Large changes are possible. Looking for leverage points, this:
In 380 CE, the Emperor Theodosius I decreed by the Edict of Thessalonica that Christianity was to be the official religion of the Empire, outlawing others. The change brought rapid results. From the fourth century of the Common Era (CE, formerly cited as AD) onwards a vast amount of the literature and material culture of antiquity was lost, a great deal of it purposefully destroyed.”
Excerpt From The History of Philosophy
A. C. Grayling
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