The causes which condition the use of the combat in Strategy may be easily divided into elements of different kinds, such as the moral, physical, mathematical, geographical and statistical elements.
The first class includes all that can be called forth by moral qualities and effects; to the second belong the whole mass of the military force, its organisation, the proportion of the three arms, &. &.; to the third, the angle of the lines of operation, the concentric and eccentric movements in as far as their geometrical nature has any value in the calculation; to the fourth, the influences of country, such as commanding points, hills, rivers, woods, roads, &. &.; lastly, to the fifth, all the means of supply. The separation of these things once for all in the mind does good in giving clearness and helping us to estimate at once, at a higher or lower value, the different classes as we pass onwards. For, in considering them separately, many lose of themselves their borrowed importance; one feels, for instance, quite plainly that the value of a base of operations, even if we look at nothing in it but its relative position to the line of operations, depends much less in that simple form on the geometrical element of the angle which they form with one another, than on the nature of the roads and the country through which they pass.
But to treat upon Strategy according to these elements would be the most unfortunate idea that could be conceived, for these elements are generally manifold, and intimately connected with each other in every single operation of War. We should lose ourselves in the most soulless analysis, and as if in a horrid dream, we should be for ever trying in vain to build up an arch to connect this base of abstractions with facts belonging to the real world. Heaven preserve every theorist from such an undertaking! We shall keep to the world of things in their totality, and not pursue our analysis further than is necessary from time to time to give distinctness to the idea which we wish to impart, and which has come to us, not by a speculative investigation, but through the impression made by the realities of War in their entirety.