Based on the evidence so far, there's good reason to believe that genes influence everything and exclusively control nothing. Intelligence, in particular, is a field with lots of evidence for heredity but little evidence for the precise impact of any known gene. We're very early in this research. If you start poking around in scholarly debates over IQ and general intelligence, or "g," you start to realize how much the field resembles astronomy or particle physics, with entities and qualities being calculated from complex inferences rather than directly observed. That's not to say inferences and calculations aren't scientific. But we should beware mistaking them for unshakeable facts.
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