There are different factors in different places it"s really hard to generalize. A high proportion of the conflicts are in impoverished countries, which leads me to. Human nature fear, greed, and so forth. suspect that there are big problems with the way the world is organized. Wide range of meanings in common usage. Behaviour manifesting apparent readiness to cause harm or assert dominance: instinctivism. Aggression as an innate drive or survival-enhancing instinct (jeong, p. 65) War is in our genes : rooted in inherited animal instincts: sociobiology & evolutionary psychology. Social behaviour shaped by evolutionary pressures and natural selection . Unconscious forces drive human behavior (jeong, p. 65) Civilization through repression of these instinctive forces & behaviours. Repress aggression at the interpersonal level and it resurfaces at the intergroup level. Critiques of using innate aggression theories to explain war (1 of 2) Underestimate importance of nurture, social structures, potential for transformation.