Men are always more inclined to pitch their estimate of the enemy's strength too high than too low, such is human nature.
Carl von ClausewitzWe must evaluate the political sympathies of other states and the effect war may have on them. To assess these things in all their ramifications and diversity is plainly a colossal task. Rapid and correct appraisal of them clearly calls for the intuition of a genius; to master all this complex mass by sheer methodical examination is obviously impossible. Bonaparte was quite right when he said that Newton himself would quail before the algebraic problems it could pose.
Carl von ClausewitzThe general unreliability of all information presents a special problem in war: all action takes place, so to speak, in the twilight, which, like fog or moonlight, often tends to make things seem grotesque and larger than they really are. Whatever is hidden from full view in this feeble light has to be guessed at by talent, or simply left to chance. So once again for the lack of objective knowledge, one has to trust to talent or to luck.
Carl von Clausewitz