"The military art is not an accomplishment, an art for dilettante, a sport. You do not make war without reason, without an object, as you would give yourself up to music, painting, hunting, lawn tennis, where there is no great harm done whether you stop altogether or go on, whether you do little or much. Everything in war is linked together, is mutually interdependent, mutually interpenetrating. When you are at war you have no power to act at random. Each operation has a raison d'etre, that is an object; that object, once determined, fixes the nature and the value of the means to be resorted to as well as the use which ought to be made of the forces."

“If France has a firm hold of the Rhine, she may be at rest, for she can be sure of reparations and security; without the Rhine she has neither. All that may be offered or given in exchange is valueless, illusory, empty. That is the position I took up immediately. We must have the Rhine line; we want nothing more and will take nothing less.”

“Germany is about to join . It will be alleged that she conforms in spirit to that of the League. If you hope that she will desire to maintain the frontiers forced on her, which she has never acknowledged in her heart, and which, bluntly speaking, she loathes and yearns to destroy—if you can hope that, you must have more than your share of naïveté.”

“Unjustly Accused: Marshal Ferdinand Foch and the French 'Cult of the Offensive'”

“To be disciplined does not mean being silent, abstaining, or doing only what one thinks one may undertake without risk; it is not the art of eluding responsibility; it means acting in compliance with orders received, and therefore finding in one's own mind, by effort and reflection, the possibility to carry out such orders. It also means finding in one's own will the energy to face the risks involved in execution.”

“This absence of similarity among military questions naturally brings out the inability of memory to solve them; also the sterility of invariable forms, such as figures, geometrical drawings , plans , etc. One only right solution imposes itself : namely, the application, varying according to circumstances, of fixed principles.”

“This is not a peace. It is an armistice for 20 years.”