Genetic determinism has never been less justified but it is pushing its way back onto the agendaby Angela Saini / December 12, 2018 / Leave a comment
Published in Mid-winter (Jan-Feb) 2019 issue of Prospect Magazine
One idea to have pushed its way back on to the scientific agenda is genetic determinism, the belief that genes determine the greater portion of human behaviour—that what we are and all we can achieve is encoded like a blueprint in our DNA. In psychologist Robert Plomin’s recent book Blueprint: How DNA Makes Us Who We Are, for example, it is possible to see a version of this “hereditarianism,” albeit it in a more caveated and less crude form than is traditional. It is a dangerous strain of thought.
The paradox is that genetics research in the last couple of decades has only affirmed that complex psychological traits, including intelligence, involve thousands of genes and crucially also large environmental components. There has never been less justification for biological determinism.
Indeed, for those at the bottom of the class heap, differences in performance in intelligence tests have been shown to have zeroheritability. In other words, genes may account for next to nothing if a child is raised in an environment that doesn’t meet her basic needs. Thinking otherwise is a pathology with a dark history.
But then it has always been useful for the winners in any society to find an exogenous basis for their success—think, for example, of the divine right of kings; of the racial ideology that underpinned the slave trade; or, of the fatalist thinking in the Victorian hymn “All Things Bright and Beautiful”: “The rich man in his castle / The poor man at his gate / God made them high and lowly / And ordered their estate.”
The notion of heritability as destiny fulfilled the same role, and so was latched on to in the early 20th centur…