Why do we celebrate birthdays? The practice is so ingrained, so ubiquitous that we might not stop to consider the purpose.

We celebrate birthdays because we love the person whose birth we remember. We celebrate because of the resulting goods — the joys, the comforts, the laughs — with which we’ve been blessed since that person entered the world and our lives. Finally, we celebrate them because life itself is a good, and remembering individual lives reminds us of its goodness.