Godwin’s law dictates that all online arguments, if they’ run for long enough, will end up comparing someone to Hitler. But the Nazis are apt to turn up sooner rather than later in arguments about genetics and human behaviour. If the left too often flinches at what the science says, invoking the spectre of eugenics, the hard- right latches on eagerly hoping to confirm its prejudices about race and inequality. Robert Plomin transcends this divide. While he insists that pretty much all of our behaviours are governed to some degree by genetics, his politics are on the liberal left. He wants research to inform progress towards a fairer society Our prospects for health, wealth and happiness, he argues, are substantially influenced by the shake of the dice when sperm meets egg. But, he adds, “genetic wealth is its own reward.” We should, says Plomin, challenge a value system that confers extra rewards on those who got lucky in the genetic lottery.
What exactly do genes imply about our behaviour and abilities? Plomin shows persuasively that the genes we inheri0t affect, sometimes profoundly, our personality, temperament, physical and mental health and, thereby, our life outcomes. But the metaphor invoked in his title, while common enough, is deeply misleading. In an engineer’s blueprint, individual elements map directly, transparently and predictively on to real-world outcomes. But genes don’t do any such thing. And although Plomin tries to dispel accusations of biological determinism by repeating the slogan of today’s geneticists that “genes are not destiny,” I suspect many readers of Blueprint will be left wondering why not.