People I know who have been pregnant, and especially those who have had difficult pregnancies, have found Oster’s book Expecting Better to be a breath of fresh air. But the individualistic approach to personal risk assessment completely falls apart when it comes to contagion, and Oster’s work on Covid has gotten people killed. From a critique published not long after the vaccine rollout:

Part of the reason that COVID-19 has been such a massive crisis in the United States is a focus on technocratic, individual-level, consumer-choice responses at the expense of centrally planned collective action to reduce transmission (i.e., emphasis on individual choices to wear a mask and “maintain social distance,” instead of short but comprehensive shutdowns of non-essential businesses and activities with social support). This hyper-individualistic focus is common in economics, in epidemiology, and in many of the quantitative social sciences whose tools and expertise have been marshaled to respond to the pandemic—the article is just a particularly extreme example.

Analogies and metaphors are indispensable, especially in a time of global public health emergency, for communicating science to laypeople and scientists alike. However, as mathematician Norbert Wiener warned, “the price of metaphor is eternal vigilance.” While the unvaccinated-kid-as-vaccinated-grandparent analogy communicates one essential truth (low risk to most individual children), it omits another, equally essential truth—a high risk of transmission to others.