1. The theory of warfare tries to discover how we may gain a preponderance of physical forces and material advantages at the decisive point. As this is not always possible, theory also teaches us to calculate moral factors: the likely mistakes of the enemy, the impression created by a daring action, yes, even our own desperation. None of these things lie outside the realm of the theory and art of war, which is nothing but the result of reasonable reflection on all the possible situations encountered during a war. We should think very frequently of the most dangerous of these situations and familiarize ourselves with it. Only thus shall we reach heroic decisions based on reason, which no critic can ever shake. Any person who may present this matter differently to Your Royal Highness is a pedant, whose views will only be harmful to you. In the decisive moments of your life, in the turmoil of battle, you will some day feel that this view alone can help where help is needed most, and where a dry pedantry of figures will forsake you.
2. Whether counting on physical or moral advantages, we should always try, in time of war, to have the probability of victory on our side. But this is not always possible. Often we must act AGAINST this probability, SHOULD THERE BE NOTHING BETTER TO DO. Were we to despair here, we would abandon the use of reason just when it becomes most necessary, when everything seems to be conspiring against us. Therefore, even when the likelihood of success is against us, we must not think of our undertaking as unreasonable or impossible; for it is always reasonable, if we do not know of anything better to do, and if we make the best use of the few means at our disposal. We must never lack calmness and firmness, which are so hard to preserve in time of war. Without them the most brilliant qualities of mind are wasted. We must therefore familiarize ourselves with the thought of an honorable defeat. We must always nourish this thought within ourselves, and we must get completely used to it. Be convinced, Most Gracious Master, that without this firm resolution no great results can be achieved in the most successful war, let alone in the most unsuccessful. Certainly this thought frequently occupied the mind of Frederick II during his first Silesian wars. Because he was familiar with it he undertook his attack near Leuthen, on that memorable fifth of December, and not because he believed that his oblique formation would very likely beat the Austrians.
3. In any specific action, in any measure we may undertake, we always have the choice between the most audacious and the most careful solution. Some people think that the theory of war always advises the latter. That assumption is false. If the theory does advise anything, it is the nature of war to advise the most decisive, that is, the most audacious. Theory leaves it to the military leader, however, to act according to his own courage, according to his spirit of enterprise, and his self-confidence. Make your choice, therefore, according to this inner force; but never forget that no military leader has ever become great without audacity.