For Eysenck, g was a biological fact with broad social consequences.
The social climate 1960–2000 was hostile to evidence for a biological intelligence.
By 2000 research vindicated his claims on g's heritability and social consequences.
Cadres of critics disdained the new evidence with evolving, ad hoc evasions.
Since 2000, research shows g to be widely distributed across both brain and genome.