5 Cases of Excessive Commas

The rules about commas can seem so complicated — and contradictory — that writers can (almost) be forgiven for tossing in an extra one or two. Here are several examples of overly generous deployment of commas.

1. “If a killer asteroid was, indeed, incoming, a spacecraft could, in theory, be launched to nudge the asteroid out of Earth’s way, changing its speed and the point of intersection.”
This thirty-word sentence is littered with six commas — one for every five words — five of them appearing before the halfway point. By simply bending the rule about bracketing interjections with commas — a rule that advocates of open punctuation flout routinely anyway — the number is reduced by two, rendering the sentence more free flowing: “If a killer asteroid was indeed incoming, a spacecraft could, in theory, be launched to nudge the asteroid out of Earth’s way, changing its speed and the point of intersection.”

One more comma can be eliminated by relocating the parenthetical phrase “in theory” to an earlier position in the sentence, so that the comma after incoming does double duty: “If a killer asteroid was indeed incoming, in theory, a spacecraft could be launched to nudge the asteroid out of Earth’s way, changing its speed and the point of intersection.”

2. “The metaphor, ‘The world is a machine,’ began to replace the metaphor, ‘The world is a living organism.’”
In this sentence, the comma preceding each instance of metaphor implies that that metaphor is the only one — not just in the sentence, but anywhere. (But two metaphors are expressed here, and innumerable others exist.) Metaphor, appearing in apposition to the two brief quotations, should not be set off from them: “The metaphor ‘The world is a machine’ began to replace the metaphor ‘The world is a living organism.’”

3. “The event is part of a catchy, public health message about the importance of emergency preparedness.”
Catchy and “public health” are not coordinate adjectives. The point is not that the message is catchy and public health; it’s that the public health message is catchy. Therefore, no comma is necessary: “The event is part of a catchy public health message about the importance of emergency preparedness.”

If, by contrast, the sentence read, for example, “The event is part of a catchy, quirky message about the importance of emergency preparedness,” note that because catchy and quirky are parallel — they are coordinate adjectives — a comma should separate them.

4. “The report was completed in December, 2012.”
A comma is necessary between a month and a year only if a date is specified (“The report was completed on December 1, 2012”): “The report was completed in December 2012.” (The same rule applies when the name of a season appears in place of the name of a month: “The report was completed in fall 2012.”)

5. “Jones traveled by boxcar from California to New York with fellow fledgling artist, John Smith, sketching the American landscape along the way.”
Commas are necessary with this type of apposition only if the epithet is preceded by an article (“Jones traveled by boxcar from California to New York with a fellow fledgling artist, John Smith, sketching the American landscape along the way”): “Jones traveled by boxcar from California to New York with fellow fledgling artist John Smith sketching the American landscape along the way.” Unfortunately, this type of error has gone viral — its ubiquity is mistaken for propriety — and is seemingly ineradicable.