seizure of undefended provinces are of value in themselves, we are liable to regard them as windfall profits.

We repeat again: strength of character does not consist solely in having powerful feelings, but in maintaining one’s balance in spite of them. Even with the violence of emotion, judgment and principle must still function like a ship’s compass, which records the slightest variations however rough the sea.

All war presupposes human weakness and seeks to exploit it.

In short, absolute, so-called mathematical, factors never find a firm basis in military calculations. From the very start, there is an interplay of possibilities, probabilities, good luck and bad, that weaves its way throughout the length and breadth of the tapestry. In the whole range of human activities, war most closely resembles a game of cards.