In a blog post last month, John McIntyre took the editors of the AP Stylebook to task for some of the bad rules they enforce. One of these was the notion that “two objects must be in motion to collide, that a moving object cannot collide with a stationary object.” That is, according to the AP Stylebook, a car cannot collide with a tree, because the tree is not moving, and it can only collide with another car if that other car is moving. McIntyre notes that this rule is not supported by Fowler’s Modern English Usage or even mentioned in Garner’s Modern American Usage.
Merriam-Webster’s Dictionary of English Usage does have an entry for collide and notes that the rule is a tradition (read “invention”) of American newspaper editors. It’s not even clear where the rule came from or why; there’s nothing in the etymology of the word to suggest that only two objects in motion can collide. It comes from the Latin collidere, meaning “to strike together”, from com- “together” + laedere “to strike”.
The rule is not supported by traditional usage either. Speakers and writers of English have been using collide to refer to bodies that are not both in motion for as long as the word has been in use, which is roughly four hundred years. Nor is the rule an attempt to slow language change or hang on to a fading distinction; it’s an attempt to create a distinction and impose it on everyone who uses the language, or at least journalists.
What I found especially baffling was the discussion that took place on Mr. McIntyre’s Facebook page when he shared the link there. Several people chimed in to defend the rule, with one gentleman saying, “There’s an unnecessary ambiguity when ‘collides’ involves <2 moving objects.” Mr. McIntyre responded, “Only if you imagine one.” And this is key: collide is ambiguous only if you have been taught that it is ambiguous—or in other words, only if you’re a certain kind of journalist.
In that Facebook discussion, I wrote,
So the question is, is this actually a problem that needs to be solved? Are readers constantly left scratching their heads because they see “collided with a tree” and wonder how a tree could have been moving? If nobody has ever found such phrasing confusing, then insisting on different phrasing to avoid potential ambiguity is nothing but a waste of time. It’s a way to ensure that editors have work to do, not a way to ensure that editors are adding benefit for the readers.
The discussion thread petered out after that.
I’m generally skeptical of the usefulness of invented distinctions, but this one seems especially useless. When would it be important to distinguish between a crash involving two moving objects and one involving only one moving object? Wouldn’t it be clear from context anyway? And if it’s not clear from context, how on earth would we expect most readers—who have undoubtedly never heard of this journalistic shibboleth—to pick up on it? Should we avoid using words like crash or struck because they’re ambiguous in the same way—because they don’t tell us whether both objects were moving?
It doesn’t matter how rigorously you follow the rule in your own writing or in the writing you edit; if your readers think that collide is synonymous with crash, then they will assume that your variation between collide and crash is merely stylistic. They’ll have no idea that you’re trying to communicate something else. If it’s important, they’ll probably deduce from context whether both objects were moving, regardless of the word you use.
In other words, if an editor makes a distinction and no reader picks up on it, is it still useful?