I never said it was, don't patronize me. But it's still a good way to quickly estimate the size of forces by using "army" and "100'000" interchangeably.
Jatte lambastes Calico Rat
Indeed. I wonder how many people ancient economies could concentrate in one place? Cities of a million people wouild take an empire, and thats in a co-operative space. Bringing rowdy groups of men and beasts into a contested space like a battlefield on campaign, I think if you had a million men per side then most would starve to death before or after the battle.
Maybe if they agreed on the battlefield, and heaped the supplies in a "no-go" zone where everyone could refresh themselves between clashes.
Jatte lambastes Calico Rat
Assuming that you could conscript that much of your populace, how would you feed and arm all those guys? This was before canned food and mass production so it don't make sense.