Celia and I were talking in the car the other day about the meaning of Christmas. I was distracted, negotiating the traffic, thinking about what I had to do after I dropped her off. I mentioned the word “family.”

“I thought Thanksgiving was about family. It seems like every holiday is about family,” she said. And of course to me every holiday is about family, but in varying degrees.

What I should have said, what I wish I’d said, is that Christmas is about hope. It celebrates the birth of a baby king. Not a full-grown king but a king-in-making, and as such is more about the potential than the actual. It celebrates our turn back to the sun and days of warmth and light we can only dream of at this time of year.

It is, then, a day to celebrate something often in short supply in government, in families and in daily human lives — a belief in the unseen.