Unquestionably it would be a mistake to try to discover from the chemical ingredients of a grain of corn the form of the ear of corn which it bears, as we have only to go to the field to see the ears ripe. Investigation and observation, philosophy and experience, must neither despise nor exclude one another; they mutually afford each other the rights of citizenship. Consequently, the propositions of this book, with their arch of inherent necessity, are supported either by experience or by the conception of War itself as external points, so that they are not without abutments.(*) (*) That this is not the case in the works of many military writers especially of those who have aimed at treating of War itself in a scientific manner, is shown in many instances, in which by their reasoning, the pro and contra swallow each other up so effectually that there is no vestige of the tails even which were left in the case of the two lions. It is, perhaps, not impossible to write a systematic theory of War full of spirit and substance, but ours hitherto, have been very much the reverse. To say nothing of their unscientific spirit, in their striving after coherence and completeness of system, they overflow with commonplaces, truisms, and twaddle of every kind. If we want a striking picture of them we have only to read Lichtenberg’s extract from a code of regulations in case of fire. If a house takes fire, we must seek, above all things, to protect the right side of the house standing on the left, and, on the other hand, the left side of the house on the right; for if we, for example, should protect the left side of the house on the left, then the right side of the house lies to the right of the left, and consequently as the fire lies to the right of this side, and of the right side (for we have assumed that the house is situated to the left of the fire), therefore the right side is situated nearer to the fire than the left, and the right side of the house might catch fire if it was not protected before it came to the left, which is protected. Consequently, something might be burnt that is not protected, and that sooner than something else would be burnt, even if it was not protected; consequently we must let alone the latter and protect the former. In order to impress the thing on one’s mind, we have only to note if the house is situated to the right of the fire, then it is the left side, and if the house is to the left it is the right side.