The other day I was talking to someone I love when suddenly, a gulf opened up between my reality and hers. She was, I realized, a vaccine skeptic. Not an active denier, really—just, as she put it, someone who “doesn’t know where the truth is on this.” This is a smart person and careful to avoid misinformation, so I asked why she didn’t recognize what I assumed to be staggeringly obvious—that vaccination is needed to protect not just ourselves, but the most vulnerable people in our community.