How should you punctuate this sentence?
A) Our Mardi Gras kingcake was purple, green and gold.
B) Our Mardi Gras kingcake was purple, green, and gold.
Answer: It depends on the style guide you’re using.
I know, I know. You want answers in black and white! Right and wrong! You had a mean English teacher who told you that it was absolutely incorrect to leave out the comma after green, as in example A. Or maybe you had a mean English teacher who told you that it was absolutely incorrect to include the comma after green, as in example B.
That comma – the one that you might put after green – is variously called the serial comma (because it’s used with items in a series), the Oxford comma (because it’s used in Oxford University Press publications), and the Harvard comma (because it’s used in Harvard University Press publications). The serial comma is required by a slew of style guides, including those published by the Modern Language Association, Council for Science Editors, University of Chicago Press, American Psychological Association, American Medical Association, and the US Government Printing Office.
Use of the serial comma is forbidden, however, in virtually all newspaper writing (arguably to save column space).
Most of us are not writing for newspapers. So there’s a good place to start – you are (probably) permitted to use the serial comma. But should you? What difference does it make?
Here’s an example.
I dedicate this book to my parents, Ayn Rand and God.
Without the serial comma, this sentence is ambiguous. The author may be dedicating this book to three entities: (1) her parents, (2) Ayn Rand, and (3) God. Or the author may be dedicating this book to her parents, who are (1) Ayn Rand and (2) God.
While we may presume that the author is not the offspring of Ayn Rand and God, the moment in which we stumble over the ambiguity – and even laugh at it – is a moment of distraction from the author’s intent. If the goal in writing is clear communication, then our goal in comma use is to reduce ambiguity and make it easy for the reader to understand our message.
Here’s another example.
The subjects of his documentaries included Nelson Mandela, an 800-year-old demigod and a professional ballerina.
As in the example above, it’s possible to read this sentence as (inaccurately) identifying Nelson Mandela as an 800-year-old demigod and professional ballerina.
However, if you add the serial comma, you still haven’t quite solved your communication problem; perhaps the documentary subjects included two entities: (1) Nelson Mandela, who is an an 800-year-old demigod, and (2) a professional ballerina.
To solve the communication problem, you must rephrase the sentence. One possibility: The subjects of his documentaries included a professional ballerina, an 800-year-old demigod, and Nelson Mandela.
The lesson here is this: clarity above rule-following. We love the serial comma at The Ochsner Journal. Punctuation rules can solve a lot of problems. But we must always stay attentive to the best way to communicate our message, and sometimes the best way is simply to rephrase the sentence.