But it is almost impossible to communicate with them [one's spies in the enemy camp] and receive the information they possess ... Even when the general receives from his spies information of movements, he still knows nothing of those which may since have taken place, nor of what the enemy is going finally to attempt.

A cherished cause and a general who inspires confidence by previous success are powerful means of electrifying an army.

A state attacked by another which renews an old claim rarely yields it without a war: it prefers to defend its territory, as is always more honorable. But it may be advantageous to take the offensive, instead of awaiting the attack on the frontiers.

The surprise of an army is now next to an impossibility. ... Prearranged surprises are rare and difficult because in order to plan one it becomes necessary to have an accurate knowledge of the enemy's camp.

One of the surest ways of forming good combinations in war would be to order movements only after obtaining perfect information of the enemy's proceedings. In fact, how can any man say what he should do himself; if he is ignorant what his adversary is about?

This [a surprise attack] is an operation by no means to be despised in war, although it is rare, and less brilliant than a great strategic combination which renders victory certain even before the battle is fought.

As the excited passions of hostile people are of themselves a powerful enemy, both the general and his government should use their best efforts to allay them.