If Buonaparte, in his invasion of Russia in 1812, concentrated his Army in great masses upon one single road in a manner never heard of before, and thus caused privations equally unparalleled, we must ascribe it to his maxim _that it is impossible to be too strong at the decisive point_. Whether in this instance he did not strain the principle too far is a question which would be out of place here; but it is certain that, if he had made a point of avoiding the distress which was by that means brought about, he had only to advance on a greater breadth of front. Room was not wanted for the purpose in Russia, and in very few cases can it be wanted. Therefore, from this no ground can be deduced to prove that the simultaneous employment of very superior forces must produce greater weakening. But now, supposing that in spite of the general relief afforded by setting apart a portion of the Army, wind and weather and the toils of War had produced a diminution even on the part which as a spare force had been reserved for later use, still we must take a comprehensive general view of the whole, and therefore ask, Will this diminution of force suffice to counterbalance the gain in forces, which we, through our superiority in numbers, may be able to make in more ways than one? But there still remains a most important point to be noticed. In a partial combat, the force required to obtain a great result can be approximately estimated without much difficulty, and, consequently, we can form an idea of what is superfluous. In Strategy this may be said to be impossible, because the strategic result has no such well-defined object and no such circumscribed limits as the tactical. Thus what can be looked upon in tactics as an excess of power, must be regarded in Strategy as a means to give expansion to success, if opportunity offers for it; with the magnitude of the success the gain in force increases at the same time, and in this way the superiority of numbers may soon reach a point which the most careful economy of forces could never have attained. By means of his enormous numerical superiority, Buonaparte was enabled to reach Moscow in 1812, and to take that central capital. Had he by means of this superiority succeeded in completely defeating the Russian Army, he would, in all probability, have concluded a peace in Moscow which in any other way was much less attainable. This example is used to explain the idea, not to prove it, which would require a circumstantial demonstration, for which this is not the place.(*) (*) Compare Book VII., second edition, p. 56. All these reflections bear merely upon the idea of a successive employment of forces, and not upon the conception of a reserve properly so called, which they, no doubt, come in contact with throughout, but which, as we shall see in the following chapter, is connected with some other considerations.