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• Les avions sont des jouets intéressants mais n'ont aucune utilité militaire
  • Airplanes are interesting toys, but of no military value.
    • Said in 1911 as quoted Time : A Traveler's Guide (1998) by Clifford A. Pickover, p. 249

• One does simply what one can in order to apply what one knows.
  • The Principles of War (1913)

• Mon centre cède, ma droite recule, situation excellente, j'attaque.
  • My centre is giving way, my right is retreating, situation excellent, I am attacking.
  • Message to Marshal Joseph Joffre during the First Battle of the Marne (8 September 1914), as quoted in Foch : Le Vainqueur de la Guerre (1919) by Raymond Recouly, Ch. 6
  • Variant (American spelling): My center is giving way, my right is retreating, situation excellent, I am attacking.

• The most powerful weapon on earth is the human soul on fire.
  • As quoted in The 32d Infantry Division in World War II (1956) by Harold Whittle Blakeley, p. 3

• I am conscious of having served England as I served my own country.
  • As engraved on the statue of Ferdinand Foch on Grosvenor Square, London.

• This is not a peace. It is an armistice for 20 years.
  • Said after the Treaty of Versailles, as quoted in Memoires (1963) by Paul Reynaud, vol. 2, p. 457

• None but a coward dares to boast that he has never known fear.
  • As quoted in Encarta Book of Quotations (2000) by Bill Swainson and Anne H. Soukhanov, p. 338

• The will to conquer is the first condition of victory.
  • The Book of Positive Quotations (2007) by John Cook, Steve Deger, and Leslie Ann Gibson, p. 370

Precepts and Judgments (1919)

As translated by Hilaire Belloc (1920) Full text online

• In tactics, action is the governing rule of war.
  • p. 79

• To inform, and, therefore to reconnoitre, this is the first and constant duty of the advanced guard.
  • p. 83

• The laurels of victory are at the point of the enemy bayonets. They must be plucked there; they must be carried by a hand-to-hand fight if one really means to conquer.
  • p. 105

• Against what should fire be opened? Against the obstacles which may delay the march of infantry.
  The first obstacle is the enemy gun. It will be the first objective assigned to artillery masses.
  • p. 108

• There is but one means to extenuate the effects of enemy fire: it is to develop a more violent fire oneself.
  • p. 110

• An army is to a chief what a sword is to a soldier. It is only worth anything in so far as it receives from him a certain impulsion (direction and vigour).
  • p. 138

• When the moment arrives for taking decisions, facing responsibilities, entering upon sacrifices — decisions which ought to be taken before they are imposed, responsibilities which ought to be welcomed, for the initiative must be secured and the offensive launched — where should we find a man equal to these uncertain and dangerous tasks were it not among men of a superior stamp, men eager for responsibilities? He must indeed be a man who, being deeply imbued with a will to conquer, shall derive from that will (as well as from a clear perception of the only means that lead to victory) the strength to make an unwavering use of the most formidable rights, to approach with courage all difficulties and all sacrifices, to risk everything; even honour — for a beaten general is disgraced for ever.
  • p. 140

• The distribution of troops devoted to the defence of a place includes a garrison, an occupying force, numerically as weak as possible; a reserve as strong as possible, designed for counterattacking and for providing itself, at the moment it goes into action, with a security service which will guard it from any possible surprise.
  • p. 147

• 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.
  • p.

• In a time such as ours when people believe they can do without an ideal, cast away what they call abstract ideas, live on realism, rationalism, positivism, reduce everything to knowledge or to the use of more or less ingenious and casual devices — let us acknowledge it here — in such a time there is only one means of avoiding error, crime, disaster, of determining the conduct to be followed on a given occasion — but a safe means it is, and a fruitful one; this is the exclusive devotion to two abstract notions in the field of ethics: duty and discipline; such a devotion, if it is to lead to happy results, further implies besides… knowledge and reasoning.
  • p. 150
  • Variant translation: In our time, which thinks it can do without ideals, that it can reject what it calls abstractions, and nourish itself on realism, rationalism and positivism; which thinks it can reduce all questions to matters of science or to the employing of more or less ingenious expedients; at such a time, I say, there is but one resource if you are to avoid disaster, and only one which will make you certain of what course to hold upon a given day. It is the worship — to the exclusion of all others — of two Ideas in the field of morals: duty and discipline. And that worship further needs, if it is to bear fruit and produce results, knowledge and reason.
    • As quoted in "A Sketch of the Military Career of Marshal Foch" by Major A. Grasset

• In war there are none but particular cases; everything has there an individual nature; nothing ever repeats itself.
  In the first place, the data of a military problem are but seldom certain; they are never final. Everything is in a constant state of change and reshaping.
  • p. 152

• 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 (épures), plans (schémas), etc. One only right solution imposes itself : namely, the application, varying according to circumstances, of fixed principles.
  • p. 154

• The truth is, no study is possible on the battle-field; one does there simply what one can in order to apply what one knows. Therefore, in order to do even a little, one has already to know a great deal and to know it well.
  • p. 175

• Every manoeuvre must be the development of a scheme; it must aim at a goal.
  • p. 175

• Men called to the conduct of troops should prepare themselves to deal with cases more and more varied upon an ever-increasing horizon of experience. They can only be given the capacity to arrive at a prompt and judicious position by developing in them through study their power of analysis and of synthesis; that is, of conclusion in a purely objective sense, conclusion upon problems which have been actually lived and taken from real history. Thus also can they be founded through the conviction that comes from knowledge in a confidence sufficient to enable them to take such decisions upon the field of action.
  • p. 199

• The unknown is the governing condition of war.
  • p. 209

• Far from being a sum of distinct and partial results, victory is the consequence of efforts, some of which are victorious while others appear to be fruitless, which nevertheless all aim at a common goal, all drive at a common result: namely, at a decision, a conclusion which alone can provide victory.
  • p. 209

• A war not only arises, but derives its nature, from the political ideas, the moral sentiments, and the international relations obtaining at the moment when it breaks out.
  This amounts to saying : try and know why and with the help of what you are going to act; then you will find out how to act.
  • p. 211

• 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.
  • p. 214

Disputed

• A radish will never stand in the way of victory.
  • As quoted in M*A*S*H, Season 3, Episode 1, "The General Flipped At Dawn"; this seems to be a humorous misattribution.