Abstract
This article is an explanation of the causes of war. It shows the inadequacy of existing explanations in terms of competition for scarce resources, aggressiveness as a trait inherent in human nature, and struggle for power. It constructs a new explanation that combines the defensible elements of the inadequate explanations and adds to them conflicts between systems of value on which the identity of the warring parties depends as the most important of the causes of war. It concludes that since values are plural and conflicting, conflicts between systems of value are ineliminable. This has the consequence that war is a permanent adversity that is an unavoidable obstacle to the improvement of the human condition