Humans are fascinated by the source of their failings and virtues.
This preoccupation inevitably leads to an old debate: whether nature or nurture molds us more.
A revolution in genetics has poised this as a modern political question about the character of our society: if personalities are hard-wired into our genes, what can governments do to help us?
It feels morally questionable, yet claims of genetic selection by intelligence are making headlines.
This is down to "hereditarian" science and a recent paper claimed, "differences in exam performance between pupils attending selective and non-selective schools mirror the genetic differences between them."
With such an assertion, the work was predictably greeted by a lot of absurd claims about "genetics determining academic success."
What the research revealed was the rather less surprising result: the educational benefits of selective schools largely disappear once pupils' inborn ability and socio-economic background were taken into account.
It is a glimpse of the blindingly obvious — and there's nothing to back strongly either a hereditary or environmental argument.
Yet the paper does say children are "unintentionally genetically selected" by the school system.
Central to hereditarian science is a tall claim: that identifiable variations in genetic sequences can predict an individual's aptness to learn, reason and solve problems.