One difference that I find that separates the great intellectuals and academics from the mediocre ones is that the good ones will go to great lengths to explain how they came to their conclusions. More than simply saying that things are the way they are and that what one says works and should be taken as fact, the best teachers will explain why it is so. They will take you from simple and widely accepted positions and, through logical and rational discussion, lead you to their conclusion. Even if you disagree with their conclusion, you understand how they came to it because they took you on that intellectual journey. Clausewitz does just that for practically every position he states as the nature of things in war and politics.
Clausewitz has an underlying goal in his writing, and that is to get the audience to understand the nature of warfare and its relationship with diplomacy between nations. He uses analogies to help the reader understand and view a topic from a new perspective. He references historical battles to flesh out a concept with a real-world example. Do note, though, that he is a man of his time, and his references to battles and historical figures can go over our heads as we are 200 years later from his time period. Finding an edition of “On War” with good footnotes from the translator/editor will help us understand these references and provide better clarity.
As he attempts to teach us his perspective on the theory of warfare, he also teaches us his views of what any theory provides for us. For him, there are truths that exist that are unshakable truths that manifest themselves as “laws.” Then there are things that are viewed as generally true, as they are manifested as expected except under certain conditions, and these are “principles” of which there are two. “Objective principles” are generally true for every scenario, and “subjective principles” or “maxims” are generally true under certain scenarios. One such scenario is the state of warfare between nations and the nature of open hostilities between groups of organized people ready to fight. His discussion on the theory of warfare discusses these subjective principles or maxims that are generally true and can therefore be understood and applied. This is the realm of theory, not in the scientific sense but in the pragmatic and practical sense.
Clausewitz states in “Book Two: On the Theory of War, Chapter I: Branches of the Art of War,”
The knowledge and applications of skill in the preparations for War are engaged in the creation, discipline, and maintenance of all military forces; what general names should be given to them we do not enter into, but we see that artillery, fortifications, elementary tactics, as they are called, the whole organization and administration of the various armed forces, and such things are included. But the theory of War itself occupies itself with the use of these prepared means for the object of war. It needs of the first only the results, that is, the knowledge of the principle properties of the means taken in hand for use. This we call ‘The Art of War’ in a limited sense, or ‘Theory of the Conduct of War’, or ‘Theory of the Employment of Armed Forces’, all of them denoting for us the same thing.
The Art of War thus viewed in its limited sense divides itself again into tactics and strategy. The former occupies itself with the form of the separate combat, the latter with its use. Both connect themselves with the circumstances of marches, camps, cantonments only through the combat, and these circumstances are tactical or strategic according as they relate to the form or to the signification of the battle.
Here, Clausewitz tells us that the theory of warfare, this art of war, is generally focused on the means of war - the battle. All things related to the battle, like movement and fortifications, are included as they serve as auxiliary elements to the conduct of the battle itself. We have a theory that helps us understand what we need to do in order to achieve our ends. Theory helps us contextualize what we are witnessing in the environment and how we can effectively shape that environment. To understand how to employ a military force in battle, how to prepare it for battle, and how to shape the environment so that we may gain an advantage in battle has to come from some set of principles, and these principles are what we call theory.
That being said, we have a theory to achieve our ends, and this theory informs us of how we may be able to shape the environment towards that end - the desired results we want. The theory we develop, any theory for any human endeavor, serves as a guide for how to use the means we have to do just that. Clausewitz saw war as a means to achieve the political objective, and within war, a singular means is available - battle.
In “Book One: On the Nature of War, Chapter II: End and Means,” he states:
We have only one means in War - the battle; but this means, by the infinite variety of paths in which it may be applied, leads us into all the different ways which the multiplicity of objects allows of, so that we seem to have gained nothing; but that is not the case, for from this unity of means proceeds a thread which assists the study of the subject, as it runs through the whole web of military activity that holds it together…
The combat is the single activity in War; in the combat the destruction of the enemy opposed to us is the means to the end; it is so even when the combat does not actually take place, because in that case there lies at the root of the decision the supposition at all events that this destruction is to be regarded as beyond doubt. It follows, therefore, that the destruction of the enemy military force is the foundation-stone of all action in War, the great support of all combinations, which rest upon it like the arch on its abutments.
In Clausewitz's time, destroying the enemy’s capacity to resist was the surest way to achieve the desired ends. Be it the removal of a national threat, the annexation of enemy provinces into your own, supporting allied efforts as part of a mutual treaty, etc., all of these ends could be more effectively achieved through the destruction of enemy resistance. Suppose the enemy can resist and has hopes of actually achieving some modicum of success from resistance. In that case, the ends may not be achieved, so by destroying the enemy’s means of resistance - their armed forces - we can achieve our ends from a position of strength that the enemy would not be able to challenge without further harm to their national interests. The theory, therefore, was predominantly based on setting the conditions for the battle.
Theory, however, is only “generally true,” as previously mentioned. It is the subjective principles that apply to warfare, but may be false should conditions change or there be some aspect of the environment not fully understood, some variable not accounted for that makes the principle false. When need to make the theory useful, to make it work for actual operations in the field, as we may not be able to understand every variable at play. We need a way to turn principles into applicable action that provides us success more than failure.
In “Book Two: On the Theory of War, Chapter IV: Methodicism,” he states:
Methodicism is therefore not founded on determined particular premises, but on the average probability of cases one with another; and its ultimate tendency is to set up an average truth, the constant and uniform application of which soon acquired something of the nature of a mechanical appliance, which in the end does that which is right almost unwittingly…
But principles, rules, prescriptions, and methods are conceptions indispensable to a theory of the conduct of War, in so far as that theory leads to positive doctrines; because in doctrines the truth can only crystallize in such forms.
Clausewitz’ process of Methodicism is simply the process of creating methods that have a probabilistically high chance of achieving the desired results. We may not be able to ever fully understand a situation when we need to make a decision or prepare for a future action right now. Still, through a method of proven principles that have been shown to have worked, we can develop a method of decision-making that improves our chances. These methods eventually develop further into practical concepts that can be shared within an organization for everyone to utilize and understand, making the organization better able to get the results they are looking to achieve. This is “doctrine,” the conceptual guidelines that organizations follow to improve the probability of their success. All organizations, be they military, business, sports, or whatnot, utilize doctrine in some capacity, even if they don’t call it by the name “doctrine.”
So, Clausewitz has discussed that theory is there to guide us on the nature of things. We have established ends, and a means to achieve those ends. And we have methods by which we can use those means to shape that end. But what are these ends? We have mentioned that the military's desired end is the destruction of the enemy armed forces, which makes the enemy nation unable to further resist our nation's will. This goes directly into the political objectives of which Clausewitz emphasizes that the military objectives are always subordinate to the political objectives.