I have just had no less than three reminders

that Christmas is, apparently, fast approaching.
The first reminder came from my dentist yesterday - she told me she did not want to see me until next year and wished me Merry Christmas as I left. Merry Christmas? It's September!
Then I was standing in the post office waiting to send a book off to my godson for his birthday and I heard the post office assistant saying, "Christmas parcel mail for overseas has to be sent by Wednesday". What? It's September!
Then a friend notes that she has found a box of Christmas cards and should write them now and at the same time another one notes that Christmas things have already appeared in the aisles of the supermarket. Christmas cards? It's September!
All this is too soon for me. I do not want to think about Christmas until December at the very least.
My mother was the person who wrote the Christmas cards in our house. She would send letters to people, handwritten letters tucked inside cards from our charity of choice. It took her hours but she was always happy to write letters. I have no idea what she said. Most of them were sent to people she had not seen for years and only corresponded with once a year. They responded in kind although the list grew shorter each year as people died or simply stopped writing cards.
After my mother died my father said that he would send cards to people who sent cards to us. Unlike my mother my father detests writing letters. We still hear from some people my mother wrote to but the list is small. My father dutifully writes some cards and sends them to people he does not see but, like the people he sees on a regular basis, he no longer writes local Christmas cards.
Most of my friends live elsewhere in the world. Not all of them celebrate Christmas. Some of them are Jewish, Muslim and Buddhist, others have no religious beliefs at all. I keep in touch with most by e-mail - on a regular or irregular basis. I exchange cards with some and small gifts with a few.
But I wonder about the actual celebration of Christmas. Most people I know do not attend church, even those who would put down their religion as "Christian" or "Catholic" or "Anglican" on a census form. Some of my friends would say they have no religious beliefs at all. They still celebrate Christmas.
So, what is Christmas? Why do we celebrate Christmas? Do I need to start writing Christmas cards?
I wonder if the newsagent has any of those overseas calendars? I need to get them into the post before next Wednesday.