Along the same line, for thousands of years different civilizations rose, prospered, ran out of energy and died leaving only small mostly forgotten remnants of themselves. Now, thanks to the connectedness (ideas and trade) of the world, the civilizations lose their power and influence but do not disappear into the dark ages. It is like a world civilization and when it disappears, it will likely disappear all over.
Everything should be made as simple as possible, but not simpler. - Albert Einstein