Well the patterns of history are based on the patterns from mob behavior (the sum of the psychology of a mass of people), random happenings in nature (Little Ice Age indirectly leading to religious hysteria and revolution) and the the particularities of cultures and controlling elites. There are patterns, but like the science of fluids, I don't think that that history is even close to totally predictable. Chaos mathematics would say that subtle changes can make for amplified and unpredictable results within the patterns of history.
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In varietate concordia - EU motto
For small creatures such as we the vastness is bearable only through love.
- Carl Sagan