By studying the data on the intelligence of twins, the team Bouchard reached a controversial conclusion: for people raised in the same culture and the same opportunities, differences in IQ mostly reflect genetic differences, rather than training or education. The researchers estimated the heritability of intelligence is 0.75, indicating the strong influence of heredity. This contradicted the prevailing belief behavioral psychologists, according to which our brain is initially a blank page waiting to be written by the experience. More alarming to some it was that the relationship between intelligence and evoked the harmful legacy theories of eugenics movement of the early twentieth century in England and the United States, which proposed to improve the collective gene pool through selective breeding. Addys Focus [FONT="]& Addys Focus Review[/FONT]