Human history extends for approximately ten thousand years before the Expansion, with written records… — Charles Sheffield

Human history extends for approximately ten thousand years before the Expansion, with written records available for roughly half that time. Unfortunately, the human tendency for self-delusion, self-aggrandizement, and baseless faith in human superiority over all other intelligent life-forms renders much of the written record unreliable. Serious research workers are advised to seek alternative primary data sources concerning humans. —From the Universal Species Catalog (Subclass: Sapients)

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