He also goes further in this explanation in another work (whose name eludes me), in so far as some races deliberately seed the galaxy with humans so that when a

He also goes further in this explanation in another work (whose name eludes me), in so far as some races deliberately seed the galaxy with humans so that when a race such as ours breaks free of their solar system, they don't get all hegemonic because there are already humans everywhere. This saves many nasty wars.