One of G×E research’s important contributions is often overlooked by scientists: teaching the falsehood of genetic (and environmental) determinism (158). For over a century the public has been fed a diet of determinism, beginning with early 20th-century eugenics policies to correct all human flaws by culling the breeding stock. Mid-century opinions swung back toward naive environmental determinism, exemplified by B.F. Skinner’s 1948 Walden Two. In the late 20th century, public opinion was compelled toward genetic determinism again when high heritability estimates were taken to imply that nongenetic factors have little importance for mental health and behavior. Discoveries of single mutations causing rare disorders strengthened the public’s belief that knowing one’s genetic makeup is tantamount to knowing one’s future. Deterministic beliefs, environmental or genetic, are dangerous. Determinism encourages policies that violate human rights (at worst) and waste resources on ill-conceived mental health improvement programs (at best). Media coverage of this century’s new findings of gene-environment interaction (and environmental effects on gene expression) is persuading the public to embrace a more realistic, nuanced understanding of the causes of behavior, in which some
