In the New York Times:

Some years ago, the evolutionist and atheist Richard Dawkins pointed out to me that Sir Isaac Newton, the founder of modern physics and mathematics, and arguably the greatest scientist of all time, was born on Christmas Day, and that therefore Newton’s Birthday could be an alternative, if somewhat nerdy, excuse for a winter holiday.

Think of the merchandise! Newton is said to have discovered the phenomenon of gravity by watching apples fall in an orchard. (His insight came after pondering why they always fall down, rather than upwards or sideways.) Newton’s Birthday cards could feature the great man discovering gravity by watching a Christmas decoration fall from a tree. (This is a little anachronistic — Christmas trees didn’t come to England until later — but I don’t think we should let that get in the way.)

All very jolly — but then, ’tis the season. Yet things are not so simple. It turns out that the date of Newton’s birthday is a little contentious. Newton was born in England on Christmas Day 1642 according to the Julian calendar — the calendar in use in England at the time. But by the 1640s, much of the rest of Europe was using the Gregorian calendar (the one in general use today); according to this calendar, Newton was born on Jan. 4, 1643.

Rather than bickering about whether Dec. 25 or Jan. 4 is the better date to observe Newton’s Birthday, I think we should embrace the discrepancy and have an extended festival. After all, the festival of Christmas properly continues for a further 12 days, until the feast of the Epiphany on Jan. 6. So the festival of Newton could begin on Christmas Day and then continue for an extra 10 days, representing the interval between the calendars.

A splendid idea, I can see no reasonable objection to taking off December 25 through January 6. In terms of gross domestic product, it’s what happens anyway.

While on the subject: Isaac Newton was born severely premature, so small that he fit into a quart mug. He was not expected to live.

If you’re aware of any holidays other than Newtonmas being celebrated today, please, go and enjoy them.