Chapter 1 examines war’s place in a universal paradigm of order and chaos, balance and imbalance; explores war’s origins and relationship to human nature; and concludes by formally defining war. After relating Aristotle’s “four causes” model (material, formal, efficient, and final) to war as an organizing concept, the chapter articulates war’s alignment within a universal theme of balance and characterizes war as an amalgam of twenty “dialectics,” including order-chaos and creation-destruction. It highlights how political imbalances can spark war and how dialectical disparities undermine war theory and strategy. Next, the chapter marshals multidisciplinary evidence to argue that evolutionary processes have imbued humanity with warlike and peaceful attributes and that war ultimately reflects human choices arising from various motives including Thucydides’s fear, honor, and interest. Finally, the chapter concludes by defining war as the nexus of a new trinity – humanity, politics, and combat – evaluating the boundaries between war and peace, and taking a first look at the question of war’s inevitability as a human activity.