In practice we always base our preparations against an enemy on the assumption that his plans are good; indeed, it is right to rest our hopes not on a belief in his blunders, but on the soundness of our provisions. Nor ought we to believe that there is much difference between man and man, but to think that the superiority lies with him who is reared in the severest school.
Thucydides... Athenians are addicted to innovation. They are daring beyond their judgment they toil on with little opportunity for enjoying, being ever engaged in getting, they were born into the world to take no rest themselves, and to give none to others.
ThucydidesFor if many ill-conceived plans have succeeded through the still greater lack of judgment of an opponent, many more, apparently well laid, have on the contrary ended in disgrace. The confidence with which we form our schemes is never completely justified in their execution; speculation is carried on in safety, but, when it comes to action, fear causes failure.
Thucydides