How to Judge Generals - The Fog of War

From G.F.R. Henderson's Stonewall Jackson:

As suggested in the first volume, it is too often overlooked, by those who study the history of campaign, that war is the province of uncertainty. The reader has the whole theatre of war displayed before him. He notes the exact disposition of the opposing forces at each hour of the campaign, and with this in his mind's eye he condemns or approves the action of the commanders. In the action of the defeated general he usually often sees much to blame; in the action of the successful general but little to admire. But his judgment is not based on a true foundation. He has ignored the fact that the information at his disposal was not at the disposal of those he criticises; and until he realises that both generals, to a greater or less degree, must have been groping in the dark, he will neither make just allowance for the errors of the one, nor appreciate the genius of the other.