in his first seven books, which alone he left in anything like a finished condition.  It was not till he came to write his eighth book On War Plans that he saw the vital importance of the distinction round which he had been hovering.  In that book the distinction is clearly laid down, but the book unhappily was never completed.  With his manuscript, however, he left a “Note” warning us against regarding his earlier books as a full presentation of his developed ideas.  From the note it is also evident that he thought the classification on which he had lighted was of the utmost importance, that he believed it would clear up all the difficulties which he had encountered in his earlier books—­difficulties which he had come to see arose from a too exclusive consideration of the Napoleonic method of conducting war.  “I look upon the first six books,” he wrote in 1827, “as only a mass of material which is still in a manner without form and which has still to be revised again.  In this revision the two kinds of wars will be kept more distinctly in view all through, and thereby all ideas will gain in clearness, in precision, and in exactness of application.”  Evidently he had grown dissatisfied with the theory of Absolute War on which he had started.  His new discovery had convinced him that that theory would not serve as a standard for all natures of wars.  “Shall we,” he asks in his final book, “shall we now rest satisfied with this idea and by it judge of all wars, however much they may differ?"[2] He answers his question in the negative.  “You cannot determine the requirements of all wars from the Napoleonic type.  Keep that type and its absolute method before you to use when you can or when you must, but keep equally before you that there are two main natures of war.”

  [2] Clausewitz, On War, Book viii, chap, ii

In his note written at this time, when the distinction first came to him, he defines these two natures of war as follows:  “First, those in which the object is the overthrow of the enemy, whether it be we aim at his political destruction or merely at disarming him and forcing him to conclude peace on our terms; and secondly, those in which our object is merely to make some conquests on the frontiers of his country, either for the purpose of retaining them permanently or of turning them to account as a matter of exchange in settling terms of peace."[3] It was in his eighth book that he intended, had he lived, to have worked out the comprehensive idea he had conceived.  Of that book he says, “The chief object will be to make good the two points of view above mentioned, by which everything will be simplified and at the same time be given the breath of life.  I hope in this book to iron out many creases in the heads of strategists and statesmen, and at least to show the object of action and the real point to be considered in war."[4]

  [3] Ibid, Preparatory Notice, p. vii.