Q From Sheila Jones, South Africa: Can you tell me what the Oxford comma is? I came across it recently in The Remorseful Day by Colin Dexter. I wonder whether it may refer to the practice of putting a comma after the penultimate item in a list, before the and — for example ‘eggs, bacon, and sausage’ rather than ‘eggs, bacon and sausage’, which is how I would write it.
A You have it exactly right. That form of punctuation is uncommon in British English, as it obviously is in South Africa, but it’s a characteristic part of the house style of the Oxford University Press, hence the name.
I’m suffering from it at the moment: I don’t use it naturally, but have to remember to do so in the text of the book I’m writing for OUP, or my editor (Hi, Elizabeth!) reprimands me with gentle but absolute authority; when you see it in these pieces, as you sometimes do, it’s because I’ve been thoroughly indoctrinated. It’s also called the Harvard comma from the house style of the Harvard University Press, but the more general term is serial comma. It’s common in American English and it is recommended in the Chicago Manual of Style and other US style guides, though American newspapers frequently omit it, supposedly to save space.
The argument for using it is that it reduces the risk of ambiguity. For example, if you were to write “He studied Roman history, international politics and economics” it is not obvious whether international refers only to politics or also to economics. Putting the serial comma in removes that doubt. In practice, an alert writer will spot the potential problem and can often write around it.
Perhaps the best argument for the serial comma is that apocryphal book dedication: “To my parents, Ayn Rand and God”.