After we have thought out everything carefully in advance and have sought and found without prejudice the most plausible plan, we must not be ready to abandon it at the slightest provocation. should this certainty be lacking, we must tell ourselves that nothing is accomplished in warfare without daring; that the nature of war certainly does not let us see at all times where we are going; that what is probable will always be probable though at the moment it may not seem so; and finally, that we cannot be readily ruined by a single error, if we have made reasonable preparations.
Carl von ClausewitzWe must, therefore, be confident that the general measures we have adopted will produce the results we expect. most important in this connection is the trust which we must have in our lieutenants. consequently, it is important to choose men on whom we can rely and to put aside all other considerations. if we have made appropriate preparations, taking into account all possible misfortunes, so that we shall not be lost immediately if they occur, we must boldly advance into the shadows of uncertainty.
Carl von ClausewitzIf we consider the actual basis of this information [i.e., intelligence], how unreliable and transient it is, we soon realize that war is a flimsy structure that can easily collapse and bury us in its ruins. ... Many intelligence reports in war are contradictory; even more are false, and most are uncertain. This is true of all intelligence but even more so in the heat of battle, where such reports tend to contradict and cancel each other out. In short, most intelligence is false, and the effect of fear is to multiply lies and inaccuracies.
Carl von Clausewitz