(and, still more, of course, Eastern cultures). Genetic shifts might also explain the extraordinary decline which followed the overrunning of the Roman Empire by Goths, Huns and Franks in the fourth and fifth centuries AD, since, however much one may admire aspects of life in what used to be called the Dark Ages, effectively whole ways of thinking and being, whole aspects of the phenomenological world, simply disappeared in the West for nearly a thousand years.
