The will to conquer is the first condition of victory.
Notes from Wikiquote
Victory is a thing of the will. | (perhaps a different and better translation of the same remark) quoted by Barbara Tuchman in The Guns of August (Random House, 1962)
Everything in war is linked together, is mutually interdependent, mutually interpenetrating.
One does simply what one can in order to apply what one knows.
The most powerful weapon on earth is the human soul on fire.
Quote text and notes from Wikiquote: Ferdinand Foch (page history), available under CC BY-SA 4.0. Source quality and labels are our own summary of what Wikiquote records.