“The predictive power of an anxiety-prone temperament, such as it is, essentially works in just one direction: not by predicting what these children will become but by predicting what they will not. In the longitudinal studies of anxiety, all you can say with confidence is that the high-reactive infants will not grow up to be exuberant, outgoing, bubbly or bold. Still, while a Sylvia Plath almost certainly won’t grow up to be a Bill Clinton, she can either grow up to be anxious and suicidal, or simply a poet. Temperament is important, but life intervenes.”