Military Manners and Customs

The preface sets the discussion within the historical period and European civilisation, refusing a firm division between ancient and modern, Christian and Pagan. The argument rejects the belief that increasingly dangerous warfare offers the best hope of ending war, describing a steady increase in suffering as weapons become more effective. The Lateran Council of 1139 is described as condemning the cross-bow for inhumanity and forbidding its use in Christian warfare as destructive of mankind.

Scipio Africanus had some Carthaginian spies brought before him led through his camp and dismissed under escort, accompanied by a polite inquiry about whether they had examined everything to their satisfaction. The consul Lævinus is said to have treated captured spies in the same manner, while Xerxes is described as doing likewise with Greek detectives. The reasoning distinguishes just from unjust war and denies a person's right to participate knowingly and wilfully in a cause that the person believes unjust.