Individual countries defined by a locatable centre of power may collapse, but civilization as a mechanism for human organization has been existing and will continue to until some form of catastrophic destruction, not merely a plague, the loss of wifi, water issues. Here's a working definition I would offer:
Modern civilization is “the centralized control of monetary policy and force through written organized laws and records.” The combination of these two forces that used written language as their form of control and continuity in a centralized place defines the modern nation-state. One of the first such state to meet this definition is Sumer, where clay tables were used to mark tithing, the first form of money, which was written debt issued by the centralized nation-state to pay workers, and where language developed into a systemized form of alphanumeric code recorded on clay tablets using reeds. This construct of written debt and codes allowed for centralized rule of various city-states. This centralized nation-state then formed into what we know today as governments.
Other notable examples that are precursors, which don’t qualify as civilizations under this definition, would be ancient Egypt, which used hieroglyphics, which is not a fully written language of that employs an alphabet. This example though displays an important precursor of civilization though and allows for the final step to occur.
My definition likely won't appease you, but it does also for the tracking of capital (debt/money) and thus the formation of military forces where pay can be disseminated, and debt incurred. Disease and famines exist in animals and are not a sign of civilization.
But during the plague the English closed the universities, which allowed for Newton to be sent home where he pondered the theory of gravity. It was such a brilliant theory that it took Einstein to reconfigure it, increasing its accuracy from 99.9 percent to 99.999 percent, or something like that. In other words, Newton's theory still is good enough as a basis for modern aviation. That sound civilized enough?
