Let's take vaccination as an example. First, we have to put aside our own reluctance to let our children experience pain and remember that sometimes a small hurt or inconvenience can prevent a bigger one. A broken engagement is difficult, but if it heads off a disastrous marriage it's worth it. Nobody enjoys wearing a bicycle helmet on a hot day, but it's better than smashing one's head against the curb. Similarly, the brief jab of the hypodermic needle can prevent serious diseases including measles, diphtheria, rubella and pertussis, to name a few, not just for our children but for the wider community. This isn't just theoretical: In late 2014 and early 2015 a multi-state measles outbreak started with a single unvaccinated child at Disneyland.