sentences:  Azar Gat started his career focusing on military history and strategy, exemplified in his 1989 book "The Origins of Military Thought from the Enlightenment to Clausewitz", a book frequently cited especially in relation to Carl von Clausewitz.Over the years he has broadened his scope to include causes, especially the prehistoric causes of war.In conclusion, let us understand more closely the evolutionary calculus that can make the highly dangerous activity of fighting over resources worthwhile.