The lecture looks at how war and conflict have influenced the evolution of man.
The need to have a significant armed force first arose as ancient hunter-gatherer societies turned to agriculture. Although earlier humans had also at times been aggressive in defending their territories, it was the quick exhaustion of soil in agricultural societies that pushed tribes to try and conquer new areas and treat whoever occupied the desired land as an obstacle that had to be eliminated. Humans learned to hunt other humans and subject them to genocide, slavery, and exploitation. The war between humans transcended the limits of intraspecific competition: the tools of war were perfected until men gained the ability to destroy all humanity.
“In one point of view, the art of war is a natural art of acquisition, for the art of acquisition includes hunting, an art which we ought to practice against wild beasts, and against men who, though intended by nature to be governed, will not submit; for war of such a kind is naturally just.” Aristotle, Politics