About the end of the Chinese civilization technological advantage in the 16th century:
> War had ravaged the lands, laying waste whole cities. Plague had struck, killing millions, men, women and children buried in mass graves...
> (but) the force that put an end to the Chinese arc of progress was deadlier by far than all of these together, yet seemingly intangible as metaphysics. By the 16th century, the fleets had vanished, the proximate cause political; to this day there is no consensus on the underlying factors.
Also:
> The saving grace has always been the outside: when one nation, one civilization, faltered, another picked up the torch and carried on; but with the march of globalization, there may soon be no more outside.
Perhaps the direction the world is going in the last couple of years, with less unity, is not that bad.