The essays analyze the psychological and institutional roots of armed conflict, emphasizing that human action arises from both instinctive impulses and deliberate desires. The author argues that unexamined beliefs and social structures channel impulses toward collective violence, so appealing to reason alone is inadequate to prevent war. He surveys how the state, property relations, education, marriage and population policies, and organized religion can either foster or check belligerent tendencies, and outlines practical political, social, and moral reforms intended to cultivate oppositional passions to war and reorganize economic and civic life so that war becomes unattractive and avoidable.