the Napoleonic wars from this point of view, I assure you that these simple classic movements which we study here, and which you will come and see us practising in the field, just for the pleasure of a walk, you young rascal—no, I know you’re not well, I apologise!—well, in a war, when you feel behind you the vigilance, the judgment, the profound study of the Higher Command, you are as much moved by them as by the simple lamps of a lighthouse, only a material combustion, but an emanation of the spirit, sweeping through space to warn ships of danger. I may have been wrong, perhaps, in speaking to you only of the literature of war. In reality, as the formation of the soil, the direction of wind and light tell us which way a tree will grow, so the conditions in which a campaign is fought, the features of the country through which you march, prescribe, to a certain extent, and limit the number of the plans among which the general has to choose. Which means that along a mountain range, through a system of valleys, over certain plains, it is almost with the inevitability and the tremendous beauty of an avalanche that you can forecast the line of an army on the march.” “Now you deny me that freedom of choice in the commander, that power of divination in the enemy who is trying to discover his plan, which you allowed me a moment ago.” “Not at all. You remember that book of philosophy we read together at Balbec, the richness of the world of possibilities compared with the real world. Very well. It is the same again with the art of strategy. In a given situation there will be four plans that offer themselves, one of which the general has to choose, as a disease may pass through various phases for which the doctor has to watch. And here again the weakness and greatness of the human elements are fresh causes of uncertainty. For of these four plans let us assume that contingent reasons (such as the attainment of minor objects, or time, which may be pressing, or the smallness of his effective strength and shortage of rations) lead the general to prefer the first, which is less perfect, but less costly also to carry out, is more rapid, and has for its terrain a richer country for feeding his troops. He may, after having begun with this plan, which the enemy, uncertain at first, will soon detect, find that success lies beyond his grasp, the difficulties being too great (that is what I call the element of human weakness), abandon it and try the second or third or fourth. But it may equally be that he has tried the first plan (and this is what I call human greatness) merely as a feint to pin down the enemy, so as to surprise him later at a point where he has not been expecting an attack. Thus at Ulm, Mack, who expected the enemy to advance from the west, was surrounded from the north where he thought he was perfectly safe. My example is not a very good one, as a matter of fact. And Ulm is a better type of enveloping battle, which the future