71. My first example is taken from the use made of the German maxim '_Kriegsräson geht vor Kriegsmanier_'. This maxim is a very old one, and there was nothing in the law of nations which stood in the way of its unreserved acceptance so long as there was no real _law_ of war, but the conduct of war rested only on a fluctuating number of general _usages_. The meaning of '_manier_' is '_usage_', and '_Kriegsräson geht vor Kriegsmanier_' means that the usages of war can be pushed aside when the reason of war demands it. At the present day, however, the conduct of war is no longer entirely under the control of _usages_, but under the control of _enacted rules of law_ to be found in the 'Regulations respecting the laws of land war', and the application of the old saw to these legal rules can only lead to abuses and erroneous interpretations. What it says is, in short, nothing else than this: If the reason of war demands it, everything is permissible. But since the first Hague Peace Conference that is definitely no longer the case. Article 22 of the 'Regulations respecting the laws of land war' expressly says that belligerents have not an unlimited right of choice of means of injuring the enemy. _Kriegsräson_, therefore, cannot justify everything. Some enacted rules about the conduct of war are, indeed, framed with such latitude as to allow scope for the operation of _Kriegsräson_. But most of them do not leave it any scope, and they may not remain unobserved even if _Kriegsräson_ were to make it desirable. It must be admitted that the general principle of the law of nations, that such acts as are absolutely necessary for self-preservation may be excused even though illegal, is applicable to the law of war also. And, further, in the exercise of justified reprisals, many enacted rules of war can be set aside. But mere _Kriegsräson_ never extends so far as to dispense with enacted rules of war. Nevertheless numerous well-reputed German authors teach the contrary, and even those who perceive the falsity of this doctrine still retain the old saying and identify _Kriegsräson_ with the narrower idea of military necessity. If we are to arrive at clearness, if possible abuses are not to receive in advance the sheltering protection of law, the maxim '_Kriegsräson geht vor Kriegsmanier_' must disappear from the science of international law. It has lost its meaning and has become an empty but dangerous phrase. [Sidenote: The doctrine of Rousseau concerning war.]