Emily Oster

In a dubious revolution in child-rearing, the superstitions of old wives have been replaced by the superstitions of child-rearing experts. Mothers are now pelted with advice on how they are harming their kids, from sleeping on their backs during the third trimester to praising them with “Good job!” The advisories, no matter how onerous, contradictory, or tenuous, ratchet ever upward, since who wants to take a chance?

A savior for whipsawed mothers is Emily Oster, a professor at Brown—not of pediatrics or psychology but economics. In best-selling books (Expecting Better, Cribsheet, and most recently The Family Firm), her popular newsletter, and social media, Oster weighs trade-offs, distinguishes trivial from substantial risks, and evaluates evidence for causation in a messy world. Enriching this analytical brilliance is the common sense and empathy that come from being a mother herself.

Oster shows how data, a scary word, can be a humanizing force. As one mother put it, “She restored my sense of being an adult with a working brain and not just a working uterus.”

Pinker is the Johnstone Professor of Psychology at Harvard University and the author of The Blank Slate and Rationality

Contact us at letters@time.com.